Regression and classification are both supervised machine learning techniques that use known data to make predictions. Where they differ is in what type of question you want answer, and how your output data is structured. For example, do you want discrete, categorical answer choices, like yes/no, or a range of possible values from 0 to 100? This one picture shows the basic differences between the two methods.
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kNN
Decision Trees
Regression Analysis
References
Logistic Regression
Credit: Data Science Central By: Stephanie Glen