JB I discuss the sampling distribution of the difference in sample proportions, and confidence intervals and hypothesis tests for the difference in population proportions (using large sample Z procedures based on the normal approximation). The male birth rate data is from: Koshy et al. (2010). Parental smoking and increased likelihood of female births. Annals of Human … Read more
I work through an example of a confidence interval and a hypothesis test for the difference in population proportions (based on the normal approximation). The example involves an experiment investigating a possible effect of magnetic pulse on the ability of homing pigeons to navigate. The data used in this video is taken from: Holland et … Read more
I introduce the chi-square test for one-way tables (sometimes called a goodness-offit test), and work through an example. The data used here is from a classic 1905 genetics experiment by William Bateson and Reginald Punnet.
I work through an example of testing the null hypothesis that the data comes from a binomial distribution. I do this for two tests, one in which the probability of success is specified in the null hypothesis, and one where it is estimated from the data.
I introduce the chi-square test of independence and work through an example.
I work through an example of finding the p-value for a chi-square test, using both the table and R.
I discuss confidence intervals and hypothesis tests for a variance when sampling from a normally distributed population. I discuss the logic behind the procedures, discuss some characteristics of the sampling distribution of the sample variance, and give the appropriate formulas. I briefly discuss the results for an example problem, but I don’t work through any … Read more
I work through an example of a confidence interval and a hypothesis test for a variance (using chi-square methods that are appropriate when sampling from a normally distributed population). The cereal data is from a sample of 15 bags of cereal I collected and weighed. I have a video introduction to these procedures available at: … Read more
I derive the appropriate formula for a confidence interval for a population variance (when we are sampling from a normally distributed population). I do not do any calculations or look at any examples in this video, I simply derive the appropriate confidence interval formula. I work through an example at http://youtu.be/tsLGbpu_NPk
A discussion of the sampling distribution of the sample variance. I begin by discussing the sampling distribution of the sample variance when sampling from a normally distributed population, and then illustrate, through simulation, the sampling distribution of the sample variance for a few other distributions.