Generalized additive model data.frame.default error: attempting to apply nonfunction

Question

I am trying to run a general additive model using the mgcv package, but I keep getting a model.frame.default error:

Error in model.frame.default(formula = Prese         


        

Answer 1

The problem is this

na.action = TRUE

na.action requires a function and you passed it a logical, (from ?bam)

na.action: a function which indicates what should happen when the data contain NAs. The default is set by the na.action setting of options, and is na.fail if that is unset. The factory-fresh default is na.omit.

Essentially, within model.frame() you were basically asking R to evaluate

TRUE(df)

which rightly throws an error as TRUE isn't a function yet was being called as one.

If you want to omit rows with NAs rather than fail if they occur, use

na.action = na.omit