topic Re: Get proc SQL to produce 95% confidence interval in SAS Procedures

Get proc SQL to produce 95% confidence interval

elopomorph — Tue, 09 Sep 2014 18:41:52 GMT

I created SAS code using proc SQL to calculate a weighted mean by year. My SAS code is below. My weight variable is called bwght and I weight the variable called CPUE for each year. This code produces the weighted mean by year and calls it bwghtedAverage. However, I can't figure out how I an get proc sql to also provide me with the 95% confidence intervals for this mean. Any help would be greatly appreciated.

proc sql;

title 'Weighted Averages';

select Year, sum(CPUE*bwght)/sum(bwght) as bwghtedAverage

from (select Year, CPUE,

case

when bwght gt 0 then bwght

else 0

end as bwght

from CPUEdat)

group by Year /*major_area_code*/;

quit;

Re: Get proc SQL to produce 95% confidence interval

Reeza — Tue, 09 Sep 2014 18:43:44 GMT

You'd have to do the manual calculations using the formula. Why not use proc means instead?

Re: Get proc SQL to produce 95% confidence interval

elopomorph — Tue, 09 Sep 2014 18:53:32 GMT

I don't know how to do a weighted average in proc means. Can you provide an example?

Re: Get proc SQL to produce 95% confidence interval

Reeza — Tue, 09 Sep 2014 19:18:21 GMT

Here's a good example of how and looking at the vardef option as well.

Base SAS(R) 9.2 Procedures Guide

You'll still need to deal with the 0 or negative weights somehow before the proc.

Re: Get proc SQL to produce 95% confidence interval

Ksharp — Wed, 10 Sep 2014 12:48:45 GMT

And don't forget proc univariate