Scala for Machine Learning(Second Edition)
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Mathematical notations for the curious

Each chapter contains a small section dedicated to the formulation of the algorithms for those interested in the mathematical concepts behind the science and art of machine learning. These sections are optional and defined within a tip box.

For example, the mathematical expression of the mean and the variance of a variable, X, as mentioned in a tip box will be as follows:

Note

Convention and notation

This book uses the 0 zero-based indexing of datasets in mathematical formulas.

M1: A set of N observations is denoted as {xi} = x0, x1 …., xN-1 and the arithmetic mean value for the random value with xi as values is defined as: