Keeping data in memory

[Laura Myles]

Dear Listers,

I have 2 small datasets in Stata. One contains some estimation parameters for different conditions: I have 4 possible scenario which corresponds to different ratios (based on assumptions); the ratios are calculated based on grouped data within the dataset

scenario lambda
A 0.2
B 0.4
C 0.6
D 0.8


I would then like to apply those estimated ratios (lambdas) to a a second dataset to estimate the number of observations based on each of the 4 scenarios to allocate the number of responses to be 20% vs. 80% in group 1 and 2, respectively under scenario A for example.

I am not sure I can easily merge the two datasets as they don't have a shared variable - is there any way I can call parameters from dataset one into dataset two or should I use local macros?

Thanks!

[Clyde Schechter]

-help cross- will create four observations for each observation originally in the second data set, one for each of the four scenarios.

That said, I think in some situations like this, with only four scenarios, I would just create local macros lambda_A, lambda_B, lambda_C, and lambda_D with the corresponding values and use those with the second data set.

Which approach is better would depend on exactly what you are going to be doing.