Old Faithful

For a more detailed discussion, see the description in The Practice of Statistics, Statistics and Probability with Applications, or Introductory Statistics: A Student-Centered Approach.

The scatterplot below displays data for all 263 eruptions of Old Faithful in one month. The population regression line, Predicted wait time = 33.3 + 13.3 Duration, is shown as a solid line. To investigate the sampling distribution of the sample slope, the applet will select a random sample of n eruptions, display the sample regression line as a dashed line, and record the value of the sample slope.