Answers to after-school exercises from the perspective of human-computer interaction software engineering

In daily life, there are some software products with better interactive performance and some software products with poor interactive performance. Here are some examples:

Software products with better interactive performance:

Google Chrome: Chrome offers a clean and intuitive user interface with fast responsiveness and a smooth browsing experience.

WhatsApp: The interface design of WhatsApp is simple and clear, providing an intuitive chat interface and convenient messaging functions.

Spotify Music Player: Spotify provides a friendly user interface and intelligent recommendation function, allowing users to easily search and play their favorite music.

Microsoft Office suite: Office applications (such as Word, Excel, PowerPoint, etc.) provide a consistent user interface and easy-to-use functions, enabling users to efficiently handle office tasks.

Software products with poor interactive performance:

Some TV remotes from specific manufacturers: Some TV remotes have confusing button layouts and obscure function names, causing confusion for users.

The shopping process of some e-commerce websites: the shopping process design of some websites is complicated, and the navigation is not clear, causing troubles in the shopping experience for users.

The login interface of some mobile applications: The login interface design of some applications is not friendly enough, and there may be problems such as difficult identification of verification codes and complicated password reset procedures, which bring inconvenience to users.

Privacy settings of some social media platforms: The privacy settings of some social media platforms are relatively complicated, and it is difficult for users to understand and configure their own privacy options correctly, which may lead to the risk of information leakage.

For the listed products, the design quality can be evaluated from the following aspects:

Aspects of well-designed places:

Clear and concise interface: A good design should have a clear and concise user interface, avoiding excessive visual clutter and functional redundancy.

User feedback and guidance: A good design will provide clear user feedback, such as indicator bars, error prompts, etc., to help users understand the results of the current operation and how to proceed next.

Consistency and predictability: Users expect a consistent design style and interaction patterns across different interfaces and functions, which reduces learning costs and increases efficiency.

Response speed and performance: A good design should provide fast response speed and smooth operation experience, so as to avoid long waiting time for users or freezing operation.

Poor design aspects and suggestions for improvement:

Complicated operation process: If the operation process of a certain software is too complicated, you can consider simplifying the process, optimizing navigation and providing clearer guidance to reduce user confusion.

Privacy settings are unclear: For applications involving personal privacy such as social media, a clear privacy setting interface should be designed to provide easy-to-understand and configure options, while strengthening user education so that users can understand and master privacy protection methods.

Unclear function labels or icons: Intuitive function labels and icons should be designed to avoid using obscure words or unclear icons to improve users' understanding and recognition of functions.

Lack of user customization options: user customization is an important part, and the software should provide some customization options, allowing users to adjust the interface layout, function settings, etc. according to their preferences and needs.

Improvement suggestions should be optimized based on specific products and user groups, combined with user research and feedback. At the same time, user testing and iterations are constantly performed to ensure the effectiveness of design improvements.

Introduction to the Executive/Evaluation Activity Cycle EEC

Execution/Evaluation Cycle (EEC) is a cyclic process used to guide execution and evaluation activities in software engineering. The cycle is applied at different stages of software development to ensure that the project is on schedule, meets the expected quality standards, and provides feedback and guidance for further improvement.

The execution/evaluation activity cycle typically includes the following main phases:

Execution phase: In this phase, the actual development work of the software project is performed. This includes activities such as requirements analysis, design, coding, testing and integration. The goal of the execution phase is to effectively implement the software system in accordance with the project plan and design requirements.

Evaluation (Evaluation) phase: In this phase, the execution results of the software project are evaluated and analyzed. Evaluation can include many aspects, such as functional testing, performance testing, user experience evaluation, etc. The goal of the evaluation phase is to determine the quality level of the software system, discover problems and potential risks, and provide feedback and decision-making basis for improvement.

Feedback and Improvement phase: According to the evaluation results, give feedback and improvement to the software system. This might involve fixing discovered issues, optimizing performance, improving the user interface, and more. The goal of the Feedback and Improvement phase is to improve the quality and performance of the software system to meet user needs and project goals.

The execution/evaluation activity cycle is a cyclic process, which means that after a round of execution and evaluation is completed, necessary adjustments and improvements can be made based on the evaluation results, and execution and evaluation can be performed again. This cyclic and iterative approach helps to continuously optimize the software development process and results, and gradually improve the quality and reliability of the software system.

Through the Execute/Evaluate activity cycle, software development teams are able to continuously learn and improve, ensuring that projects are delivered on time and meet user needs and expectations. This cycle emphasizes the importance of continuous execution and evaluation in software development to achieve high-quality software products and project success.

Chapter two

Why is the 7±2 theory not suitable for the design of menus and toolbars?

The 7±2 theory, also known as the short-term memory capacity theory, is an idea developed by psychologist George Miller. The theory holds that human beings have limited short-term memory capacity and can process about 7 information units at the same time, ranging from 5 to 9. However, in the design of menus and toolbars, the 7±2 theory does not apply for the following reasons:

Variety of options: Menus and toolbars often contain a variety of options, such as different menu items, function buttons, and tool icons. These options may refer to various operations, functions and features. Therefore, only limited to about 7 options may not be able to meet the complex application requirements, limiting the user's operation options and function usage.

Hierarchical structure and grouping: In order to provide more functions and options, menus and toolbars are often hierarchical and grouped. In this way, options can be grouped, categorized, and organized for better understanding and access to functionality by users. However, hierarchies and grouping add complexity to menus and toolbars beyond the simple 7 or so.

Learning and memory: The design of menus and toolbars needs to consider the user's learning and memory burden. When the number of options exceeds about 7, users need more cognitive effort to learn and remember the location, function and purpose of each option. Too many options can lead to user confusion, hesitation, and wrong operations, reducing user efficiency and satisfaction.

Customizability and personalization: Modern user interface design is increasingly focused on user personalization and customizability. Users expect to be able to adjust menu and toolbar settings to suit their preferences and workflow. Limiting to 7 or so options limits the user's personalization options and ability to customize.

Based on the above reasons, the design of menus and toolbars should flexibly adapt to actual application needs, rather than relying solely on the 7±2 theory. Designers should provide clear, concise and easy-to-navigate menus and toolbars through reasonable information architecture, grouping and filtering mechanisms to meet user needs and improve user experience.

Forgetting is human nature. After understanding this, let’s talk about the interaction design methods that can be used to avoid forgetting events.

Indeed, forgetting is the norm of human memory. In order to avoid the adverse effects of forgetting events in interaction design, the following interaction design methods can be used:

Clear Information Presentation: Make sure information is presented to users in a clear, concise and understandable manner. Use concise language, clear icons and visual elements to help users quickly understand and remember information.

Prominent visual cues: Use visual elements to grab users' attention and remind them of important information. Use visual effects such as color, contrast, and animation to highlight key information and reduce the possibility of users ignoring or forgetting it.

Meaningful organizational structure: Reasonably organize and categorize information, and use clear labels and navigation structures to help users find what they need easily. Use hierarchies, tabs, and menus to enable users to quickly locate and recall needed information.

Provide feedback and confirmation: Inform users of the results and status of their actions through timely feedback mechanisms. Confirm the requirements for important operations, such as deleting data, submitting forms, etc., to reduce adverse consequences caused by users' forgetting or misoperation.

