The company wants to implement standardized project management, so it began to supplement the knowledge of project management. The production of this article refers to the following materials:
http://wenku.baidu.com/view/80e6e510f18583d0496459d7.html Introduction and application of function point estimation method
http://wenku.baidu.com/view/305929d428ea81c758f578da.htmlSoftware function point estimation.xls
http://www.zhihu.com/question/19842309How to calculate the project duration?
http://blog.sina.com.cn/s/blog_6314f2690100h8bu.html CT_On the estimation method of software development workload
I would like to thank the original author and porter of the above article.
The following content is not necessarily correct, and it is your own understanding, and you are welcome to make bricks.
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1. 9:30 - 11:30 = 2 hours every day, 14:00 - 17:00 = 3 hours, this time period should be called the golden working time, a person's effective working hours in a day = 8 × (1 - 10%) × (1-30%) ≈5 h
10% of which is working time offset by communication costs
30% of working time offset by other transactions
2. The level of project members varies, and the project manager or R&D manager has many trivial things, so it cannot be calculated as 5 working hours per day. If the person who can fully meet the job requirements is 1 point, then:
Good level: 5 hours * 1.2 = 6 hours
Normal level: 5 hours * 1 = 5 hours
Average level: 5 hours * 0.8 = 4 hours
R&D manager: 5 hours * 0.8 = 4 hours
Daily effective working hours of the project team = (R&D manager*n1*0.8+average level*n2*0.8+normal level*n3*1+good level*n4*1.2)*5h
Where n1, n2, n3, n4 are the number of people
3. Estimate working hours according to WBS (the most accurate estimation of some function points in development is to use FP estimation)
PR—— Design : Coding&UT : IT&ST = a : b : c
Estimation steps: (Reference:
http://wenku.baidu.com/view/305929d428ea81c758f578da.html
)
a. Perform size estimation to get the FP number (FP).
Fill out the "Size Estimation (FP)" worksheet
b. According to the number of FPs, the total number of rows (SLOC) is obtained.
Fill out the "Size Estimation (FP)" worksheet. The total number of rows is calculated by the following formula:
(LPFP is SLOC/FP, and this coefficient represents the number of lines of code required to implement each function point)
Total rows = FP * LPFP
c. Determine the size estimate
Fill out the "Size Estimate Summary" worksheet
d. Estimate the workload and get the number of man-days.
Fill out the "Effort Estimate (Productivity)" worksheet. Calculated according to the following formula:
Coding&UT workload = total number of lines (SLOC) / LPD
Calculate the total workload of each stage of the project according to the workload ratio (PR) of each stage of development:
Total project workload = (a+b+c)/b * Coding&UT workload
e. All participants discuss whether the working hours in WBS are reasonable, remove the singular value and take the average (this step can be repeated, according to statistical principles, a large number of endless repeated behaviors, the average result obtained is very close to the real value.)
f. Determine the size estimate
Fill out the "Summary of Workload Estimates" worksheet
4. According to the comparison between the workload (unit: man-day) and the time expected by the customer, adjust the priority of the function points, and comprehensively measure the implementation plan
This workload is a relatively real reference value, so when considering such links as personnel, construction period, and resource input ratio, this workload should be taken as an important indicator and included in it.
5. The workload A can be used to calculate the actual completion date by combining the "effective daily working hours of the project team" in item 2
The rough estimate is: project execution time = A*8 / daily effective working hours of the project team / 22 working days per month
However, this estimation method has a large deviation. Because the human resources invested in each stage of the project are different, the actual daily effective working hours of each stage are also different. The correct calculation method should be based on the personnel invested in each stage of the project implementation. to calculate the actual daily effective hours for each phase to calculate a less biased estimate.
Project execution time closest to actual value = (Σ((function point i*complexity coefficient*ΣDI*LPFP / LPD )*8 / daily actual effective working hours of function i))/22 working days per month
6. Others:
a. Overtime:
The golden overtime hours are: 19:00 - 21:00 = 2 working hours, which is included in the effective working hours of a single person per day
Daily effective working hours of the current project team = F (number of people n, ability level coefficient, original single effective working hours per day + 2)
b. Add people:
Because of the increase in communication costs, for the time being, adding 1 person will reduce the overall efficiency by 10%:
Effective working hours of the current project team =
(Daily effective working hours of the original project team + F (number of people, ability level coefficient, single effective working hours per day))*(1-10%)^n