K-Means clustering algorithm

Clustering:

K-Means algorithm:

star shaped things are centroids

How it works:

Expectation — maximization :

Graphical Explanation :

blue dots are data points
the star shaped points are centroids here.
this is handmade example plots. please forgive us for not being accurate

Evaluation methods

Elbow method

  1. it executes the the k-means clustering on the given dataset for different values of k (generally ranges from 1 to 10)
  2. for each value of k , calculates the WCSS value
  3. plots a curve between K value and WCSS value
  4. the sharp point of bend or the point of the plot looks like an arm then that point is considered as optimal value of K.

Silhouette Analysis

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