Appropriate reminders and hints: Before key links or important tasks, provide appropriate reminders and hints to help users recall relevant information or operation steps. For example, use notifications, pop-up windows, prompt text, etc. to guide users to complete tasks or remind important information.

Documentation and help resources: Provide easy-to-access documentation, help centers, or help tools where users can consult and obtain relevant information at any time. This can help users quickly find the help and guidance they need when they forget or need to learn more.

User education and training: provide users with education and training resources to help them understand and master the functions and operating procedures of the system. Through training, video tutorials, wizards, etc., increase users' familiarity with the system and reduce the occurrence of forgetting events.

To sum up, through clear presentation of information, visual cues, meaningful organizational structure, feedback and confirmation, reminders and prompts, documentation and help resources, and user education and training, it is possible to effectively avoid forgetting events in interaction design. problems, and improve user experience and efficiency.

third chapter

List several ways to help users reduce the amount of content they need to memorize.

Here are a few ways to help users reduce what they need to remember:

Explicit Markup and Labels: Use clear, unambiguous labels and markers to describe features and options. Make sure labels and markings convey their meaning exactly so users don't need to memorize unnecessary information. For example, use descriptive button labels instead of vague or abstract words.

Icon and Image Assist: Utilize icons and images to represent functions and options. Icons can provide an intuitive visual representation, reducing users' reliance on textual descriptions. Choose icons that are common, understandable, and functionally relevant to help users quickly identify and recall desired actions.

Context-sensitive information: Provide relevant information and tips based on the user's current operation and context. Link relevant information directly to the user's current interface or task, reducing the amount of information users need to recall. For example, provide relevant help text or how-to instructions above a specific action step.

Appropriate Defaults: Set sensible default options based on user expectations and common preferences. Reduce the amount of active setup and memorization required for users by providing default settings that suit the needs of most users. However, make sure that users can easily modify the default settings to suit their individual needs.

Context menu and shortcut menu: Provide options and functions related to the user's current operation through the right-click menu or context menu. This way the user does not need to memorize and look for the location of a particular function, it can be accessed directly from the context menu when needed.

History and recent use: Tracks a user's history and recently used items, allowing users to easily recall and access recent actions or visits. Provide a history list, recent items, or search history so users can quickly find previous content or actions.

Smart Suggest and Auto-Complete: Use Smart Suggest and Auto-Complete to provide possible options and suggestions based on user input or context. This reduces the amount of information the user needs to fully memorize and enter, and provides the possibility of quick selection.

By applying these methods, designers can help users reduce the amount of information that needs to be memorized, improving product usability and user experience. However, care needs to be taken to balance the user's freedom of choice and the need for personalization, as well as provide enough hints and guidance to ensure that users can easily find the information they need when they need it.

4. Give the following core usability goals and user experience goals for interactive software:

a) Mobile devices used to facilitate communication and cooperation among children.

b) Internet applications that help the public access their medical records.

c) Computer Aided Design (CAD) systems used by architects and engineers.

a) Based on mobile devices that facilitate communication and cooperation among children.

Core usability goals:

Ease of use: Ensure that mobile device interfaces and functions are child-friendly and easy to understand and operate.

Adaptable: Offers personalization and adjustment options to meet the needs of children of different ages and abilities.

Security: Keep children safe online while using their devices, preventing unauthorized access and inappropriate content.

UX Goals:

Fun and Creativity: Stimulate children's creativity and interest by providing fun, interactive and motivating features.

Collaborative and Social: Encourages cooperation and social interaction among children, providing sharing and synergistic features.

Education and Learning: Provide educational content and learning opportunities for children, and promote children's learning and development through play and interaction.

b) Internet applications that help the public access their medical records.

Core usability goals:

User-friendliness: The design interface is clean and intuitive, allowing public users to easily access and understand their medical records.

Data Security and Privacy: Ensure users' medical records are properly protected from unauthorized access and data leakage.

Reliability: Provide stable and reliable services to ensure that users can access their medical records at any time.

UX Goals:

Convenience and speed: Enable public users to easily access and manage their medical records, avoiding lengthy processes and waiting times.

Transparent and understandable: Provide clear information and explanations to help users understand the meaning and outcomes of their medical records.

Self-management and participation: Encourage public users to actively participate in their own health management and provide personalized advice and tools.

c) Computer-aided design (CAD) systems used by architects and engineers.

Core usability goals:

Functional integrity: Provide rich functions and tools to meet the needs of architects and engineers for design and drawing.

Flexibility and customization: Allow users to customize the interface and tools according to their own workflow and preferences.

Efficiency and accuracy: optimize the design workflow, provide quick operation and precise measurement tools, and improve work efficiency and design accuracy.

UX Goals:

User-oriented: user-centered design, understanding users' needs and working styles, and providing working environments and tools that meet their expectations.

Visualization and Interactivity: Enhance the user's visual and operational experience through an intuitive graphical interface, real-time preview and interactive feedback.

Collaboration and Teamwork: Supports teamwork, provides sharing and version control features, and facilitates collaboration and communication between architects and engineers.

The above usability goals and UX goals are aimed at providing a better user experience, reducing the cognitive load on users, increasing productivity, and ensuring that users can easily accomplish their tasks and goals.

Design an experiment to measure the usability of icon designs of two different mobile phone software.

To design an experiment to measure the usability of the icon design of two different mobile phone software, you can follow the steps below:

Choose two mobile apps: Choose two mobile apps with similar functions and make sure that they have obvious differences in icon design.

Define usability indicators: Determine the indicators used to evaluate the usability of icon design, such as recognizability (whether the icon can be recognized accurately), recognition time (users can quickly recognize the icon), consistency (consistency between the icon and related functions or content), etc. .

Design experimental tasks: Design a series of tasks related to software functions, requiring participants to use two software to operate. These tasks can include finding specific functions, performing specific actions, etc., ensuring that different icon usage scenarios are covered.

Prepare participants: Recruit a group of participants and make sure they have basic mobile phone experience. Participants were asked to sign an informed consent form, explaining the purpose and process of the experiment.

Conduct the experiment: Divide the participants into two groups, each using one of the software. In order to reduce the learning effect, a crossover design can be adopted, that is, two groups of participants use different software sequences alternately. Participants will perform tasks one by one according to the task list.

Collect data: Record participant performance data, including task completion times, error rates, and evaluation data related to icon design. Data can be collected using observations, questionnaires, recording screen operations, etc.

Analyze and compare the results: Statistically analyze the data and compare the performance differences of the two software in terms of usability indicators. This can include mean comparisons, error rate comparisons, significance tests, etc.

Draw conclusions: According to the data analysis results, evaluate the icon design usability of the two software, and draw conclusions. Indicate which software performs better in terms of usability and explain the reasons for the differences.

Suggestions for improvement: According to the experimental results, suggestions for improving the icon design of software with poor performance are proposed. This can include suggestions for enhanced legibility, improved consistency, improved icon visuals, and more.

Please note that in order to improve the reliability and validity of the experiment, the influence of other factors, such as interface layout, function arrangement, etc., should be controlled as much as possible. Furthermore, the number of participants should be large enough to ensure representativeness of the results. Finally, one could consider combining experimental results with subjective feedback from participants for a more comprehensive assessment.

