Texas Instruments TINSPIRECX manual Comparing Boxplots, Charts for Categorical Data

First Steps with TI-Nspire™

Tutorial 7: One- and two-variable statistics

Display the boxplot and then move the cursor over the chart. You will be able to see the median, quartiles, maximum and minimum values and, possibly, outlier values.

Upper quartile displayed

Comparing Boxplots
This boxplot can be compared with a similar one representing
the female shoe sizes by displaying them, one above another.
To do this we add a second X Variable by pressing b24,
this will give you the choice of available lists.
This time select fshoe. The result is two side by side box plots
that can easily be compared.
This method can be used to add more box plots, up to five or
six can be easily compared on the same screen.	Comparing shoe sizes

Charts for Categorical Data

Create a new Data & Statistics page and choose the variable mshoe for the x axis.

This variable contains a list of numerical data but they could also be thought of as categorical data, in which case it would be appropriate to use a Pie Chart. By using the option Force Categorical X in the Plot Properties menu you can force the handheld to treat the data in this way. Notice the way in which the labels on the axis change.

A Pie Chart displaying categorical data

Now you can use the Plot Type menu to choose Pie Chart.

It is also possible to enter non-numerical categorical data in a Lists & Spreadsheet page, e.g., favourite pets, sandwich fillings etc. Such data must be entered in quotation marks by pressing /r(Ó).

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