RMSLE looping in R

Question

I have a dataframe consisting of observed and modelled data that I am trying to do a RMSLE metric on. The data is stored in one text file, which I can read in and has the format similar to this:

Group	Time	Observed	Predicted
A	2	190	312
A	3	174	345
A	6	150	290
A	12	85	217
B	4	300	725
B	9	113	426
B	13	120	393
B	23	97	263

question from:https://stackoverflow.com/questions/65877489/rmsle-looping-in-r

Answer 1

You are using the unsplitted full data.frame to assign your y_pred and y_true. You should assign y_pred and y_true inside the for loop using the splitted data.frame.

#Now get statistic for each Group using a for loop
res <- list()
for (n in names (spp.l)){
   dat <- spp.l[[n]]
   y_true = dat$Observed
   y_pred = dat$Predicted
   RMSLE = RMSLE(y_pred = y_pred, y_true = y_true)
   res[[n]] <- data.frame(
      Group=n,
      RMSLE,
      n.samples=nrow(dat)
   )
}