Comparing means

On watching this video, students should be able to:

1. Identify settings that involve independent samples and paired samples and know that each requires a different statistical method.
2. Distinguish between the t-distribution and normal distribution and explain when and why a t-distribution should be used.
3. Describe the effect the t-distribution will has on a confidence interval and a p-value from a hypothesis test compared to the normal distribution and appreciate why this is sensible for smaller sample sizes.
4. Confirm that when comparing groups we should choose a population parameter that quantifies this comparison and provides a measure of effect, such as the mean difference. Hence, estimating population parameters such as a mean in each group does not allow a direct comparison or provide a measure of effect.
5. State the basic form of a confidence interval and test statistic, and appreciate that these can be applied to many different settings.
6. Interpret the results of these analyses in the context of the original research question.
7. Confirm that these methods rely on assumptions about the data that must be checked and that other methods should be investigated when these assumptions are not met.