How to use R for multiple select questions?

Question

I am trying to figure out how to analyze multiple select/multiple responses (i.e., \'select all that apply\') questions in a survey I recently conducted.

SPSS has nice c

Answer 1

multfreqtable(data_set, "Banner")
multfreqtable = function(data, question.prefix) {
  z = length(question.prefix)
  temp = vector("list", z)

  for (i in 1:z) {
    a = grep(question.prefix[i], names(data))
    b = sum(data[, a] != 0)
    d = colSums(data[, a] != 0)
    e = sum(rowSums(data[,a]) !=0)
    f = as.numeric(c(d, b))
    temp[[i]] = data.frame(question = c(sub(question.prefix[i], 
                                            "", names(d)), "Total"),
                           freq = f,
                           percent_response = (f/b)*100,
                           percent_cases = (f/e)*100 )
    names(temp)[i] = question.prefix[i]
  }
  temp
}

does a very good job of giving you numbers, percentages at the number of cases level and percentage at the number of responses level. Perfect for analyzing Multi-Response Questions