Multiple Regression and Betas
Message posted by Suzanne on November 5, 1999 at 12:00 AM (ET)

I have three variables that I am analyzing: Predictor A, Predictor B, and a dependent variable. I am predicting that A and B both will be correlated with each other and with the dependent variable. I am also predicting that when I regress A and B simultaneously on my dependent variable, A will drop to nonsignificance, whereas B will remain significant. In other words, I am predicting that B will mediate the relationship between A and the dependent variable. In fact, this is what my data shows.

My question: When I looked at my standardized coefficients (betas) for A and B in the multiple regression, they BOTH were lower than they were for their respective bivariate regressions. What causes this drop in beta for both variables?

READERS RESPOND:
(In chronological order. Most recent at the bottom.)

Re: Multiple Regression and Betas
Message posted by JG on November 5, 1999 at 12:00 AM (ET)

Do stepwise regression . First regress on A and then regress the residuals on B, and then reverse the process. See what you get. Also calculate directly the correlation between A and B .

Re: Multiple Regression and Betas
Message posted by JG on November 5, 1999 at 12:00 AM (ET)

Re: Multiple Regression and Betas
Message posted by j-bamdad on November 5, 1999 at 12:00 AM (ET)

Re: Multiple Regression and Betas
Message posted by link@wild.com on March 2, 2000 at 12:00 AM (ET)