# Population abundance inference

I have the following data (R code):

rm(list=ls())
sampleA<-c(20,30,NA,50,50,30,10,NA)
sampleB<-c(NA,30,40,50,NA,60,20,30)
par(mfrow=c(1,2))
plot(sampleA,xlim=c(0,11),ylim=c(0,60))
plot(sampleB,xlim=c(0,11),ylim=c(0,60))


Is there a way I can infer the NA values with a given degree of confidence?

Not sure how helpful this is with a small sample size but you could infer the NA values with a median call:

median(na.omit(sampleA))
[1] 30


To set NAs to medians you would do something akin to this:

sampleA[is.na(sampleA)] <- median(na.omit(sampleA))
sampleA
[1] 20 30 30 50 50 30 10 30


If you have any other grouping for each sample you could grouped median/means for each of the NA values that belong to a particular group.

• Thank you for the answer. I do not think that swapping NA values for the mean or median is appropiate for my data. I was thinking about obtaining the probability density distribution and follow/interpolate in the curve or something like that. Not sure if that is correct though. – Charly Nov 27 '17 at 12:48