For user testing, it is more appropriate to select the number of users, and briefly explain the reasons.

In user testing, the number of users selected needs to be weighed according to the specific situation and available resources. While there is no fixed standard number that will work in all situations, in general, a number of participants between 5 and 15 is a more common and appropriate choice.

Here are the reasons for picking a smaller number of users:

Effectiveness: A relatively small number of users may be sufficient to discover most problems and improvements in the system. According to Nielsen's heuristic evaluation rules, testing 5 users can reveal about 80% of the problems.

Resource constraints: Conducting user testing can require a considerable investment of resources, including time, human, and financial resources. Selecting a smaller number of users enables testing with limited resources, and it is also easier to manage and analyze data.

Time Efficiency: A smaller number of users helps to complete the test in less time. This is beneficial for projects with tight time constraints or for iterative testing in agile development processes.

However, the following factors also need to be considered:

Diversity: Try to select users with different backgrounds, experiences and skills to ensure the diversity and representativeness of test results. This allows for a more comprehensive understanding of the needs and feedback of the user community.

Specific goals: If testing is required for a specific group of users or for a specific task, more participants may be required to obtain more reliable results.

In summary, choosing the right number of users should take into account project requirements, available resources, and time constraints. Smaller numbers of users can provide valuable feedback and suggestions for improvement, but care needs to be taken to ensure that testing is diverse and representative. If budget and time permit, more user participation can increase the reliability and generality of the results.

introduce the scene

Scenarios refer to user behavior and interaction situations that occur in a specific environment. In the field of user experience design and human-computer interaction, scenarios describe the specific situations, tasks, and goals of users using a product or service.

Scenario descriptions can include the following:

User roles and characteristics: Describe the user's identity, role and characteristics, such as age, gender, educational background, occupation, etc. This helps designers better understand user needs and context.

Environment and context: Describe the physical environment and context in which the user uses the product or service, such as home, office, outdoors, etc. Environmental factors can influence user behavior and needs.

User goals and tasks: Describe the specific goals and tasks of the user in the scene, such as finding information, performing operations, completing interactions, etc. This helps designers understand the needs and expectations of users in a given situation.

Behavior and interaction process: Describe the user's behavior and interaction process in the scene, such as using specific functions, performing specific steps, interacting with the system, etc. This helps designers analyze user experience and interaction flow.

Scenarios include:

Understand user needs: By describing specific scenarios, designers can gain a deeper understanding of user needs, expectations, and pain points, so as to better meet user needs.

Design user experience: Scenario description can help designers think from the perspective of users and design products or services that better meet user expectations and usage scenarios.

Validate design decisions: Designers can use scenarios to validate and evaluate the effect and usability of design decisions, ensuring that the product meets user needs and goals in actual use.

Communication and collaboration: Scenario descriptions can serve as a communication tool between designers and teams, stakeholders and developers, ensuring a common understanding of user needs and product functionality.

To sum up, scene description is an important tool in user experience design, which is used to describe users' needs, goals and behaviors in a specific situation, so as to help designers better meet users' needs and provide good user experience.

Chapter Four

List two familiar life cycle models, see if they are suitable for developing interactive software systems, and briefly explain why.

The following is a brief description of the applicability of two familiar lifecycle models, waterfall and agile, to developing interactive software systems:

Waterfall model:

Waterfall model is a linear sequential software development model, including requirements analysis, design, coding, testing and maintenance phases. Each stage has clear inputs and outputs, and the next stage cannot be entered until the previous stage is completed.

Applicability: The waterfall model has relatively low applicability in developing interactive software systems. The requirements and design of interactive software systems are usually dynamic and changing, while the waterfall model is relatively rigid and not suitable for frequent changes in requirements. If a major change is required at a later stage, it may be necessary to go back to the previous stage, increasing the risk of time and cost.

Agile model:

Agile model is an iterative and incremental software development model that emphasizes rapid response to changes, continuous delivery and teamwork. Agile development breaks down the development process into short-term iterative cycles called "sprints". Each sprint completes a part of the function and iterates and improves it based on feedback.

Applicability: Agile models are more applicable in developing interactive software systems. The requirements of an interactive software system often change and evolve during the development process, while the iterative and incremental approach of the Agile model enables flexible responses to changes in requirements and improvements through frequent user feedback loops. Agile development also focuses on team collaboration and user participation, which helps to better meet user needs and provide a good user experience.

To sum up, the waterfall model is less suitable for developing interactive software systems, while the agile model is more suitable for such projects. The agile model can better respond to requirements changes and fast delivery requirements, and improve user experience and system quality through iteration and user participation. However, which model to choose should be comprehensively considered according to the characteristics of the project, the ability of the team, and resource constraints.

chapter Five

Write a scenario that shows how to schedule a meeting for multiple people.

Scenario: Multi-person conference arrangement

Role:

Moderator (Alice): responsible for organizing and hosting the meeting.

Participant 1 (Bob): The member who specifically participated in the meeting.

Participant 2 (Charlie): The member who specifically participated in the meeting.

background:

Alice is a project manager and needs to organize a meeting to discuss project progress and next steps. Bob and Charlie are members of the project team and they need to attend this meeting and provide their opinions and suggestions.

Scenario description:

Alice is about to schedule a meeting, and she decides to email Bob and Charlie a meeting invitation.

Alice opens her email client and creates a new email. She writes the subject of the email as "Project Meeting Discussion" and provides the time, date, and location of the meeting in the body of the email.

Alice clearly stated the topic and goal of the meeting in the email, and listed the preparation materials required for the meeting, such as reports, documents or data.

Alice chooses a suitable time slot and uses a scheduling tool (such as a calendar application) to see the available times for herself and Bob and Charlie.

Alice provides several alternative time slots in the email, and requests Bob and Charlie to choose a time they can attend in the reply email.

Alice sends an email invitation to Bob and Charlie, and sets a response deadline so they can reply as soon as possible to confirm their availability.

After Bob and Charlie receive the meeting invitation email, they open the email to check the meeting details. They check their schedules and determine their availability.

Bob replies to the email, selects the time he can attend in the reply, and attaches a confirmation reply.

Charlie also replied to the email, and in the reply, he chose the time when he could participate, and attached a confirmation reply.

Alice confirms the final meeting time after receiving confirmation replies from Bob and Charlie.

Alice sends a meeting update email to Bob and Charlie, providing the final confirmed meeting time, and re-emphasizing the meeting topic and preparation materials.

On the day before the meeting, Alice sends reminder emails to Bob and Charlie again, reminding them of the time and place of the meeting, and attaching the meeting agenda and preparation materials again.

On the day of the meeting, Bob and Charlie arrive at the meeting place at the appointed time, participate in the discussion and provide their own opinions and suggestions.

Through the above scenarios, the arrangement of multi-person meetings can be carried out through email and scheduling tools. The moderator provides the time, topic and preparation materials of the meeting in the email, and requests the participants to choose an available time to attend. Once attendees receive an invitation, they check their schedule and reply to confirm a time when they are available. After the meeting time is finalized, the host sends an update email with the final confirmed time of the meeting and other important information. By being reminded and prepared in advance, meeting participants can arrive on time and participate in discussions.

