Texas Instruments TINSPIRECX manual Dragging on the Charts, Working with Frequency Data

It is also possible to arrange side-by-side comparisons of corresponding summary statistics for two or more data sets and this makes drawing inferences from the statistics very quick and very clear. The best way to do this is to select more than one list above.

Dragging on the Charts

An interesting feature is the ability to drag plotted points around charts, thus changing the original data. Go back to the page on which you created the scatterplot for male hand spans and shoe sizes. You left the plot showing the y=mx+b regression line and equation.

First Steps with TI-Nspire™

Tutorial 7: One- and two-variable statistics

Sets of statistics

Move the cursor to a point very near the line of best fit. The cursor changes to a hand with a finger pointing upwards when it is pointing to a data point. Click and hold x.

Move the cursor to investigate the effect that moving this point has on the regression line. Below, the point has been moved to the top of the screen for maximum effect.

The effect of moving a point from here … … to here.

This shows the effect of changing a single hand-span value from 21cm to 32cm

Working with Frequency Data

In the previous tutorial we entered some grouped data for shoe sizes. We will now explore some of the ways we can work with that data using TI-Nspire. Start by returning to the Lists & Spreadsheet page we created in the previous tutorial.

We can use the same process we used above to find summary statistics for this frequency data.

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