# Crystal clear: Machine Learning

13/05/2020

Tags: datasetmachine-learningtrain-test-splitcrystal-clear

In the real world, we can perform measurements, which provide us with data. Measuring a quantity X once gives you a measurement m*{X, 1}. Measuring it n times gives you a sequence of measurements m*{X, 1}, m*{X, 2}, … m*{X, n}. Now let’s try measuring multiple quantities X_1, X_2, …, X_M. Doing so n times gives a sequence of sequences of measurements. Let us denote the sequence of measurements for quantity X_i with M_i. We have M_1, …, M_M.