Write a scenario that shows how to arrange a meeting for multiple people, limited to an online meeting of a college class, and the meeting is organized by the class leader

Scenario: University class online meeting arrangement (organized by the monitor)

Role:

Monitor (Bob): Responsible for organizing and chairing the meeting.

Class Students: The student members in the class.

background:

Bob is the monitor of a college class. He is responsible for organizing an online meeting to discuss class affairs and topics of concern to students.

Scenario description:

Bob decides to use a popular online conferencing platform to schedule a class meeting. He opens the meeting platform's webpage and chooses to create a new meeting.

Bob enters the meeting subject, date and time in the meeting settings. He chooses an evening time slot to make sure most students are free.

Bob provides the purpose and agenda of the meeting in the meeting invitation, including class business, academic discussions, or other activities.

Bob informs the class students that an online meeting is about to be held through the class group or communication channels (such as the class social platform or instant messaging application), and provides the meeting time and the link of the meeting platform.

After students receive the notification, they review the meeting details and confirm their availability. They can confirm whether they can attend before the meeting, and prepare relevant materials or ask questions in advance.

The day before the meeting, Bob sends another reminder notice to the class, reiterating the time, link, and agenda for the meeting. He encourages students to prepare well before the meeting and present their opinions or issues.

On the day of the meeting, students log in to the meeting platform according to the agreed time and enter the online meeting room. They communicate and discuss with monitors and other students through audio, video and chat tools.

Bob acts as the monitor, chairing the meeting and leading the discussion. He ensures that every student has a chance to speak and encourages everyone to share their views and suggestions.

After the meeting, Bob summarizes the main points of the discussion and reminds the students of the next course of action. He can send meeting minutes by email or online platform for students to review and review the discussion.

Through the above scenarios, the class leader is responsible for organizing and hosting the online meeting, and communicates with the help of the online meeting platform and class communication tools. The monitor ensures that students are aware of the meeting schedule and agenda through announcements and reminders, and encourages them to prepare well for the meeting. The students attend the meeting according to the agreed time, and interact and discuss with the monitor and classmates through audio, video and chat tools. Such online meeting arrangement helps to promote cooperation and communication in the class, so that every student's voice is heard and recorded.

Introduce Hierarchical Task Analysis (HTA) and talk about its English full name

Hierarchical Task Analysis (HTA) is a method for analyzing and describing the process of human task execution. It forms a hierarchy by breaking down complex tasks into smaller subtasks to better understand the components and execution flow of tasks.

HTA aims to gain insight into the user's behavior and decision-making process in a specific task, and provides detailed task execution steps and the relationship between subtasks. It can help designers understand users' needs and behaviors, so as to better design and optimize the interface and functions of interactive systems.

The analysis process of HTA usually includes the following steps:

Identify and define the tasks to be analyzed. Determine the scope and objectives of the task.

Break down tasks into subtasks. Break tasks down into smaller, manageable subtasks, forming a hierarchy.

Identify relationships between subtasks. Determine dependencies and order of execution between subtasks.

Describes the execution steps of a subtask. A detailed step-by-step description is given for each subtask, including input, output, and operating procedures.

Analyze decision points in task execution. Identify the decisions and choices involved in task performance, including information processing and judgment processes.

Evaluate and improve mission execution processes. Based on the results of HTA, the efficiency and effectiveness of the tasks are evaluated and suggestions for improvement are made.

The full English name of HTA is "Hierarchical Task Analysis".

Give a textual and graphical description of a hierarchical task analysis of cleaning a house with a vacuum cleaner.

word description:

The following is a textual description of a hierarchical task analysis of cleaning a room with a vacuum cleaner:

Clean the room

1.1 Preparations

1.1.1 Check the status of the vacuum cleaner (power supply, filter, etc.)

1.1.2 Remove obstacles (furniture, debris, etc.)

1.2 Start vacuuming

1.2.1 Determining the starting position

1.2.2 Mobile vacuum cleaner

1.2.2.1 Linear movement

1.2.2.2 Turning movement

1.2.2.3 Corner treatment

1.2.3 Cover the whole room

1.2.3.1 Forward and backward movement

1.2.3.2 Move left and right

1.2.4 Handling special regions

1.2.4.1 Carpet or Floor Edges

1.2.4.2 Under furniture

1.2.4.3 Near windows

1.3 Finish vacuuming

1.3.1 Switching off the vacuum cleaner

1.3.2 Put away the vacuum cleaner cable

1.3.3 Cleaning the vacuum cleaner (emptying the dust bag, cleaning the filter, etc.)

Graphic description:

Here is a graphical depiction of a hierarchical task analysis for cleaning a room with a vacuum cleaner:

Clean the room

+----------------+

| |

Get ready to start vacuuming

| |

+----------+ +------------+

| | | |

Inspect vacuum cleaner Remove obstructions Determine starting position

status | |

| +---------------+

| | |

| Linear movement Mobile vacuum cleaner

| | |

| Turn movement +-----------+

| | | |

| Corner treatment covers the entire room

| | | |

| | Forward and backward Move left and right

| | | |

| | Handling special regions |

| | | |

| +----+ Carpet/Floor Edge |

| | | UNDER FURNITURE |

| | | near the window |

| Finish vacuuming | |

| | | Turn off the vacuum |

| | | Put away the cable |

| Cleaning the vacuum cleaner | |

| | | Cleaning the vacuum cleaner |

+---+----+---------------+

This graph describes the task hierarchy of cleaning a room with a vacuum cleaner, starting from "clean the room" at the top, and gradually subdivided into subtasks such as preparation, starting vacuuming, and ending vacuuming, and further subdivided into specific operation steps. Each subtask is associated with a parent task, forming a hierarchical structure.

Chapter Six

List inconsiderate examples in familiar software and give suggestions for improvement, taking QQ as an example

QQ is a widely used instant messaging software, the following are some possible inconsiderate examples and suggestions for improvement:

Ad Interference:
- Inconsiderate example: frequently popping up advertisement windows or inserting advertisements in the chat window, disturbing the user's chat experience.
- Suggestions for improvement: Reduce the frequency and intrusiveness of ads, and offer a paid version or an ad-free option to improve the user's chat experience.
Complex UI:
- Inconsiderate example: The interface is overly complex, with too many features and setting options, making it difficult for new users to get started and use.
- Suggestions for improvement: Simplify the user interface, provide an intuitive and easy-to-navigate interface, place commonly used functions and settings in an easy-to-access location, and provide novice guidance and help documents to help new users get started quickly.
Security and Privacy Settings:
- Inconsiderate example: the default setting is not strict enough for user privacy protection, and the risk of personal information exposure is high.
- Suggestions for improvement: The default settings should protect users' privacy and personal information security as much as possible, for example, disable the default disclosure of personal information, provide optional privacy settings, and strengthen account security measures, such as two-factor authentication.
Group chat message reminder:
- Inconsiderate example: When receiving a large number of messages in a group chat, there is no effective message filtering or mute option, causing users to be disturbed by too many messages.
- Suggestions for improvement: Provide group chat message filtering and mute options, allowing users to customize reminders or mute certain groups or certain message types to provide better message management and chat experience.
Data synchronization and multi-device support:
- Inconsiderate example: When using QQ on multiple devices, data synchronization and message status are inconsistent, making it impossible for users to switch between different devices conveniently.
- Improvement suggestions: Provide a stable and fast data synchronization mechanism to ensure that message status, contact list and other data are kept in sync across multiple devices to provide a seamless experience.

