Descriptive Statistics

Mean, Median, and Mode of the Geyser Data

In this activity, you will be calculating the mean, median, and mode for the eruption data of the Old Faithful Geyser, located in Yellowstone National Park in Wyoming. Its name reflects the fact that it erupts on a very regular basis. The data consists of the number of the eruptions and length of time between them, collected over 16 days. Using Excel (the TI-83 is excluded from this activity because of its inability to deal with such a large data set), calculate the mean, median and mode for both the duration of the eruptions and the interval between the eruptions.

This data exists in two files: one is in Excel Data format and one is in Text format.

What is the mean duration of the eruptions? Is the median duration much different from the mean duration? What is the most frequent length of the eruptions? If you went to Yellowstone National Park to see Old Faithful, how long would you expect to sit and wait between eruptions of the geyser?

Sometimes, looking at data sets in a different way can reveal some interesting traits that were not detected by an initial analysis. Try generating a scatter plot of duration data set and see what you discover!