Two random samples of households, one of households who purchase Crest toothpaste and one of households who do not. For each household the age is recorded of the person responsible for purchasing the toothpaste.
两个随机样本的家庭,一个家庭购买佳洁士牙膏和一个家庭谁不。对于每个家庭购买牙膏的负责人的年龄记录。
用法----------Usage----------
data (toothpaste.df)
格式----------Format----------
A data frame with 20 observations on 2 variables.
2个变量的20个观测数据框。