[R] mean of a column in a list of data frames

[Brandon Payne]

I have a list of data frames,

    ownersList <- list(exp2004owners,exp2005owners,
                   exp2006owners,exp2007owners,
                   exp2008owners,exp2009owners,
                   exp2010owners,exp2011owners,
                   exp2012owners,exp2013owners,
                   exp2014owners)

 I want to take the mean of the first column $grossIncome.
 I can access the first column with

lapply(ownersList, "[[", 1)                      ##works

But I can't take the mean of that.
mean(lapply(ownersList, "[[", 1))          ##not working

There must be a more idiomatic way to write this with map or apply.

ownersIncome<- c(mean(ownersList[[1]]$grossIncome),
                 mean(ownersList[[2]]$grossIncome),
                 mean(ownersList[[3]]$grossIncome),
                 mean(ownersList[[4]]$grossIncome),
                 mean(ownersList[[5]]$grossIncome),
                 mean(ownersList[[6]]$grossIncome),
                 mean(ownersList[[7]]$grossIncome),
                 mean(ownersList[[8]]$grossIncome),
                 mean(ownersList[[9]]$grossIncome),
                 mean(ownersList[[10]]$grossIncome),
                 mean(ownersList[[11]]$grossIncome))

I tried a for loop, which also didn't work.

aList<-
    for(i in 1:3){
    mean(ownersList[[i]]$grossIncome)
}
aList

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