The key to improving recommendations is to focus on the needs and experience of users, providing simple, intuitive and personalized features and setting options, while protecting users' privacy and security. Ongoing user research, user testing, and feedback loops are critical to continuously improving software with thoughtfulness.

Chapter VII

Please point out what can be done to eliminate the error dialog to avoid making users feel guilty

Here are some things you can do to eliminate error dialogs and save users from feeling guilty:

Clear and Friendly Error Messages: Make sure that error messages are clear, concise, and inform users in a friendly manner. Avoid false prompts with accusatory or threatening language, and instead provide clear explanations and guidance that help users understand the problem and provide a solution.
Friendly user interface design: When designing the user interface, the chances that users may make mistakes should be minimized and the probability of users making mistakes should be reduced as much as possible. Through intuitive, consistent and easy-to-understand interface design, help users complete operations correctly and reduce the possibility of errors.
Undo and rollback functions: Provide undo and rollback functions, allowing users to correct mistakes and restore to the previous state. This way, the user can correct the error and move on without feeling guilty.
Emphasize system errors: When errors are caused by system problems, they should be clearly distinguished from user errors. Indicate that the problem is not the fault of the user, but rather a system failure or error, by providing a clear error message.
User education and training: Help users understand how to properly operate a software or application by providing clear guidance, training, and help documentation. By educating users, the opportunities for users to make mistakes are reduced, and the accuracy and self-confidence of users are improved.
User Feedback and Continuous Improvement: Users are encouraged to provide feedback, especially on issues related to error dialogs or user experience. Through continuous user feedback and improvement process, timely fix errors and improve user experience, reducing the possibility of users feeling self-blame when facing errors.

In short, friendly error prompts, good user interface design, undo function, clear system error prompts, user education and training, and continuous user feedback and improvement can help eliminate error dialogs and reduce user self-blame. possibility.

What are the problems with the confirmation dialog? How to eliminate the confirmation dialog?

The confirmation dialog has some problems:

Overused: Confirmation dialogs are often misused, appearing in unnecessary places, causing unnecessary distraction and cumbersome operations for users.
Unclear content: Some confirmation dialogs are vague, making it difficult for users to understand specific operation results or risks.
Lack of options: Some confirmation dialogs only provide two fixed options of "OK" and "Cancel", regardless of other choices the user may have.

To eliminate confirmation dialogs or reduce their use, the following actions can be taken:

Reasonable trade-off: Before deciding whether to use confirmation dialogs, developers should carefully weigh their necessity. Use confirmation dialogs only before critical or irreversible operations, and avoid routine or undoable operations.
Clear content: The content of the confirmation dialog box should be clear and concise, and clearly express the result or potential risk of the operation. Users need to know exactly what happens when they confirm or cancel.
Provide options: Provide multiple options in the confirmation dialog to meet different needs and preferences of users. For example, instead of "OK" and "Cancel", options such as "Save and Close" or "Save and Continue Editing" may be provided.
Default selection: If the default option in the confirmation dialog is safe and common enough, it can be set as the default selection to reduce the number of times the user needs to take additional actions.
Context Sensitive: Confirmation dialogs should be closely related to the context of an action to help users better understand its meaning and consequences. Avoid generic, unrelated dialog content.
Undo and rollback: For key operations, provide an undo or rollback function so that users can still correct errors or return to the previous state after confirmation.

By judiciously using confirmation dialogs, providing clear content, diverse options, default selections, context sensitivity, and undo functionality, dialogs can be used less frequently and the user experience improved.

What is the difference between Microsoft's "Tooltip" and Apple's "Balloon Help"? Why did "Tooltip" finally win over users?

Microsoft's "Tooltip" (Tooltip) and Apple's "Balloon Help" (Balloon Help) are two common user interface elements used to provide explanation and help for a specific function or control. The following differences exist between them:

Appearance and Style: Microsoft's "tooltips" usually appear in the form of compact text boxes that provide brief hints and can include icons or indicators. Apple's "Balloon Help" appears in the form of a translucent bubble, which is more eye-catching and vivid, and can contain more text and icons.
How it is triggered: Microsoft's "tooltips" are usually triggered by mouse hovering or clicking on a specific control. Apple's "Balloon Help" can be triggered by hovering, clicking, or holding down a specific keyboard shortcut.
Content and level of detail: "Tooltips" typically provide short, precise hints that explain the function or operation of a particular control. "Balloon help" can provide more detailed help information, including steps, examples or links.

There are a few reasons why Tooltips ended up winning over users:

Clear and concise: Tooltips typically provide brief, precise information without overwhelming the user or overloading them with information. Users can quickly learn the information they need without having to browse through extensive help content.
Quick Response: "Tool Tips" can be displayed immediately when the user mouses over or clicks on the control, providing instant feedback and help. Users can quickly access the information they need without additional clicks or actions.
Consistency and predictability: Since "tooltips" are a common user interface element, users will encounter similar tooltip styles and interactions across applications. This consistency and predictability makes tooltips easier for users to understand and use.
Low intrusiveness: "Tooltips" are displayed closer to the control so that they don't obscure what the user is working on. They typically appear near the edge or bottom of controls without taking up a lot of screen real estate or blocking the user's view.

Overall, Tooltips do an excellent job of providing clarity, responsiveness, consistent predictability, and low intrusiveness that make them user-friendly interface elements.

What is the difference between layout complexity and layout uniformity in evaluating interface complexity? What guiding significance do you think they have in practical applications?

Layout complexity and layout uniformity are two different indicators for evaluating interface complexity. They have the following differences in evaluating and understanding interface complexity:

Layout Complexity: Layout complexity is concerned with the complexity of how elements are arranged and organized in an interface. It deals with the structure, hierarchy, and interrelationships between components of the interface layout. Higher layout complexity means that there are multiple elements, multi-level organizational structure and complex layout methods in the interface.
Layout uniformity: Layout uniformity is concerned with the consistency and unity between the elements in the interface. It involves the degree of consistency in the style, size, spacing, and alignment of interface elements. A higher degree of layout uniformity means that the elements in the interface are more visually consistent, forming an overall unified style.

In practical applications, both layout complexity and layout uniformity have important guiding significance:

Design Decisions: Layout complexity and layout uniformity can guide designers in making decisions in interface design. According to factors such as target users, functional requirements, and usage scenarios, balance layout complexity and layout uniformity to achieve ease of use and comprehensibility of the interface.
User experience: Layout complexity and layout uniformity directly affect user perception and experience. Lower layout complexity and higher layout uniformity help provide a clean, clear, and easy-to-navigate interface that increases user satisfaction and efficiency.
Maintainability and consistency: When maintaining and updating the interface for a long time, considering layout complexity and layout uniformity can simplify the workload of development and maintenance. Lower layout complexity and higher layout uniformity make the interface easier to understand, modify, and expand, and easier to maintain consistency.

