29Facing Degrees of Freedom

I have mentioned “degrees of freedom” but I wrote that we would address it later. Later is now. Below is part of what I wrote while explaining the basics of the sample variance statistic:

  1. To get the variance, we do the following…(don't worry about why 1 is subtracted from the sample size for now.)
  2. The symbol for the sample variance is img.
  3. Here is the sample variance calculation in math shorthand.
equation

Notice again that the formula for sample variance has img as a denominator. This term is the degrees of freedom.1 In the above formula, the degrees ...

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