Right now I am just trying to understand if X an Y are associated. Or to state it another way ( I think) are X and Y independent of each other. Which it looks like they are not. ... View more

@PaigeMiller , You are right in that I have not clearly stated the null hypothesis. So lets assume my null hypothesis is there is no relationship between X any Y with 95% confidence. I get the following results:     Observed Y       0 1 Total X 0 1,360,524 1,073,073  2,433,597 1  194 7 201   Total 1,360,718 1,073,080 2,433,798           Expected   Y       0 1   X 0 1,360,606 1,072,991 2,433,597 1 112 89 201     1,360,718 1,073,080 2,433,798   Chi-Square = 134.47 (P < .0001) Odds Ratio = 0.0457 (0.0215 - 0.0972)   I interpret this to mean I can reject the null hypothesis, meaning there is a relationship between X an Y. Further the odds ratio suggest a negative correlation between X an Y (this is a surprising result). If a subject is in program X then an outcome of Y (Y=1) is less likely.    Here are some more measures: Statistic Value ASE Gamma -0.9125 0.0322 Kendall's Tau-b -0.0074 0.0004 Stuart's Tau-c -0.0001 0.0000 Somers' D C|R -0.4061 0.0129 Somers' D R|C -0.0001 0.0000 Pearson Correlation -0.0074 0.0004 Spearman Correlation -0.0074 0.0004 Lambda Asymmetric C|R 0.0000 0.0000 Lambda Asymmetric R|C 0.0000 0.0000 Lambda Symmetric 0.0000 0.0000 Uncertainty Coefficient C|R 0.0001 0.0000 Uncertainty Coefficient R|C 0.0422 0.0038 Uncertainty Coefficient Symmetric 0.0001 0.0000 ... View more

Thanks @PaigeMiller and @PGStats  for the direction. I spent some time getting familiar with the chi-square test for independence and the odds ratio. I think both could be relevant for my sceanatio.   My understanding is the chi-square test for independence can reject (or not) my null hypothesis with a certain level of confidence. Whereas the odd ration can quantify the strength of the relationship between X and Y. I will try running both tests on my data. ... View more

Is this what you are trying to do?   proc sql; select case when <put logic here> then a.column_A else b.column_B end as new_column from table_A as a join table_B as b on <put join here>; quit; ... View more