# numerical rules
age >= 0
height > 0
age <= 150
age > yearsmarried

# categorical rules
status %in% c("married","single","widowed")
agegroup %in% c("child","adult","elderly")
if ( status == "married" ) agegroup %in% c("adult","elderly")

# mixed rules
if ( status %in% c("married","widowed")) age - yearsmarried >= 17
if ( age < 18 ) agegroup == "child"
if ( age >= 18 && age <65 ) agegroup == "adult"
if ( age >= 65 ) agegroup == "elderly"