To sum up, layout complexity and layout uniformity have guiding significance in practical applications, which can help designers balance the complexity and consistency of the interface, provide a good user experience, and simplify the maintenance and update of the interface.

chapter eight

A brief description of Fitts' law and its implications for designers of interactive software systems

Briefly, Fitts' law is an empirical law in the field of human-computer interaction, which describes the relationship between the time for people to perform goal-oriented precise finger movements and the difficulty of the task. This law was proposed by Paul Fitts in 1954 and can be expressed by the following formula:

MT = a + b * log2(D/W + 1)

Among them, MT is the movement time, a and b are constants obtained from experiments, D is the distance from the starting point to the target point, and W is the width of the target.

Jane Fitts' Law has important implications for designers of interactive software systems, as follows:

Design clickable targets: According to Fitts' law, the width of the target has a direct impact on the movement time. Designers can reduce click errors and improve user operation efficiency by increasing the width of the target. A reasonable target size can reduce the user's accuracy requirements and improve the user's click accuracy.
Optimize interface layout: According to Fitts' law, the size of the target distance will also affect the movement time. Designers can optimize the layout of the interface, placing the most frequently used functions or objects of the user at a shorter distance, reducing the user's movement time and effort.
Provide Feedback and Guidance: Fitts' Law emphasizes the relationship between timing and difficulty of precise finger movements. Designers can take advantage of this law to provide users with instant feedback and guidance to help users complete operations more accurately and avoid misoperations and mistakes.
Evaluate and optimize interaction performance: Fitts' law provides an objective way to evaluate and compare the performance of different interaction designs. By measuring the movement time and distance, different interface designs can be compared to find a design with better performance, and further optimization and improvement can be carried out.

In short, Jane Fitts' law is instructive for designers of interactive software systems. It provides a quantitative model of the effect of target size and distance on operation time, helping designers optimize interface layout, provide better user experience, and evaluate and improve interaction performance.

List the applications of Fitts' law in Web page design.

Fitts' law has multiple applications in web page design, and the following are a few common application scenarios:

Navigation bar and menu design: According to Fitts' law, the width of the target has a significant impact on the accuracy and speed of clicking. In the navigation bar and menu design of the web page, the width of the target can be increased to make it easier for the user to click and improve the user's operation efficiency.
Button and Link Design: Buttons and links are one of the most commonly used interactive elements in web pages. According to Fitts' law, increasing the size of buttons and links can reduce the user's click error and improve the user's click accuracy. Therefore, when designing buttons and links, you need to consider their size and clickable area to provide a better user experience.
Form input design: In the form input design of web pages, Fitts law can be applied to optimize the layout and size of input fields. Placing commonly used input fields at a shorter distance enables users to complete input operations more quickly and improves input efficiency.
Scrollbar Design: For web pages with a lot of content, scrollbars are an important component for users to browse and navigate the page. According to Fitts' law, increasing the width of the scroll bar can improve the accuracy and speed of the user's operation on the scroll bar. Therefore, when designing a scroll bar, you can increase its width to make it easier for users to click and drag.
Responsive Design: The principles of Fitts' law apply to responsive design as well. On mobile devices, users may require more precision due to limited screen real estate. Therefore, when designing web pages on mobile devices, you need to consider the size and distance of the target to provide a better user experience.

In short, Fitts' law can help designers optimize the size, layout and distance of interactive elements in Web page design to improve user operation efficiency and accuracy. It can guide designers to create web pages that are easier to use and navigate, providing a good user experience.

Applying Fitts' law to analyze and compare the interaction efficiency of pie menu and ordinary drop-down menu

Applying Fitts' law to compare the interaction efficiency of pie menus and common drop-down menus can be evaluated by measuring click time and click accuracy. According to the formula of Fitts' law, the indicators of the two menu forms can be calculated and then compared.

Pie menu: The pie menu is a circular or fan-shaped menu, and the corresponding function or option can be selected by clicking on the position of the menu item. When applying Fitts' law, it is necessary to calculate the target width and distance of each menu item in the pie menu, and then calculate the click time according to the formula.
Common drop-down menu: The normal drop-down menu is a vertical or horizontal menu form, which is operated by expanding the menu list and selecting the corresponding option. When applying Fitts' law, it is necessary to calculate the target width and distance of each menu item in the drop-down menu, and then calculate the click time according to the formula.

By comparing the click time and click accuracy of the two menu forms, their interaction efficiency differences can be drawn. In general, pie menus can be more efficient with relatively large target widths and short distances, since the user can tap the desired menu item more quickly. However, a normal drop-down menu may be more suitable when there are a large number of options or where multiple levels of selection are required, as it provides more visible options and a clearer menu structure.

In practical applications, an experiment can be designed to compare the interaction efficiency of pie menus and ordinary drop-down menus. By recruiting a group of participants, having them perform a series of tasks using different types of menus, and recording data on click times and click accuracy. Then, through data analysis and statistical methods, the efficiency difference of the two menu forms is obtained, and suggestions for improvement are put forward based on the results.

It is worth noting that Fitts' law is only an indicator to measure the efficiency of interaction, and other factors, such as user experience, visibility, and task complexity, should also be considered to comprehensively evaluate the design of the menu.

When using Microsoft software, users can choose to add labels below the icons in the toolbar. Please explain why it is easier to click on a tool with a label (assuming the user knows what the tool does even without the label)

When using Microsoft's software, users can choose to add labels under the icons in the toolbar. The purpose of this is to enhance the recognizability and ease of use of the tools. Here are a few reasons why clicking on a labeled tool is easier:

Provide visible textual descriptions: By adding labels below tool icons, users can directly see a textual description of a tool, rather than relying solely on the icon's graphic to understand its function. This makes it easier for users to understand the purpose and function of the tool, especially for those users who are not familiar with the meaning of the icons.
Enhancing legibility: Icons may have some similarity or ambiguity in design, especially for tools that have a similar design or function. By adding labels, users can more easily distinguish and identify different tools, avoiding confusion and misuse.
Provide language support: In a multilingual environment, different users may use different languages, and there may be differences in the understanding and interpretation of icons. By adding tags, you can provide a textual description corresponding to the user's language, making the purpose of the tool clearer and more specific.
Provide auxiliary information: Labels can be used to provide additional auxiliary information, such as shortcut key tips, operation instructions, or status indicators. This information can help users better understand and use tools, improving efficiency and accuracy.

In general, by adding labels under the toolbar icons, more information and auxiliary functions can be provided to users, making the tools easier to identify and use. Although the user may already know the purpose of the tool, the presence of the label can provide additional visual support and language support to enhance the user's understanding and operation experience.

Table 8-3 Extended Set of Keystroke Hierarchical Model Operators Keystroke 230μs Aim the mouse at the target 1500μs Hold the mouse 360μs Perception 100μs Eye saccade 230μs Retrieve memory 1200us Mental preparation 70μs Choose a method 1250us

The basic time is as above, please answer and calculate "If you want to add the word "not" to the English sentence "I do like using the keystroke level model." to make it into "I do not like using the keystroke level model". Apply click The key hierarchy model predicts the execution time of the task (assuming that the current user's hand is on the keyboard, and the insertion position is selected by the mouse at the same time)."

