###Here are two vectors with equal length, one for each variable.
###The length of the vectors corresponds to the number of individuals, 
###with each entry indicating the level by a numeric coding. This data comes 
###from a clinical trial of the drug propranolol. the vector drug is coded 
###for control or propranolol status and the vector status is coded yes or 
###no whether the patient survived at least 28 days.

drug<-c("control","control","control","control","prop",
"control","prop","control","prop","control",
"prop","prop","control","prop","prop",
"control","control","prop","prop","prop",
"prop","control","prop","control","control",
"prop","control","control","control","control",
"control","control","prop","control","prop",
"control","prop","prop","prop","control",
"prop","control","prop","control","prop",
"control","prop","control","control","prop",
"prop","prop","control","prop","prop",
"prop","control","control","control","prop",
"prop","control","prop","control","prop",
"control","prop","control","prop","control",
"prop","control","prop","control","prop",
"control","prop","control","prop","control",
"prop","control","prop","control","prop",
"control","prop","control","control","prop",
"prop")
status<-c("yes","yes","yes","no","yes","yes","yes","yes","yes",
"yes","yes","no","no","yes","yes","no","no", "yes",
"yes","yes","yes","no","yes","yes","no","yes","no",
"yes","no","yes","no","yes","no","yes","yes","no",
"no","yes","yes","yes","yes","yes","yes","yes","yes",
"no","yes","no","yes","yes","yes","yes","yes","yes",
"yes","yes","yes","yes","yes","no","yes","yes","yes",
"no","no","no","yes","yes","yes","yes","no","no",
"yes","yes","yes","yes","yes","yes","yes","yes","yes",
"yes","yes","yes","yes","yes","yes","no","no","yes",
"no")