Software:SPSS-PieCharts

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To make a pie chart in SPSS:
  • Choose the menu option $Graphs \rightarrow Legacy~Dialogs \rightarrow Pie$
Piecharts - SPSS.png
  • You want the default choice (Summaries for groups of cases), so just click [Define].
  • Move the categorical variable for which you want to make a pie-chart into the "Define slices by" box. For the NoClickQuery data, move over the variable Reason.
Piecharts 1 - SPSS.PNG
  • Click [OK].
The pie chart will look like this:
NoClickQuery-Pie-SPSS.png
How to Weight Cases
By default, SPSS assumes that you are analyzing survey data. That means, each row represents one individual. If you have data where counts have been summarized, the slices in the pie chart you just created will all have equal areas. (You will be able to recognize this situation because you will have one column that gives the data and another column giving a count of how many times each value occurred.)
Open the data file NoClickQuery-Summary. Notice that each row in this data file represents the responses of several individuals. The Count column tells how many times each response was given. The data in this file have been summarized.
Before creating a plot with summarized data, you need to weight the cases. This tells SPSS to look in the column of counts to determine how many times each value occurred.
To weight cases in SPSS, do the following:
  • Choose the menu option $Data \rightarrow Weight~cases\cdots$
Weight Cases - SPSS.png
  • Click on the radio button next to "Weight cases by".
  • Move the variable that gives the counts (i.e. Count) into the "Frequency variable" box.
Weight Cases 1 - SPSS.PNG
  • Click [OK].
Whenever you do any operation, SPSS will treat each row as if it is repeated the number of times indicated by the weighting variable. If you weight cases, be sure you do this before you make your graphs.
Your pie chart will have all the same information as the original chart, but it will include a statement indicating that the variable Count was used to give the weight or size of each slice of the pie.
NoClickQuerySummary-Hist-SPSS.png