Applying glm coefficients (Beginner Question)

Thanks for the reply! Using predict() on new data works just fine. What I'm
interested in is, if I can use the coefficients or other data, to develop my
own formula which does the same as predict().

Of course you can. Extract the coefficients, apply them to the new data, and build predictions. The code is all there to see how it's done by the Masters. Perhaps you need to do a bit of reading. Or do some searching. There must be many worked examples of constructing logistic regression estimates from first principles on various faculty websites aroune th world. The Posting Guide requests that you not consider this list an elementary statistics tutoring service.

David Winsemius, MD
Alameda, CA, USA