How to find the predicted Y given a specific X value after regression

[Yao Zhao]

I know one method is that first I can write the regression equation by writing down the coefficients. Then I can use

display

to calculate manually.

But what's the smart methods? If I have a lot of Xs, above method looks silly.

[Igor Paploski]

help predict

[Yao Zhao]

predict is for all of Xs of all observations in the data. I only want to know, say, what's the Y given X=15. Maybe there is no X=15 in the sample.

[Bruce Weaver]

Look up -margins-. E.g.,

clear *
sysuse auto
summarize length
regress weight length
margins, at(length = (140 240)) vsquish
margins, at(length = (140(10)240)) vsquish