topic Re: Sign of Predictors in Regression Model in Statistical Procedures

Sign of Predictors in Regression Model

vishal_prof_gmail_com — Sun, 15 May 2016 05:22:56 GMT

Hi,

In Regression Model , it is possible that a predictor may have positive relation with dependent variable in Bi-variate analysis , however in Model Equation the predictor may have a negative sign. Why this happens and how is this resolved.

This can happen in Trainin & Validation data as well. That is a predictor may have a Positive sign in the Model equation in Training data set and negative sign in Validation Data-set.

Re: Sign of Predictors in Regression Model

Norman21 — Sun, 15 May 2016 06:51:36 GMT

To me, this indicates a problem somewhere, either in selection of the model, or partitioning of the data into training and validation sets.

Do you have an example that you can post?

Re: Sign of Predictors in Regression Model

Reeza — Sun, 15 May 2016 08:58:11 GMT

Simpsons Paradox

http://stats.stackexchange.com/questions/1580/regression-coefficients-that-flip-sign-after-including-other-predictors