Use this to make comparisons between predicted means from a linear or generalized linear regression.

## Available data

This lists data structures appropriate to the current input field. The contents will change as you move from one field to the next. You can double-click a name to copy it to the current input field or type it in.

## Comparison factor

Specifies the factor amongst whose levels the comparisons are to be calculated.

## Comparison matrix

Provides a space to provide a matrix to specify the comparisons to be calculated. Each row in the matrix represents a separate contrast, and the columns in the matrix correspond to the factor levels.

## Groups

Specifies a factor to indicate that the comparisons are to be made for each level of that factor, or you can set it to a list of factors to make the comparisons for every combination of the levels of those factors.

## Display

Specifies the output to be displayed.

Analysis of variance |
Displays an analysis of variance giving the sums of squares and so on for the comparisons. |

Contrasts |
Displays the contrasts. |

## Standard errors

Specifies the form in which standard errors will be displayed: as standard errors of the contrasts, standard errors of differences, or least-significant differences (LSDs). If required, more than one type of standard error can be printed. The significance level for LSDs can be specified as a percentage (default 5) in the accompanying field.

## See also

- RCOMPARISONS procedure