In Machine learning, KNN (K-nearest neighbors) is a type of supervised learning algorithm that can be used for both classification and regression tasks. For KNN, we need to initialize the hyperparameter K. Later algorithm will calculate the distance between all the observations of the training dataset with the current observation in the test dataset. Then the algorithm picks the observations with the highest K distances. If it is a regression task, the algorithm returns the mean of K classes. If it is a classification task, the algorithm returns the mode of K classes.
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