#Việc 1 #Việc 2 Cài đặt các gói phân tích (packages) #Việc 3 Đọc dữ liệu vào R
ob=read.csv("C:\\Users\\DELL\\Downloads\\Obesity data.csv")#Việc 4 ##4.1 Có bao nhiêu biến số và quan sát
dim(ob)## [1] 1217 13##4.2 Liệt kê 6 quan sát đầu tiên
head(ob)## id gender height weight bmi age WBBMC wbbmd fat lean pcfat hypertension
## 1 1 F 150 49 21.8 53 1312 0.88 17802 28600 37.3 0
## 2 2 M 165 52 19.1 65 1309 0.84 8381 40229 16.8 1
## 3 3 F 157 57 23.1 64 1230 0.84 19221 36057 34.0 1
## 4 4 F 156 53 21.8 56 1171 0.80 17472 33094 33.8 1
## 5 5 M 160 51 19.9 54 1681 0.98 7336 40621 14.8 0
## 6 6 F 153 47 20.1 52 1358 0.91 14904 30068 32.2 1
## diabetes
## 1 1
## 2 0
## 3 0
## 4 0
## 5 0
## 6 0##4.3 Liệt kê 6 quan sát cuối cùng
tail(ob)## id gender height weight bmi age WBBMC wbbmd fat lean pcfat
## 1212 1222 F 153 50 21.4 59 1309 0.87 18328 29147 37.6
## 1213 1223 F 150 44 19.6 44 1474 0.95 12906 28534 30.1
## 1214 1224 F 148 51 23.3 58 1522 0.97 14938 33931 29.6
## 1215 1225 F 149 50 22.5 57 1409 0.93 16777 30598 34.4
## 1216 1226 F 144 49 23.6 67 1266 0.90 20094 27272 41.3
## 1217 1227 F 141 45 22.6 58 1228 0.91 14567 28111 33.2
## hypertension diabetes
## 1212 1 0
## 1213 0 1
## 1214 0 0
## 1215 1 0
## 1216 1 0
## 1217 0 0##4.4 Tóm tắt
summary(ob)## id gender height weight
## Min. : 1.0 Length:1217 Min. :136.0 Min. :34.00
## 1st Qu.: 309.0 Class :character 1st Qu.:151.0 1st Qu.:49.00
## Median : 615.0 Mode :character Median :155.0 Median :54.00
## Mean : 614.5 Mean :156.7 Mean :55.14
## 3rd Qu.: 921.0 3rd Qu.:162.0 3rd Qu.:61.00
## Max. :1227.0 Max. :185.0 Max. :95.00
## bmi age WBBMC wbbmd fat
## Min. :14.5 Min. :13.00 Min. : 695 Min. :0.650 Min. : 4277
## 1st Qu.:20.2 1st Qu.:35.00 1st Qu.:1481 1st Qu.:0.930 1st Qu.:13768
## Median :22.2 Median :48.00 Median :1707 Median :1.010 Median :16955
## Mean :22.4 Mean :47.15 Mean :1725 Mean :1.009 Mean :17288
## 3rd Qu.:24.3 3rd Qu.:58.00 3rd Qu.:1945 3rd Qu.:1.090 3rd Qu.:20325
## Max. :37.1 Max. :88.00 Max. :3040 Max. :1.350 Max. :40825
## lean pcfat hypertension diabetes
## Min. :19136 Min. : 9.2 Min. :0.000 Min. :0.0000
## 1st Qu.:30325 1st Qu.:27.0 1st Qu.:0.000 1st Qu.:0.0000
## Median :33577 Median :32.4 Median :1.000 Median :0.0000
## Mean :35463 Mean :31.6 Mean :0.507 Mean :0.1109
## 3rd Qu.:39761 3rd Qu.:36.8 3rd Qu.:1.000 3rd Qu.:0.0000
## Max. :63059 Max. :48.4 Max. :1.000 Max. :1.0000#Việc 5 Biên tập dữ liệu ##5.1 Mã hóa biến gender
ob$sex[ob$gender == "M"] = 0
ob$sex[ob$gender == "F"] = 1
head(ob)## id gender height weight bmi age WBBMC wbbmd fat lean pcfat hypertension
