# Find Sample Standard Deviation Using Python

## Sample Standard Deviation:

Sample Standard Deviation is one of the measures of dispersion that is used to estimate the Population Standard Deviation.

Sample Standard Deviation is calculated by taking positive square of root of the Sample Variance.

The formula for Sample Standard Deviation is

s = ∑(i=1 to n) √ (Xi-X̄)/(n-1)

stdev(data)

## Method Overview:

The python stdev() function takes a sequence or an iterator as the parameter that provides the sample data and returns the standard deviation.

## Exceptions:

Python raises a StatisticsError if the data passed inside the stdev() function has less than 2 items.

## Python example program to find Sample Standard Deviation of a distribution:

 # import the statistics module import statistics   sampleData = [120,125,123,126,132,124,122,128]   #Find standard deviation of the sample data sampleSD = statistics.stdev(sampleData)   print("Standard deviation of the sample data is %.2f"%(sampleSD))

## Output of a Python example program that finds the Sample Standard Deviation of a distribution:

 Standard deviation of the sample data is 3.74