Khan Academy: Statistics: Small Sample Size Confidence Intervals

Where do all of these equations come from? A statistics video explains how to find the sample size equation based on the formula for the confidence interval. 

There are too many equations to memorize, but a helpful trick will make it easier. When you start with the confidence interval equation, the video walks through how to solve it and create the sample size equation.

Be confident about your ability to understand statistics. The 20th installment of the Crash Course Statistics playlist, the informative YouTube video describes the meaning of confidence intervals and how they relate to normal...

Constructing small sample size confidence intervals using t-distributions.

Constructing small sample size confidence intervals using t-distributions.

Video demonstrates using t-statistics to answer a question involving hypothesis testing with a small sample. Explains how to read a t-table and use it for a one-tailed test. [9:04]

Video demonstrates using t-statistics to create a 95% confidence interval for a small sample size. [11:47]

Video discusses the effect of sample size on the sampling distribution. Shows using a simulation how as sample size increases the sampling distribution becomes more normal and the standard deviation decreases. Also discusses the effect...

Video reviews the central limit theorem and uses a simulation to illustrate sampling distributions and how they approach a normal distribution with larger sample sizes even if the original distribution was not normal. Also discusses the...

This lesson looks at what effects changing the standard deviation, confidence level, and/or sample size have on the width of a confidence interval. Includes downloadable study guide with exercises - guide also covers other topics. [11:26]