This free online video program "lays out the parts of the confidence interval and gives an example of how it is used to measure the accuracy of long-term mean blood pressure. An example from politics and population surveys shows how margin of error and confidence levels are interpreted. The program also explains the use of a formula to convert the z* values into values on the sampling distribution curve. Finally, the concepts are applied to an issue of animal ethics." This individual video is accessed by scrolling down to the "Individual Program Descriptions - 19. Confidence Intervals" and click the "VOD" icon at the top-right of the description.