I repeat here the illustrative correlation matrix (N = 150) that I used in the Study Suggestions for Chapters 8 and 9.
Using a computer program, regress verbal achievement on the five independent variables.
(a) What is R2?
(b) What is the regression equation?
(c) What information would you need to convert the ß's obtained in (b) to b's?
(d) Assuming you were to use magnitude of the Ws as indices of the effects of the variables with which they are associated, interpret the results.
(e) The validity of the preceding interpretation is predicated, among other things, on the assumptions that the model is correctly specified and that the measures of the independent variables are perfectly reliable. Discuss the implications of this statement.
(f) Using relevant information from the computer output, what is 1 –
, where
is the squared multiple correlation of each independent variable with the remaining independent variables. What is this value called? How is it used in computer programs for regression analysis?
(g) What is 1/(1 -
) for each of the independent variables? What is it called? What is it used for?