1. Persiapan Data
# Load Library
library(psych)
library(corrplot)
## corrplot 0.95 loaded
library(FactoMineR)
library(factoextra)
## Loading required package: ggplot2
##
## Attaching package: 'ggplot2'
## The following objects are masked from 'package:psych':
##
## %+%, alpha
## Welcome to factoextra!
## Want to learn more? See two factoextra-related books at https://www.datanovia.com/en/product/practical-guide-to-principal-component-methods-in-r/
library(GPArotation)
##
## Attaching package: 'GPArotation'
## The following objects are masked from 'package:psych':
##
## equamax, varimin
library(ggplot2)
library(tidyr)
library(dplyr)
##
## Attaching package: 'dplyr'
## The following objects are masked from 'package:stats':
##
## filter, lag
## The following objects are masked from 'package:base':
##
## intersect, setdiff, setequal, union
library(Hmisc)
##
## Attaching package: 'Hmisc'
## The following objects are masked from 'package:dplyr':
##
## src, summarize
## The following object is masked from 'package:psych':
##
## describe
## The following objects are masked from 'package:base':
##
## format.pval, units
library(sjPlot)
##
## Attaching package: 'sjPlot'
## The following object is masked from 'package:ggplot2':
##
## set_theme
library(openxlsx)
# Import Dataset
data <- read.csv('D:/KULIYEAH/Semester 4/Analisis Multivariat/Dataset_Updated.csv')
cat("Dimensi data:", dim(data), "\n")
## Dimensi data: 1205 12
# Ambil variabel numerik
data_num <- data[, sapply(data, is.numeric)]
# Cek Struktur
str(data_num)
## 'data.frame': 1205 obs. of 11 variables:
## $ Age : int 22 22 27 20 20 22 20 23 22 26 ...
## $ Systolic.BP : int 90 110 110 100 90 120 110 110 90 110 ...
## $ Diastolic : int 60 70 70 70 60 70 70 80 60 70 ...
## $ BS : num 9 7.1 7.5 7.2 7.5 7.01 9 7 6.4 12 ...
## $ Body.Temp : int 100 98 98 98 98 98 102 98 98 100 ...
## $ BMI : num 18 20.4 23 21.2 19.7 24 17.6 21.3 22 30.2 ...
## $ Previous.Complications: int 1 0 1 0 0 0 0 0 0 1 ...
## $ Preexisting.Diabetes : int 1 0 0 0 0 0 1 0 0 1 ...
## $ Gestational.Diabetes : int 0 0 0 0 0 0 0 0 0 1 ...
## $ Mental.Health : int 1 0 0 0 0 0 0 0 0 1 ...
## $ Heart.Rate : int 80 74 72 74 74 76 78 74 72 80 ...
# Statistik Deskriptif
summary(data_num)
## Age Systolic.BP Diastolic BS
## Min. : 10.00 Min. : 70.0 Min. : 40.00 Min. : 3.000
## 1st Qu.: 21.00 1st Qu.:100.0 1st Qu.: 65.00 1st Qu.: 6.000
## Median : 25.00 Median :120.0 Median : 80.00 Median : 6.900
## Mean : 27.73 Mean :116.8 Mean : 77.17 Mean : 7.501
## 3rd Qu.: 32.00 3rd Qu.:130.0 3rd Qu.: 90.00 3rd Qu.: 7.900
## Max. :325.00 Max. :200.0 Max. :140.00 Max. :19.000
## NA's :5 NA's :4 NA's :2
## Body.Temp BMI Previous.Complications Preexisting.Diabetes
## Min. : 97.0 Min. : 0.00 Min. :0.0000 Min. :0.0000
## 1st Qu.: 98.0 1st Qu.:20.45 1st Qu.:0.0000 1st Qu.:0.0000
## Median : 98.0 Median :23.00 Median :0.0000 Median :0.0000
## Mean : 98.4 Mean :23.32 Mean :0.1754 Mean :0.2884
## 3rd Qu.: 98.0 3rd Qu.:25.00 3rd Qu.:0.0000 3rd Qu.:1.0000
## Max. :103.0 Max. :37.00 Max. :1.0000 Max. :1.0000
## NA's :18 NA's :2 NA's :2
## Gestational.Diabetes Mental.Health Heart.Rate
## Min. :0.0000 Min. :0.0000 Min. :58.00
## 1st Qu.:0.0000 1st Qu.:0.0000 1st Qu.:70.00
## Median :0.0000 Median :0.0000 Median :76.00
## Mean :0.1178 Mean :0.3344 Mean :75.82
## 3rd Qu.:0.0000 3rd Qu.:1.0000 3rd Qu.:80.00
## Max. :1.0000 Max. :1.0000 Max. :92.00
## NA's :2
describe(data_num)
