Question

I got a bunch dynamically created regressions stored in some list called regressions. Now I´d like to rename their coefficients efficiently. What I have so far is this loop that works:

for (i in 1:length(params[,1])){
names(regressions[[i]]$coefficients)[pos] <- paste(params[i,1],".lag",params[i,2],sep="")
}

I’ve been trying for quite a while to get this done a little more generally with the help of a function, cause this not the only list of regressions I have. However I could not get anything else to work. Here a few other tries basically based on lapply:

 correctNames <- function(reglist,namevec,pos){
 names(reglist[[i]]$coefficients)[pos] <- as.character(namevec)
}

lapply(regressions,correctNames(reglist,namevec,pos),
reglist=regressions,namevec=params[,1],pos=2)

Another try was to write a function with a for loop which also works internally as print shows but does not assign the names globally (where the regressions list is stored).

correctNames <- function(reglist,pos,namevec){
for (i in 1:length(params[,1])){
names(reglist[[i]]$coefficients)[pos] <- paste(namevec,".lag",namevec,sep="")
}
#this test proves it's work inside the function... 
print(reglist[[10]]
}

Ah, gimme a break.

Answer 1

There’s no “i” inside that first version of “correctNames” function; and you probably don’t realize that you are not assigning it to “regressions”, only to a copy of the regression object. Try instead:

correctNames <- function(reglist,namevec,pos){
  names(reglist$coefficients)[pos] <- as.character(namevec)
   return(reglist)                          }
newregs <- mapply(correctNames,  
                     reglist=regressions, 
                     namevec=as.character(params[,1]), 
                     MoreArgs= list( pos=2))

After seeing the note from Ramnath and noticing that the code did work but was giving flaky names for the “params” I looked at params and saw that it was a factor, and so changed the argument in the mapply call to as.character(params[,1]).

> newregs[1,1]
[[1]]
(Intercept)     log(M1) 
  -5.753758    2.178137