Parallel Slope Test Using Indicator Variables

PARALLEL SLOPE TEST USING INDICATOR VARIABLES 

If the slopes are parallel, this is the same thing as saying X3 = X1X2 = 0 that is, there is no significant interaction between Xi and X2. The model, y = ho + hiXi + biXi + Z 3X3, can be used to determine interaction between multiple products. Using the previous example and the six-step procedure, 

Step 3 Specify the test statistic. We will use the partial F test.  

Regression Analysis with Interaction Term, Example 9.1  

Analysis of Variance Source Regression Error Total 

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PARALLEL SLOPE TEST USING INDICATOR VARIABLES... 

The test for parallel slopes also can be easily performed using indicator variables. Using the same model again,... 

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