These provide links to a wide variety of relevant external websites. Explore the Stat Links to check, and extend, your understanding of the course material.

• This site provides a description and demonstration of what the mean and median of a distribution represent.
  After the web page loads, first read the instructions on the right hand side of the page. Then click the "Begin" button on the left hand side of the page. This will bring up a new window. In this window, focus on the instructions on the right hand side and the histogram in the top left corner (do not worry about the table in the bottom left corner). Click on the histogram to add additional scores to the distribution. What happens to the standard deviation if you add scores that are close to the mean? What happens to the standard deviation if you add scores far away from the mean?
  

• Take part in a quick and fun experiment that provides an illustration of the mean and standard deviation (and histograms too).
  Before you begin, think about how you might expect your mean and standard deviation values to differ for the small and large boxes. When the results window appears, focus on the mean and standard deviation (SD) (and the histograms too). Are the results as you expected?
  

• This brief article discusses the median and skewed distributions in the context of a real-life event (cancer diagnosis).
  
  

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