미국 의료비

insurance = read.csv('mlwr/insurance.csv') # 데이터 확인str(insurance)'data.frame': 1338 obs. of 7 variables:$ age : int 19 18 28 33 32 31 46 37 37 60 ...$ sex : Factor w/ 2 levels "female","male": 1 2 2 2 2 1 1 1 2 1 ...$ bmi : num 27.9 33.8 33 22.7 28.9 25.7 33.4 27.7 29.8 25.8 ...$ children: int 0 1 3 0 0 0 1 3 2 0 ...$ smoker : Factor w/ 2 levels "no","yes": 2 1 1 1 1 1 1 1 1 1 ...$ region : Fact..