stats

Having no background in statistics, understanding what a random variable is was a nightmare for me. The funny part was when I realized that, in the end, a random variable can be different things, but never exclusively a single one (I am aware this is not helpful).

What’s the relationship between population variance, sample variance and sample size? This question is pretty broad, and opens up to a lot of interesting issues that have challenged my understanding of the relationship between sample size, variance and bias of estimators.

Lot of people, including me, are struggling with the concept of (or idea behind) confidence intervals. One possible explanation is that understanding confidence intervals requires some capacity of abstract thinking. In the frequentist world, a parameter is a fixed, deterministic number, while an estimator (such as the average) is, by definition, a function of the data and, as such, its value changes from one sample to another (i.