Statistical Applets

Choose a data set on the first tab below, then click the other tabs to view or manipulate the data, see summary statistics, or view a histogram or stemplot of the data.

Click the "Quiz Me" button to complete the activity.

The pattern of variation of a variable is called its distribution. The shape and spread of a distribution can be displayed graphically or summarized by descriptive numerical values.

This applet calculates standard numerical statistics (e.g., mean, standard deviation, quartiles) and shows graphical displays (a histogram and a stemplot) of one-variable data sets. You can choose to view data sets from your book, or enter your own set of data.

Choose "User-entered data" as the dataset, then enter the following values:

13, 7, 11, 5, 7, 12, 11, 9, 11, 10

Enter the following statistics for this dataset (accurate to within 2 decimal places):

- Standard deviation: 80KJ65Wsj5A=
- Mean: jTjfVZyUvtg=
- n: Pz2PEfhsNWI=
- Median: 4dtNmqXeVHM=

3

Try again.

Incorrect. See above for the correct answers.

Great job.

Now inspect the histogram for the dataset. Set the lower value to 0, the upper value to 15, and the number of classes to 5.

Enter the lower and upper values of the class in the histogram that contains the greatest number of values. Lower value: Q3PdQ4iKdKE=; Upper value: DDH6Tw1RFEk=

Does the distribution of this dataset appear symmetrical in this histogram? sjkhLuRCQ4SijoxQ

3

Try again.

Incorrect. See above for the correct answers.

Great job.

To determine the mode -- the most common value -- in this dataset, all you have to do is look at which "stem" has the most "leafs" to the right of it. The modal value here is 11.