# Pooling regression results in SPSS

I have to solve the following issue:

1. I run my linear regression model many times (let's say 1000 times) with two variables: y - continuous dependent variable, x - continuous independent variable (mean of several consequent measurements).
2. The independent variable in each model was randomly drawn using its mean and standard deviation
3. I have the regression coefficient and standard error for this independent variable in each of the models.

Somehow I have to combine these results into one regression result. As far as I know the regression coefficients of 1000 models can be just averaged. However, this is not really clear to me how can I estimate the total variance of 1000 models.

• I'm curious - how, mechanically, would you go about combining the 1000 sets of results using spss? – rolando2 Oct 10 '13 at 16:29

• Hi abc, it would be good to expand this answer, as links go bad. A simple note and/or reference about Rubin's rules for combining models should suffice. The SPSS docs give Li, K. H., T. E. Raghunathan, and D. B. Rubin. 1991. Large-Sample Significance Levels from Multiply Imputed Data Using Moment-Based Statistics and an F Reference Distribution. Journal of the American Statistical Association, 86, 1065-1073. and Schafer, J. L. 1997. Analysis of Incomplete Multivariate Data. London: Chapman and Hall. as references for the multiple imputation algorithm. – Andy W Oct 9 '13 at 12:50