BrownMath.com → TI-83/84/89 → Box-Whisker TI-89
Updated 7 Nov 2020

# Box-Whisker Plots on TI-89

Summary: You can use your TI-89 to create a box-whisker diagram, also known as a boxplot. Boxplots give you a general idea of the shape of the data, particularly its skew, and they highlight outliers in the data set.

Alternatives: If you have a TI-83/84, see Box-Whisker Plots on TI-83/84 or use MATH200A Program part 2.

Let’s make a boxplot of this data set:

 11 15 14 12 9 8 7 5 6 11 10 10.5 12 11 13 2 6 4 13.5 22

### Step 1: Enter the numbers in a list.

 Get into the Stats/List Editor. [`◆`] [`APPS`], select Stats/List Editor, and you should be on the list entry screen. Enter the data points. Cursor to the heading `list1` (not the first data line) and press [`CLEAR`] [`ENTER`] to clear the list.   Enter the x values. (The order doesn’t matter.)

### Step 2: Clear other plots.

 Disable any other plots and graphs that could overlay your box-whisker plot [`F2`] [`3`] turns off statistics plots, and [`F2`] [`4`] turns off graphs of equations.

### Step 3: Set up the boxplot.

 Get to the Plot Setup screen, and select a modified boxplot. (“Modified” means it shows outliers if there are any.) Press [`F2`] [`1`]. Then, cursor to an empty plot, or one you don’t care about keeping.   Press [`F1`] [`►`] [`5`]. Fill in the Define Plot screen. Use the [`ALPHA`] key to type `list1`: [`ALPHA` `4` makes `l`] [`ALPHA` `9` makes `i`] [`ALPHA` `3` makes `s`], then plain [`T`] [`1`] [`ENTER`] [`ENTER`].

### Step 4: Display the boxplot.

 On the box-whisker diagram, any outliers show as isolated squares. The whiskers are mix and max (disregarding any outliers), and the box is first quartile, median, and third quartile. Press [`F5`], which is ZoomData or “zoom to statistics data”. Identify the outliers, if any. Press [`F3`] to trace on the plot. Use [`◄`] and [`►`] to display the numbers in the five-number summary as well as any outliers. Here, you see that there is an outlier with a value of 22.

## What’s New?

• 7 Nov 2020: Convert page frm HTML 4.01 to HTML5, and italicize a variable name.
• 2 Feb 2015: New article.