Based on the extended set of keystroke hierarchy model operators in Table 8-3 and the given basic time, we can perform the following calculations to estimate the execution time of the task:

Input the character "not": According to the keystroke hierarchy model, the input time of each character is 230μs. Therefore, the time to enter "not" is 3 * 230μs = 690μs.
Aim the mouse at the target: according to Table 8-3, the time to aim the mouse at the target is 1500μs.
Holding the mouse by hand: According to Table 8-3, the time for holding the mouse by hand is 360μs.
Perceived eye saccade: According to Table 8-3, the time to perceive eye saccade is 230μs.
Retrieve memory: According to Table 8-3, the time to retrieve memory is 1200μs.
Mental preparation: According to Table 8-3, the time for mental preparation is 70μs.
Select a method: According to Table 8-3, the time to select a method is 1250μs.

Add up these times to get the predicted execution time for the entire task:

690μs (type the character "not") + 1500μs (point the mouse to the target) + 360μs (hold the mouse) + 230μs (perceive eye saccades) + 1200μs (retrieve memory) + 70μs (mental preparation) + 1250μs (choose a method) = 5300μs

Therefore, according to the prediction of the keystroke level model, the word "not" is added to the English sentence "I do like using the keystroke level model." and the keystroke level model is applied to predict the execution time of the task. The estimated execution time of the task is 5300μs.

Chapter nine

What issues should be paid attention to in user participation design?

In the user participation design process, the following issues need to be paid attention to:

Clear and well-defined goals: Make sure that the goals and objectives of the design are clearly defined, and it is clear what the specific goals of the user's participation in the design are. This helps ensure that the process and outcomes of user engagement are aligned with design goals.
Appropriate Stages of Engagement: Determine the appropriate stages and timing for user engagement. Users can participate in the design process at different stages such as requirements gathering, prototyping, and user testing. Make sure the timing of user engagement is appropriate for them to provide valuable feedback and input.
Diversified user participation: Include users of different types and backgrounds as much as possible to participate in the design process to obtain more comprehensive feedback and opinions. Consider the needs and preferences of different user groups to ensure an inclusive and user-friendly design.
Open communication and cooperation: Establish open communication channels to encourage users to actively participate and provide feedback and opinions. Maintain a good working relationship to ensure effective interaction and collaboration between the design team and users.
Focus on user experience: In the process of user participation in the design, always put user experience in the first place. Pay attention to the needs, expectations and feedback of users to ensure that the design results can meet the actual needs of users.
Respect and protect user privacy: When users participate in the design process, respect users' privacy and personal information protection. Ensure that users' participation is voluntary, and take appropriate measures to protect users' personal information and data security.
Reasonably handle user feedback: listen carefully to and consider user feedback and opinions, and take appropriate actions. The purpose of user participation in design is to improve and optimize the design, thus responding and improving appropriately to user feedback.

Overall, user engagement in design is an important activity that can help design teams better understand user needs, improve designs, and deliver better user experiences. Therefore, the above-mentioned issues need to be paid attention to in user participation design to ensure that user participation is meaningful and effective.

chapter Ten

Why is it important to conduct small-scale trials, and what are the roles and practical implications?

Conducting small-scale trials is an important and practical part of the design and development process, for several main reasons:

Validate design assumptions: Small-scale experiments can help validate assumptions in design and development. Through practical testing and observation, it is possible to understand how users interact with a product or system to verify whether design decisions and assumptions are valid.
Spotting problems and bugs: Piloting on a small scale can help uncover potential problems and bugs. By involving users in testing, they can provide feedback and opinions about a product or system. This helps to identify design issues, user experience obstacles, or functional flaws and improve them in a timely manner.
Adjust the design in advance: Small-scale experiments can detect problems and make adjustments in the early stages of design and development. This helps reduce the cost and effort of later revisions and adjustments. By adjusting the design in a timely manner, major problems that are not discovered until after the product is released can be avoided.
Evaluate user experience: Pilots can evaluate user experience and satisfaction. By observing users' behavior and collecting feedback and opinions, it is possible to understand their feelings and experience with a product or system. This helps improve user interface, interaction flow, and feature design to provide a better user experience.
Optimize product iterations: Small-scale experiments can help iterate and optimize products. Through multiple experiments and feedback collection, the design can be gradually improved, and the functions and performance of the product can be continuously optimized to meet the needs and expectations of users.

In summary, conducting small-scale trials is critical to the design and development process. It can validate design assumptions, find problems and defects, adjust designs ahead of time, evaluate user experience, and optimize product iterations. Through such an iterative cycle, the product can be continuously improved and optimized, providing a better user experience, and increasing the success and acceptability of the product.

Chapter 11

What information do you think is important when conducting observation activities? Please try to come up with a new observation framework

Here are some important messages and recommendations when conducting observation activities, as well as a proposal for a new observation framework:

Important information:

User Behavior: Observe user behavior and actions, including their steps, clicks, scrolling, typing, etc. Recording user behavior can help in understanding how they interact with a product or system.
User Feedback: Listen to verbal feedback and comments from users, issues they may have mentioned, likes and dislikes, and any suggestions or comments.
User emotions: Observe user emotions and expressions, including their satisfaction, confusion, frustration, or excitement. Emotional responses can provide important clues about user experience.
User Pain Points: Identifying difficulties, obstacles, or pain points that users may encounter can help improve the design and provide a better user experience.
Contextual information: Record the background and environmental information of the observation activities, such as usage scenarios, time, location, equipment, etc. This contextual information can provide a more comprehensive understanding and interpretation of user behavior.

Proposal for a New Observation Framework: The following is a new observation framework consisting of three main dimensions:

User Behavior Dimensions:
- Operation process: record the user's operation steps and processes, including page switching, function usage sequence, etc.
- Interaction behavior: observe the user's click, slide, drag, input and other interactive behavior, including the accuracy and efficiency of the operation.
- Bugs and Pain Points: Identify errors, confusion, or pain points that users may encounter, and record relevant details.
User Experience Dimensions:
- Emotional responses: Record the user's emotional responses, including satisfaction, excitement, confusion, or frustration.
- Feedback and Comments: Record user verbal feedback and comments, including likes, dislikes, suggestions, etc. mentioned by users.
- User Experience: Evaluate the user's overall experience with the product or system, including ease of use, efficiency, and satisfaction.
Context dimension:
- Usage scenario: record the specific usage scenarios and background information of the observation activities.
- Device and environment: Record the device type, screen size, environmental noise and other related information used by the user.
- User characteristics: collect basic information and characteristics of users, such as age, gender, skill level, etc.

By combining this new observation framework, users' behavior, experience, and contextual information can be observed and analyzed more comprehensively. This helps identify issues, improve the design, and provide a better user experience. At the same time, ensure that user privacy and confidentiality are protected during observation activities, and that appropriate ethical and legal regulations are followed.

Why do you need to use the talking-by-doing approach when applying observation techniques, and what problems does it solve?

