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rtidyversecontingency

Contingency table when you have a column with count values

I have a dataframe that looks something like this:

Year      Var    Count
2019       A     10
2020       B     23
2019       B     36
2020       A     42

How can I make a Year x Var contingency table using the "Count" column as frequencies?

Solution

  • We can use xtabs in base R

    xtabs(Count ~ Year + Var, df1)
#        Var
#Year    A  B
#   2019 10 36
#   2020 42 23

    To include the row/column totals, can use addmargins

    addmargins(xtabs(Count ~ Year + Var, df1))
#     Var
#Year     A   B Sum
#  2019  10  36  46
#  2020  42  23  65
#  Sum   52  59 111

    data

    df1 <- structure(list(Year = c(2019L, 2020L, 2019L, 2020L), Var = c("A", 
"B", "B", "A"), Count = c(10L, 23L, 36L, 42L)), class = "data.frame",
row.names = c(NA, 
-4L))