By Variable

Use this field to specify a BY variable from the Experimental Design SAS Data Set to use in your analysis. Separate analyses are conducted for distinct levels of the BY group variable.

BY Variables

BY variables are optional (in most processes) variable specifications whose values define groups of observations, such as hour, month, or year. BY variables can enable analyses to be performed separately on different groups as defined by that variable. Choosing a BY variable such as gender, for example, groups the subjects by gender and conducts two separate analyses: one for males and one for females.

Alternatively, specifying a BY variable enables you to animate an image so that you can see how response values change according to some grouping, like over time.

To Specify a BY Variable:

8      Specify the Experimental Design SAS Data Set.

All of the variables in the specified data set are displayed in the Available Variables field.

8      Examine the list of available variables.
8      Highlight the variables by which you want to groups your results.
8      Click to add the highlighted variable to the By Variable field.

Note: If no BY variables are specified, the analysis is conducted across all the subjects.