## 1 1 F 150 49 21.8 53 1312 0.88 17802 28600 37.3 0
## 2 2 M 165 52 19.1 65 1309 0.84 8381 40229 16.8 1
## 3 3 F 157 57 23.1 64 1230 0.84 19221 36057 34.0 1
## 4 4 F 156 53 21.8 56 1171 0.80 17472 33094 33.8 1
## 5 5 M 160 51 19.9 54 1681 0.98 7336 40621 14.8 0
## 6 6 F 153 47 20.1 52 1358 0.91 14904 30068 32.2 1
## diabetes sex
## 1 1 1
## 2 0 0
## 3 0 1
## 4 0 1
## 5 0 0
## 6 0 1table(ob$sex, ob$gender)##
## F M
## 0 0 355
## 1 862 0ob$sex.b = ifelse(ob$gender== "F", 1, 0)
table(ob$sex.b, ob$gender)##
## F M
## 0 0 355
## 1 862 0##5.2 Mã hóa biến BMI
ob$obese[ob$bmi<18.5] = "Thieu can"
ob$obese[ob$bmi>18.5 & ob$bmi < 25] = "Binh thuong"
ob$obese[ob$bmi>=25 & ob$bmi < 30] = "Thua can"
ob$obese[ob$bmi>=30] = "Beo phi"
head(ob)## id gender height weight bmi age WBBMC wbbmd fat lean pcfat hypertension
## 1 1 F 150 49 21.8 53 1312 0.88 17802 28600 37.3 0
## 2 2 M 165 52 19.1 65 1309 0.84 8381 40229 16.8 1
## 3 3 F 157 57 23.1 64 1230 0.84 19221 36057 34.0 1
## 4 4 F 156 53 21.8 56 1171 0.80 17472 33094 33.8 1
## 5 5 M 160 51 19.9 54 1681 0.98 7336 40621 14.8 0
## 6 6 F 153 47 20.1 52 1358 0.91 14904 30068 32.2 1
## diabetes sex sex.b obese
## 1 1 1 1 Binh thuong
## 2 0 0 0 Binh thuong
## 3 0 1 1 Binh thuong
## 4 0 1 1 Binh thuong
## 5 0 0 0 Binh thuong
## 6 0 1 1 Binh thuong##5.3 Tạo biến số mới
ob$lean.kg = ob$lean/1000
ob$fat.kg = ob$fat/1000##5.4 Tạo tập dữ liệu ‘men.overweight’
men.overweight = subset(ob, gender == "M" & bmi >= 25)
dim(ob)## [1] 1217 18dim(men.overweight)## [1] 85 18table(men.overweight$obese)##
## Beo phi Thua can
## 4 81head(men.overweight)## id gender height weight bmi age WBBMC wbbmd fat lean pcfat hypertension
## 16 16 M 150 70 31.1 49 2084 1.00 16540 49512 24.3 1
## 18 18 M 158 65 26.0 49 2557 1.29 11716 45567 19.6 1
## 19 19 M 162 72 27.4 66 1535 0.86 25416 44577 35.5 1
## 26 26 M 172 78 26.4 52 1991 0.95 19772 55200 25.7 0
## 40 40 M 171 75 25.6 51 2192 1.13 18188 51801 25.2 1
## 69 69 M 168 80 28.3 53 2043 1.06 17907 54594 24.0 0
## diabetes sex sex.b obese lean.kg fat.kg
## 16 0 0 0 Beo phi 49.512 16.540
## 18 0 0 0 Thua can 45.567 11.716
## 19 0 0 0 Thua can 44.577 25.416
## 26 0 0 0 Thua can 55.200 19.772
## 40 0 0 0 Thua can 51.801 18.188
## 69 0 0 0 Thua can 54.594 17.907##5.5 Tạo tập dữ liệu ‘Demo’
demo = subset(ob, select = c(id, gender, weight, height, pcfat))
dim(demo)## [1] 1217 5head(demo)## id gender weight height pcfat
## 1 1 F 49 150 37.3
## 2 2 M 52 165 16.8
## 3 3 F 57 157 34.0
## 4 4 F 53 156 33.8
## 5 5 M 51 160 14.8
## 6 6 F 47 153 32.2