forecast.lm() and NEWDATA
On Nov 1, 2013, at 6:50 AM, Ryan wrote:
Good day all. I am hoping you can help me (and I did this right). I've been working in R for a week now, and have encountered a problem with forecast.lm(). I have a list of 12 variables, all type = double, with 15 data entries. (I imported them from tab delimited text files, and then formatted as.numeric to change from list to double) (I understand that this leaves me rather limited in my degrees of freedom, but working with what I have, sadly. ) I have a LM model, such that REGGY = lm(formula=Y~A,B,C,...,I,J)
This looks wrong. Separating independent predictors with commas would be highly unusual.
which I am happy with. I have NEWDATA = data.frame(A+B+C+D....+I+J)
This also looks wrong. Separating arguments to data.frame with "+"-signs is surely wrong.
When i try to run forecast.lm(REGGY, h=5) i receive the following error "Error in as.data.frame(newdata) : argument "newdata" is missing, with no default"
If your code prior to calling forecast on the REGGY-object was really what you showed here, I am not surprised. You should post the output of str() on the data-objects that has the 12 variables and if it was modified the data argument pasted to `lm()` when you made REGGY. (Beginners should name their data arguments.)
When I run forecast.lm(REGGY, NEWDATA, h=5) I receive the confidence intervals of the 15 data entries I already possess. I understand that by including NEWDATA, the "h=5" is ignored, but without NEWDATA, I receive the error message. Can anyone help me please? Regards Ryan P.S The forecast is trying to predict the next 5 values for Y from the regression model pasted above. I'm a bit rusty with regressions, but I think I've covered my bases as well as I can, and from what I understand of the R code, I'm following the right steps.
Not if what you posted here was your code. I think you missed a few crucials points about R syntax.
David Winsemius Alameda, CA, USA