question about update()

Adelchi Azzalini · 2023-05-04T08:34:00Z

> On 4 May 2023, at 10:26, Duncan Murdoch wrote: > > On 04/05/2023 4:05 a.m., Adelchi Azzalini via R-help wrote: >> Hi. There must be something about the use of update() which I do not grasp, >> as the next exercise indicates. >> Suppose that obj is an object returned by a call to lm() or glm(). >> Next, a new variable xf is constructed using the same dataframe used >> for producing obj. Then >> obj$data > new.obj <- update(obj, . ~ . + x

Adelchi Azzalini

Thu, May 4, 2023 1:34 AM

Thanks, Duncan. What you indicate is surely the ideal route. Unfortunately, in my case this is not feasible, because the construction of xf and the update call are within an iterative procedure where xf is changed at each iteration, so that the steps 

obj$data <- cbind(obj$data, xf=xf)
new.obj <- update(obj, . ~ . + xf)
 
must be repeated hundreds of times, each with a different xf.

Adelchi

Thread (4 messages)

Adelchi Azzalini question about update() May 4 Duncan Murdoch question about update() May 4 Berwin A Turlach question about update() May 4 Adelchi Azzalini question about update() May 4