On Dec 3, 2013, at 12:45 PM, Juan Manuel Reyes S wrote: > Dear R-project > > I could not validate one logistic model because when I used the function > lrm.fit of the package rms the program showed a error message. It said that > the variable Clam and offset must have same length.
Giving arguments of the same length to a regression function would certainly seem to be appropriate. > > ext <- lrm.fit( ,Clam, offset="X") "X" would be a one-element character vector. Cannot tell what the object `Clam` might be. I certainly hope you have not been using the `attach` function. That way lies madness. The three first arguments to `lrm.fit` are: x: design matrix with no column for an intercept y: response vector, numeric, categorical, or character offset: optional numeric vector containing an offset on the logit scale > > In this case, Clam is variable depend or variable that we want to > predictive and X is linear predictor of the other logistic model. Other model? > > We want to evaluate a logistic model in new data set. Evaluate? Please explain in more detail what procedure you propose. The `validate` function in pkg:rms would need a fit object that has been created with x=TRUE and y=TRUE. > However, we don't > have the development data set of logistic model, only we have the equation. > We are using the function lrm.fit because it allows to use offset. `lrm` does allow an offset by way of its formula argument. See Arguments section of ?lrm > > What do you recommend me? > I recommend that you give a more complete example of your data, your "model", and your code that presents what you actually do have in hand. -- David. > Thank you member of R-project > > Juan Manuel Reyes > > [[alternative HTML version deleted]] > > David Winsemius Alameda, CA, USA ______________________________________________ R-help@r-project.org mailing list https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide http://www.R-project.org/posting-guide.html and provide commented, minimal, self-contained, reproducible code.
