sample-variance

If (we can assume) the population is normal, then the chi-square distribution can be used to test the sample variance (this is analogous to using the student's t for a test of the sample mean). David's XLS: http://trtl.bz/011018-yt-sample-variance-xls

Hi all ... I want to know why we need sample variance when we already have our 'regular' formula for calculating variance. The following extract is from Miller, Chapter 3 ... Basic Statistics

Learning objectives: Calculate and interpret the sample mean and sample variance. Construct and interpret a confidence interval. Construct an appropriate null and alternative hypothesis, and calculate an appropriate test statistic. Questions: For the following questions, please feel free to...