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xniu86
07-11-2006, 11:47 AM
Dear subscribers:

Question: How to compare several regression slopes obtained on the same subjects
at variuous conditions ?

In the experiments we recorded outcome variables (digit forces) at different
levels of factors A, B and C. Factor A is quantitative, factors B and C are
qualitative (not measurable). We computed linear regressions of the forces on
factor A at various combinations of factors C and D. Visually, some regression
slopes look similar while others look different. If it were not regression
slopes but other variables, e.g. forces, we would apply for the data analysis
a repeated measure two-way ANOVA with factors B and C as inputs.

What is a proper way for analyzing the regression slopes? Is it correct to use
a two-way ANOVA or the repeated measure two-way ANOVA to analyze the effects of
factors B and C on the regression slopes? Note that the regression slopes
(regression coefficients) are not additive.


Your answers will be posted


Xun

Penn State Univ., UP