set.seed(123)

# Jumlah responden
n <- 30

# Generate data kesehatan
aktivitas_fisik <- sample(1:7, n, replace = TRUE)   # jam olahraga per minggu
bmi             <- rnorm(n, mean = 24, sd = 3)      # indeks massa tubuh
tekanan_darah   <- 110 + 2 * bmi - 3 * aktivitas_fisik + rnorm(n, 0, 5)

# Membuat data frame
data_kesehatan <- data.frame(
  aktivitas_fisik,
  bmi,
  tekanan_darah
)

data_kesehatan

##    aktivitas_fisik      bmi tekanan_darah
## 1                7 25.49355      137.9727
## 2                7 18.10015      122.8670
## 3                3 26.10407      157.1080
## 4                6 22.58163      136.7464
## 5                3 20.79653      143.8597
## 6                2 23.34608      150.5494
## 7                2 20.92199      145.6296
## 8                6 21.81333      142.4697
## 9                3 22.12488      144.1209
## 10               5 18.93992      140.4622
## 11               4 26.51336      143.2830
## 12               6 24.46012      143.8433
## 13               6 20.58559      133.7904
## 14               1 27.76144      163.6026
## 15               2 25.27939      156.4570
## 16               3 23.11479      144.7180
## 17               5 26.68538      146.7047
## 18               3 26.63440      149.1759
## 19               3 26.46474      148.5705
## 20               1 26.06592      160.6495
## 21               4 25.66175      151.5646
## 22               1 23.81426      154.8936
## 23               1 23.08211      157.7756
## 24               5 22.85859      150.9676
## 25               3 21.91588      142.3766
## 26               2 23.37625      139.2067
## 27               7 20.20381      134.4363
## 28               2 30.50687      161.4677
## 29               1 27.62389      158.8077
## 30               6 20.63067      138.3892

summary(data_kesehatan)

##  aktivitas_fisik      bmi        tekanan_darah  
##  Min.   :1.000   Min.   :18.10   Min.   :122.9  
##  1st Qu.:2.000   1st Qu.:21.84   1st Qu.:140.9  
##  Median :3.000   Median :23.36   Median :145.2  
##  Mean   :3.667   Mean   :23.78   Mean   :146.7  
##  3rd Qu.:5.750   3rd Qu.:26.09   3rd Qu.:154.1  
##  Max.   :7.000   Max.   :30.51   Max.   :163.6

sd(data_kesehatan$aktivitas_fisik)

## [1] 2.022858

sd(data_kesehatan$bmi)

## [1] 2.914163

sd(data_kesehatan$tekanan_darah)

## [1] 9.478107

plot(data_kesehatan$aktivitas_fisik,
     data_kesehatan$tekanan_darah,
     main = "Scatter Plot Aktivitas Fisik vs Tekanan Darah",
     xlab = "Aktivitas Fisik (jam/minggu)",
     ylab = "Tekanan Darah Sistolik",
     pch = 19)

abline(lm(tekanan_darah ~ aktivitas_fisik, data = data_kesehatan),
       lwd = 2)

# korelasi pearson

cor.test(data_kesehatan$aktivitas_fisik,
         data_kesehatan$tekanan_darah,
         method = "pearson")

## 
##  Pearson's product-moment correlation
## 
## data:  data_kesehatan$aktivitas_fisik and data_kesehatan$tekanan_darah
## t = -6.9254, df = 28, p-value = 1.578e-07
## alternative hypothesis: true correlation is not equal to 0
## 95 percent confidence interval:
##  -0.8978435 -0.6085362
## sample estimates:
##        cor 
## -0.7945998

#korelasi spearman

cor.test(data_kesehatan$aktivitas_fisik,
         data_kesehatan$tekanan_darah,
         method = "spearman")

## Warning in cor.test.default(data_kesehatan$aktivitas_fisik,
## data_kesehatan$tekanan_darah, : Cannot compute exact p-value with ties

## 
##  Spearman's rank correlation rho
## 
## data:  data_kesehatan$aktivitas_fisik and data_kesehatan$tekanan_darah
## S = 8081.2, p-value = 1.292e-07
## alternative hypothesis: true rho is not equal to 0
## sample estimates:
##        rho 
## -0.7978233

#Korelasi Kendall

cor.test(data_kesehatan$aktivitas_fisik,
         data_kesehatan$tekanan_darah,
         method = "kendall")

## Warning in cor.test.default(data_kesehatan$aktivitas_fisik,
## data_kesehatan$tekanan_darah, : Cannot compute exact p-value with ties

## 
##  Kendall's rank correlation tau
## 
## data:  data_kesehatan$aktivitas_fisik and data_kesehatan$tekanan_darah
## z = -4.7708, p-value = 1.835e-06
## alternative hypothesis: true tau is not equal to 0
## sample estimates:
##        tau 
## -0.6494421