Sample variance and population variance: which of the two?

Published at November 9, 2018 · 7 min read

Teaching experimental methodology in agriculture related master courses poses some peculiar problems. One of these is to explain the difference between sample variance and population variance. For the students it is usually easy to grasp the idea that, being the mean the ‘center’ of the dataset, it is relevant to measure the average distance to the mean for all individuals in the dataset. Of course, we need to take the sum of squared distances, otherwise negative and positive residuals cancel each other out....