Classification and regression algorithms for machine learning

Preface: According to the target value of the machine learning data set is discrete or continuous, the processing algorithm includes classification and regression.

sklearn tutorial  https://www.jianshu.com/p/6ada34655862

table of Contents

Classification algorithm

k-nearest neighbor algorithm

Naive Bayes

Decision tree, random forest

Classification regression

Regression algorithm

Linear regression


Classification algorithm

k-nearest neighbor algorithm

Algorithm idea: A sample is the most similar to the k samples in the data set. If most of the k samples belong to one category, then the sample is recognized as belonging to this category;

The most common representation of the distance between two points or between multiple points, also known as Euclidean metric, is defined in Euclidean space. The Euclidean distance between two points x1(x11,x12,…,x1n) and x2(x21,x22,…,x2n) in n-dimensional space

achieve:

https://www.cnblogs.com/xiaotan-code/p/6680438.html

from sklearn.neighbors import KNeighborsClassifier
# 导包

knn = KNeighborsClassifer()
# 定义一个分类器对象

knn.fit([特征值],[目标值])
# 调用模型

Naive Bayes

Algorithm idea: https://blog.csdn.net/Growing_hacker/article/details/89790230

achieve

from sklearn.naive_bayes import MultinomialNB
# 导包


clf = MultinomialNB()
# 实例化分类器


clf.fit([特征值],[目标值])
# 调用训练模型

https://blog.csdn.net/Growing_hacker/article/details/89790230 

 

Decision tree, random forest

Algorithm idea: According to information entropy and information gain, find out the classification standard

https://blog.csdn.net/Growing_hacker/article/details/89816012

achieve

from sklearn.tree import DecisionTreeClassifier
from sklearn.ensemble import RandomForestClassifier
# 导包

 

Classification regression

Algorithm idea: To solve the two-classification problem, the result of linear regression is used as the input of classification regression, and the maximum likelihood loss function is used to find the weight. Different thresholds produce different prediction results

achieve

from sklearn.linear_model import LogisticRegression 
# 导包

classifier = LogisticRegression(random_state=37) 
# 实例分类器对象
  
classifier.fit(X, y) 
# 回归分类器进行训练  

Regression algorithm

Linear regression

Algorithm idea: According to the loss function, continuously adjust the weight to make the value of the loss function smaller; solve the weight by the characteristic equation or gradient descent method

https://www.cnblogs.com/geo-will/p/10468253.html

achieve

from sklearn.linear_model import LinearRegression

 

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Origin blog.csdn.net/Growing_hacker/article/details/104648562