A standard deviation seems like a simple enough concept. It’s a measure of dispersion of data, and is the root of the summed differences between the mean and its data points, divided by the number of data points…*minus one to correct for bias*.

This is, I believe, the most oversimplified and maddening concept for any learner, and the intent of this post is to provide a clear and intuitive explanation for Bessel’s Correction, or n-1.

Heliometer for Measuring Stellar Parallax, First Achieved by Friedrich Wilhelm Bessel, Public Domain

To start, recall the formula for a population mean:

Population Mean Formula

What about a sample mean?

#mathematics #statistics #data-visualization #data-science #jupyter-notebook

1.25 GEEK