## data_num
##
## 11 Variables 1205 Observations
## --------------------------------------------------------------------------------
## Age
## n missing distinct Info Mean pMedian Gmd .05
## 1205 0 43 0.998 27.73 26.5 10.19 17
## .10 .25 .50 .75 .90 .95
## 18 21 25 32 39 48
##
## lowest : 10 12 13 15 16, highest: 55 60 63 65 325
## --------------------------------------------------------------------------------
## Systolic.BP
## n missing distinct Info Mean pMedian Gmd .05
## 1200 5 24 0.964 116.8 115 20.67 90
## .10 .25 .50 .75 .90 .95
## 90 100 120 130 140 140
##
## lowest : 70 75 76 78 80, highest: 150 160 170 180 200
## --------------------------------------------------------------------------------
## Diastolic
## n missing distinct Info Mean pMedian Gmd .05
## 1201 4 21 0.975 77.17 76.5 16.07 60
## .10 .25 .50 .75 .90 .95
## 60 65 80 90 100 100
##
## lowest : 40 45 49 50 55, highest: 100 110 120 130 140
## --------------------------------------------------------------------------------
## BS
## n missing distinct Info Mean pMedian Gmd .05
## 1203 2 84 0.998 7.501 6.95 3.061 3.9
## .10 .25 .50 .75 .90 .95
## 4.1 6.0 6.9 7.9 11.0 15.0
##
## lowest : 3 3.01 3.3 3.4 3.5 , highest: 15 16 17 18 19
## --------------------------------------------------------------------------------
## Body.Temp
## n missing distinct Info Mean pMedian Gmd
## 1205 0 7 0.375 98.4 98 0.7403
##
## Value 97 98 99 100 101 102 103
## Frequency 12 1030 7 41 66 43 6
## Proportion 0.010 0.855 0.006 0.034 0.055 0.036 0.005
## --------------------------------------------------------------------------------
## BMI
## n missing distinct Info Mean pMedian Gmd .05
## 1187 18 157 0.998 23.32 23 4.282 18.00
## .10 .25 .50 .75 .90 .95
## 18.90 20.45 23.00 25.00 29.00 30.27
##
## lowest : 0 15 15.5 15.6 15.9, highest: 34.5 35 35.1 36 37
## --------------------------------------------------------------------------------
## Previous.Complications
## n missing distinct Info Sum Mean
## 1203 2 2 0.434 211 0.1754
##
## --------------------------------------------------------------------------------
## Preexisting.Diabetes
## n missing distinct Info Sum Mean
## 1203 2 2 0.616 347 0.2884
##
## --------------------------------------------------------------------------------
## Gestational.Diabetes
## n missing distinct Info Sum Mean
## 1205 0 2 0.312 142 0.1178
##
## --------------------------------------------------------------------------------
## Mental.Health
## n missing distinct Info Sum Mean
## 1205 0 2 0.668 403 0.3344
##
## --------------------------------------------------------------------------------
## Heart.Rate
## n missing distinct Info Mean pMedian Gmd .05
## 1203 2 31 0.99 75.82 75 8.032 66
## .10 .25 .50 .75 .90 .95
## 70 70 76 80 88 90
##
## lowest : 58 60 62 64 65, highest: 87 88 89 90 92
## --------------------------------------------------------------------------------
# Cek Missing Value
colSums(is.na(data_num))
