Number of smokers in a case-control study.
data(Smoking_DollHill1950)
The format is: table [1:6, 1:2, 1:2] 2 33 250 196 136 32 27 55 293 190 ... - attr(*, "dimnames")=List of 3 ..$ Smoking : chr [1:6] "Nonsmoker" "1-" "5-" "15-" ... ..$ Diagnosis: chr [1:2] "Lung cancer" "Other" ..$ Sex : chr [1:2] "Male" "Female"
This is Table V from Doll and Hill (1950).
Richard Doll (1998), Uncovering the effects of smoking: historical perspective. Statistical Methods in Medical Research, 7(87), 87-117