I work through an example of a confidence interval and a hypothesis test for the ratio of population variances, using F procedures that are based on the assumption of normally distributed populations.

The example in this video involves tail lengths of male and female lizards. The summary statistics and distributions of the tail lengths were estimated from Table 1 and Figure 2 in:

Qu et al. (2011). Sexual dimorphism and female reproduction in two

sympatric toad-headed lizards, \emph{Phrynocephalus frontalis}

and \emph{P. versicolor} (Agamidae). Animal Biology. 61:139-151.