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ECOM II

detected, will take to you a screen that details the problem and allows you to remove

one of the correlated variables.

9.3

Backward Stepwise Linear Regression

Backward stepwise regression starts with all explanatory variables included the

model. It then removes the least significant explanatory variable, that is, the one with

the highest p value, at each step, until all variables have been added. By scrutinising

the overall fit of the model variables will be automatically removed until the optimum

model is found.

Load both your species and your environmental datasets as described in

Opening a data set

From the Regression menu on the Toolbar select Backward Stepwise. A list of

dependent variables (usually species) is displayed.

Select the species against which you wish to test your environmental variables.

Click OK to run the analysis and display the results on the Regression tab.

The results report shows the sequences of the procedure as Steps:

Copyright 2004  PISCES Conservation Ltd