Bubble charts

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From the Plots menu, Bubble charts show measures and fit values graphically. They are featured in Bond & Fox. For successful operation, Excel must be available on your computer. Its maximum is 65,536 rows.

 

To produce these charts, Winsteps writes out the requisite values into a temporary file. Excel is then launched automatically. It reads in the temporary file and follows instructions to create a bubble plot. The plot is displayed, and the Excel worksheet becomes available for any alterations that are desired. The Excel worksheet may be made permanent using "Save As".

 

Selecting "Bubble Chart" from the Plots menu:

 

boption

 

Here is the vertical-measure bubble-plot for the KCT data as it appears on your computer screen. Bubbles are sized by their standard errors.

 

buv

 

Or when it is formatted for printing portrait-orientation on legal-size paper, using Excel printer set-up:

 

buvp

 

And the horizontal-measure bubble-plot for the KCT data as it appears on your computer screen:

 

buh

 

 


Bubble Resizing: The relative bubble sizes are set by the standard errors of the measures. But their overall standard size is set by Excel. To change their overall sizes, right click on the edge of a circle. Then use Excel's "Format Data Series", "Options", "Scale bubble size to:"

 

rebubble


Help for WINSTEPS® Rasch Measurement Software: www.winsteps.com.