Using apply over two lists of different lengths - r

Question

This question is related to my earlier question found here: https://stackoverflow.com/questions/33089532/r-accounting-for-a-factor-with-this-logistic-regression-function-replace-lappl
I realize that I didn't do a good job at asking the first question, so here is a more simple analog with actual data:
My data looks something like this:
#data look like this, but with a variable number of "y" columms
wk<-rep(1:50,2)
X<-rnorm(1:100,1)
y1<-rnorm(1:100,1)
y2<-rnorm(1:100,1)
df1<-as.data.frame(cbind(wk,X,y1,y2))
df1$hyst<-ifelse(df1$wk>=5 & df1$wk<32, "R", "F")
Y<-df1[, -which(colnames(df1) %in% c("wk"))] #this step makes more sense with my actual data since I have a bunch of columns to remove
l1<-length(Y)-1
lst1<-lapply(2:l1,function(x){colnames(Y[x])})
dflst<-c("Y",'Y[Y$hyst=="R",]','Y[Y$hyst=="F",]')
I want to run a model over all Y columns for the full data set (all data) and for two subsets, when the factor hyst=="R" and when hyst=="F".
To do this, I have nested two lapply functions, which sort of works, but I think it essentially doubles my results and is causing me all sorts of list headaches.
Here is the nested lapply code:
lms <- lapply(dflst, function(z){
lapply(lst1, function(y) {
form <- paste0(y, " ~ X")
lm(form, data=eval(parse(text=z)))
})
})
How can I replace or modify the nested lapply function to obtain a model run for each Y column for each data set( all, "R", and "F")?

Answer 1

Construct your DF list like
DFlst <- c(list(full=Y), split(Y, Y$hyst))
str(DFlst)
List of 3
$ full:'data.frame': 100 obs. of 4 variables:
..$ X : num [1:100] 1.792 3.192 0.367 1.632 1.388 ...
..$ y1 : num [1:100] 3.354 1.189 1.99 0.639 0.1 ...
..$ y2 : num [1:100] 0.864 2.415 0.437 1.069 1.368 ...
..$ hyst: chr [1:100] "F" "F" "F" "F" ...
$ F :'data.frame': 46 obs. of 4 variables:
..$ X : num [1:46] 1.792 3.192 0.367 1.632 0.707 ...
..$ y1 : num [1:46] 3.354 1.189 1.99 0.639 0.894 ...
..$ y2 : num [1:46] 0.864 2.415 0.437 1.069 1.213 ...
..$ hyst: chr [1:46] "F" "F" "F" "F" ...
$ R :'data.frame': 54 obs. of 4 variables:
..$ X : num [1:54] 1.388 2.296 0.409 1.494 0.943 ...
..$ y1 : num [1:54] 0.1002 0.6425 -0.0918 1.199 0.8767 ...
..$ y2 : num [1:54] 1.368 1.122 0.402 -0.237 1.518 ...
..$ hyst: chr [1:54] "R" "R" "R" "R" ...
Do some regressions:
res <- lapply(DFlst, function(DF) {
cols = grep("^y[0-9]+$",names(DF),value=TRUE)
lapply(setNames(cols,cols),
function(y) lm(paste(y,"~X"), data=DF))
})
str(res, list.len=2, give.attr=FALSE)
List of 3
$ full:List of 2
..$ y1:List of 12
.. ..$ coefficients : Named num [1:2] 0.903 0.111
.. ..$ residuals : Named num [1:100] 2.2509 -0.0698 1.046 -0.4464 -0.9578 ...
.. .. [list output truncated]
..$ y2:List of 12
.. ..$ coefficients : Named num [1:2] 1.423 -0.166
.. ..$ residuals : Named num [1:100] -0.2623 1.5213 -0.9253 -0.0837 0.1751 ...
.. .. [list output truncated]
$ F :List of 2
..$ y1:List of 12
.. ..$ coefficients : Named num [1:2] 0.9289 0.0769
.. ..$ residuals : Named num [1:46] 2.2871 0.0146 1.0332 -0.4157 -0.0889 ...
.. .. [list output truncated]
..$ y2:List of 12
.. ..$ coefficients : Named num [1:2] 1.4177 -0.0789
.. ..$ residuals : Named num [1:46] -0.413 1.25 -0.952 -0.22 -0.149 ...
.. .. [list output truncated]
[list output truncated]