Lecture video for “Data Sense: An Introduction to Statistics for the Behavioral Sciences” by Barton Poulson. This video covers Chapter 07: Estimation, Section 07: Influences on Confidence Intervals. It explains how the width of confidence intervals – which translates to their precision – is directly affected by the chosen confidence level, the standard deviation, and the sample size. The book and complete set of videos may be purchased at http://kendallhunt.com/poulson/.