Standard Deviation normalization of data in data mining

Standard Deviation normalization of data in data mining

Just like the Z score, and Min-Max, data can also be normalized with standard deviation.

Different values in the data set can be spread here and there from the mean. Variance tells us how much far away are the values from the mean.

Standard deviation is the square root of the variance.

High standard deviation

High standard deviation tells us that more numbers are far away from the mean.

Low standard deviation

Low standard deviation tells us that fewer numbers are far away from the mean.

The formula to calculate the standard deviation of sample and population

standard deviation formula
Figure: standard deviation formula

How to calculate variance and standard deviation of a population data?

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z score normalization standard deviation
Figure:  standard deviation

Mean = 13.25

Variance = 21.6

Standard deviation = 4.6