R中的聚合 - na.omit和na.pass与因子（逐个因子）？

Question

I have a data set containing salaries test data. Not all cells have values hence I used na.action=na.pass,na.rm=TRUE but it gives me an error due to the fact that I want to aggregate with JobTitle which is factor?

So far I have developed below code:

aggregate(salaries$JobTitle, 
list(pay = salaries$TotalPay),
FUN=mean,
na.action=na.pass,
na.rm=TRUE)

My test data has the following columns:

'data.frame':   104 obs. of  36 variables:
 $ Id              : int  1 2 3 4 5 6 7 8 9 10 ...
 $ EmployeeName    : Factor w/ 11 levels "","ALBERT PARDINI",..: 10 7 2 4 11 6 3 5 9 8 ...
 $ JobTitle        : Factor w/ 9 levels "","ASSISTANT DEPUTY CHIEF II",..: 8 4 4 9 6 2 3 7 3 5 ...
 $ BasePay         : num  167411 155966 212739 77916 134402 ...
 $ OvertimePay     : num  0 245132 106088 56121 9737 ...
 $ OtherPay        : num  400184 137811 16453 198307 182235 ...
 $ Benefits        : logi  NA NA NA NA NA NA ...
 $ TotalPay        : num  567595 538909 335280 332344 326373 ...
 $ TotalPayBenefits: num  567595 538909 335280 332344 326373 ...
 $ Year            : int  2011 2011 2011 2011 2011 2011 2011 2011 2011 2011 ...
 $ Notes           : logi  NA NA NA NA NA NA ...
 $ Agency          : Factor w/ 2 levels "","San Francisco": 2 2 2 2 2 2 2 2 2 2 ..

The error code which comes up is

Warning messages:
1: In mean.default(X[[i]], ...) :
  argument is not numeric or logical: returning NA
2: In mean.default(X[[i]], ...) :
  argument is not numeric or logical: returning NA

etc...

I have tried with salaries$Id and it work like magic so I assume the code is correct and perhaps I need to change the data type for JobTitle?

Answer 1

If we are getting the mean of 'TotalPay grouped by 'JobTitle', the formula` method would be

aggregate(TotalPay~JobTitle, salaries, mean, na.rm=TRUE, na.action=na.pass)

Or use

aggregate(salaries$TotalPay, list(salaries$JobTitle), FUN=mean, na.rm=TRUE) 

data

set.seed(24)
salaries <- data.frame(JobTitle = sample(LETTERS[1:5], 20,
       replace=TRUE), TotalPay= sample(c(1:20, NA), 20))