Before fitting the regression model, you can transform factors. The most common type of transformation is an orthogonal transformation. The transformation is based on the range of values for the factor, such that the transformed value ranges from -1 to 1. In some instances, a transformation may also be applied on the response.

For example, if a factor, F1, has values ranging from 80 to 120, the transformed factor, say, TF1, has a range of -1 to 1.

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