Using the talking-by-doing approach when applying observation techniques can be very beneficial and address the following questions:

Record detailed information: The talking-by-doing method helps observers record their feelings, attentions, and details of observations during the observation process. This can ensure that the observer will not forget important observation information, and can conduct accurate analysis and summary later.
Provide additional background information: By talking by doing, the observer can provide some additional background information during the observation process, such as the purpose of the system, user needs, and environmental constraints. This information can help others better understand the context and context of the observations and thus interpret the observations more accurately.
Understanding user thought processes: Talk-by-doing methods help observers articulate their thought processes and decision-making processes. This is very important for understanding the user's mental model, thinking style and decision-making basis. Through the observer's language expression, we can better understand the user's thinking and decision-making process when using the system.
Spotting Potential Problems: Talking-by-doing can help observers spot and record the problems, difficulties, and doubts they observe in a timely manner. This helps to identify potential problems with the system and challenges of users during the observation process, so that improvements and optimizations can be made during the design and development process.
Facilitates communication and collaboration: The talk-by-doing approach facilitates communication and collaboration between observers and other team members (e.g. designers, developers, researchers, etc.). Oral presentations allow for more direct sharing of observations and findings with others, facilitating deeper discussions and collaborations.

All in all, the talk-by-doing approach can help observers record important information during the observation process, provide context, understand user thought processes, identify problems, and facilitate teamwork. It improves the effectiveness and quality of observations and ensures the accuracy and comprehensibility of observations.

What is the purpose of conducting interviews with users after observation?

Post-observation interviews with users serve the following purposes:

Gain a deep understanding of user needs and experiences: Interviews are an opportunity for evaluators to learn more about users' needs, expectations, and experiences. Dialogue with users allows in-depth exploration of their perspectives, feelings, and feedback to gain a more complete understanding of their needs and usage context.
Obtain users' subjective opinions and feedback: Observation can only provide the evaluator's own observations, while interviews can provide users' subjective opinions and feedback. Users can share their preferences, dissatisfaction, suggestions, etc., which is valuable information for evaluators and can be used to improve the design and function of a product or system.
Validate observations and assumptions: Interviews with users can validate previously observed behaviors and responses, and further confirm whether the evaluator's assumptions and inferences are correct. Interviews can help evaluators ensure that the understanding of user behavior and experience is accurate and fill in possible information gaps.
Provide explanation and further exploration: The interview is an opportunity for the evaluator to provide feedback and explanation to the user. If evaluators observe questionable or incomprehensible user behavior or responses, they can conduct interviews to gain further insight into user motivations, intentions, and psychological processes.
Build user engagement and partnerships: By conducting interviews with users, evaluators can build active user engagement and partnerships. Interviewing is the process of communicating and interacting with users that helps build trust and understanding, making users feel important and respected.

Overall, the purpose of post-observation interviews with users is to further understand user needs and experiences, obtain users' subjective opinions and feedback, verify observations and hypotheses, and establish positive user engagement relationships. These purposes help to provide more accurate, comprehensive and valuable evaluation results, and promote the improvement and optimization of products or systems.

Try to answer the question "When is observation sufficient".

When observations are sufficient is a relative question, as it depends on the purpose of the assessment, the scope of the study and the resources available. However, the following are some guidelines that can help determine whether observations are adequate:

Goal Achieved: Observing whether enough information has been collected to answer the key questions of the study or evaluation. Observation can be considered sufficient if the required information has been obtained.
Data Saturation: Whether the observed data is rich and diverse enough to capture important aspects of user behavior and experience. Observations can be considered sufficient if no new key information or patterns emerge.
Statistical significance: If statistical analysis is used, the principles of statistics can be used to determine whether observations have been sufficient. For example, calculate the required number of observations by factors such as sample size, confidence level, and effect size.
Feedback and Consistency: Whether the observation was consistently confirmed or fed back by multiple observers. Observation can be considered sufficient if multiple observers have reached consistent conclusions and the observations are stable and reliable.
Time and resource constraints: The time and resources available for observation are limited. In practical situations, evaluations need to be performed within time and resource constraints. Observation can be considered sufficient if the available time and resources have been fully utilized and meaningful results obtained.

It should be emphasized that the adequacy of observation is a process of judgment and compromise, which needs to be considered comprehensively according to the specific situation and the purpose of the evaluation. It is important to ensure that observations gather enough information to support the goals of the assessment and provide meaningful insights and feedback for design and improvement.

Please draw an interface of the student performance management system from the perspective of human-computer interaction, and add the voice recognition function, and describe the functions in the screen

Interface description: The interface design of the student performance management system should be simple, intuitive, and easy to use. The following is a possible interface description:

Head navigation bar: Contains system logos and main navigation menus, such as home page, student management, course management, grade entry, etc.
Student List: Display the basic information of all students, such as name, student number, etc., and provide related operations, such as buttons to add, edit, and delete student information.
Course list: Display information of all courses, such as course name, credits, etc., and provide related operations, such as buttons to add, edit, and delete course information.
Grade entry form: used to enter student grade information. The columns of the table represent different courses, and the rows represent different students. Each cell allows the input of grade data.
Grade Statistical Chart: Display the distribution of students' grades in the form of graphs, which can be histograms, line graphs, etc., to intuitively understand students' grades.
Search and filter function: provide a search box and filter conditions to quickly find and filter students or courses for easy management and operation.

Voice recognition functionality: To add voice recognition functionality, a voice recognition button or icon can be added to the interface, allowing users to interact with the system by voice. After the user can click the voice recognition button, the system starts to receive and recognize the user's voice input.

The application scenarios of speech recognition function can include:

Voice input grades: Users can input students' grades by voice, and the system will recognize and automatically fill in the corresponding grade entry form.
Query student information: The user can make a query request by voice, such as "find the student information whose student number is xxx", the system will perform corresponding search operations and display the results according to the voice recognition results.
Control system functions: Users can perform system functions through voice commands, such as "add students", "edit course information", etc., and the system will perform corresponding operations according to the voice recognition results.

By adding voice recognition function, the student performance management system can provide more convenient and diversified interaction methods, and improve user experience and operational efficiency.

Give a specific example with a detailed calculation process

Suppose we have a simple state transition network with three states: A, B, and C. We wish to compute the steady-state distribution of the system. Given the following state transition probabilities:

The probability of moving from state A to state B is 0.2
The probability of moving from state A to state C is 0.8
The probability of moving from state B to state A is 0.5
The probability of moving from state B to state C is 0.5
The probability of moving from state C to state A is 0.3
The probability of moving from state C to state B is 0.7

The specific calculation process is as follows:

Determine the state space: The state space is {A, B, C}.
Build the state transition matrix:

State transition matrix P = | 0 0.5 0.3 |

| 0.2 0 0 |

| 0.8 0.5 0.7 |

· Initialize the initial probability distribution: Assume that the initial probability distribution is [1, 0, 0], indicating that the initial state of the system is A.

Iteratively compute the steady-state distribution:

The first iteration: Multiply the initial probability distribution vector [1, 0, 0] with the state transition matrix P to obtain a new probability distribution vector [0, 0.2, 0.8].
The second iteration: multiply the new probability distribution vector [0, 0.2, 0.8] with the state transition matrix P to get the new probability distribution vector [0.5, 0.08, 0.42].
Continue to iterate until the probability distribution vector no longer changes significantly.

Through multiple iterative calculations, we finally get the steady-state distribution:

Steady state distribution = [0.625, 0.125, 0.25]

It means that the probability of the system staying in state A, B and C stably after a long time running is 0.625, 0.125 and 0.25 respectively.

Through the above calculation process, we get the steady-state distribution of the system, so that we can understand the probability of the system staying in different states, and provide reference for subsequent decision-making and optimization.