## Age Systolic.BP Diastolic
## 0 5 4
## BS Body.Temp BMI
## 2 0 18
## Previous.Complications Preexisting.Diabetes Gestational.Diabetes
## 2 2 0
## Mental.Health Heart.Rate
## 0 2
# Handling Missing Value
data_num1 <- data.frame(lapply(data_num, function(x) {
x[is.na(x)] <- median(x, na.rm = TRUE)
return(x)
}))
# Cek Missing Value Setelah Handling
colSums(is.na(data_num1))
## Age Systolic.BP Diastolic
## 0 0 0
## BS Body.Temp BMI
## 0 0 0
## Previous.Complications Preexisting.Diabetes Gestational.Diabetes
## 0 0 0
## Mental.Health Heart.Rate
## 0 0
summary(data_num1)
## Age Systolic.BP Diastolic BS
## Min. : 10.00 Min. : 70.0 Min. : 40.00 Min. : 3.0
## 1st Qu.: 21.00 1st Qu.:100.0 1st Qu.: 65.00 1st Qu.: 6.0
## Median : 25.00 Median :120.0 Median : 80.00 Median : 6.9
## Mean : 27.73 Mean :116.8 Mean : 77.18 Mean : 7.5
## 3rd Qu.: 32.00 3rd Qu.:130.0 3rd Qu.: 90.00 3rd Qu.: 7.9
## Max. :325.00 Max. :200.0 Max. :140.00 Max. :19.0
## Body.Temp BMI Previous.Complications Preexisting.Diabetes
## Min. : 97.0 Min. : 0.00 Min. :0.0000 Min. :0.000
## 1st Qu.: 98.0 1st Qu.:21.00 1st Qu.:0.0000 1st Qu.:0.000
## Median : 98.0 Median :23.00 Median :0.0000 Median :0.000
## Mean : 98.4 Mean :23.31 Mean :0.1751 Mean :0.288
## 3rd Qu.: 98.0 3rd Qu.:25.00 3rd Qu.:0.0000 3rd Qu.:1.000
## Max. :103.0 Max. :37.00 Max. :1.0000 Max. :1.000
## Gestational.Diabetes Mental.Health Heart.Rate
## Min. :0.0000 Min. :0.0000 Min. :58.00
## 1st Qu.:0.0000 1st Qu.:0.0000 1st Qu.:70.00
## Median :0.0000 Median :0.0000 Median :76.00
## Mean :0.1178 Mean :0.3344 Mean :75.82
## 3rd Qu.:0.0000 3rd Qu.:1.0000 3rd Qu.:80.00
## Max. :1.0000 Max. :1.0000 Max. :92.00
describe(data_num1)
## data_num1
##
## 11 Variables 1205 Observations
## --------------------------------------------------------------------------------
## Age
## n missing distinct Info Mean pMedian Gmd .05
## 1205 0 43 0.998 27.73 26.5 10.19 17
## .10 .25 .50 .75 .90 .95
## 18 21 25 32 39 48
##
## lowest : 10 12 13 15 16, highest: 55 60 63 65 325
## --------------------------------------------------------------------------------
## Systolic.BP
## n missing distinct Info Mean pMedian Gmd .05
## 1205 0 24 0.964 116.8 115 20.62 90
## .10 .25 .50 .75 .90 .95
## 90 100 120 130 140 140
##
## lowest : 70 75 76 78 80, highest: 150 160 170 180 200
## --------------------------------------------------------------------------------
## Diastolic
## n missing distinct Info Mean pMedian Gmd .05
## 1205 0 21 0.975 77.18 76.5 16.04 60
## .10 .25 .50 .75 .90 .95
## 60 65 80 90 100 100
##
## lowest : 40 45 49 50 55, highest: 100 110 120 130 140
## --------------------------------------------------------------------------------
## BS
## n missing distinct Info Mean pMedian Gmd .05
## 1205 0 84 0.998 7.5 6.95 3.057 3.9
## .10 .25 .50 .75 .90 .95
## 4.1 6.0 6.9 7.9 11.0 15.0
##
## lowest : 3 3.01 3.3 3.4 3.5 , highest: 15 16 17 18 19
## --------------------------------------------------------------------------------
## Body.Temp
## n missing distinct Info Mean pMedian Gmd
## 1205 0 7 0.375 98.4 98 0.7403
##
## Value 97 98 99 100 101 102 103
## Frequency 12 1030 7 41 66 43 6
## Proportion 0.010 0.855 0.006 0.034 0.055 0.036 0.005
## --------------------------------------------------------------------------------
## BMI
## n missing distinct Info Mean pMedian Gmd .05
## 1205 0 157 0.997 23.31 23 4.243 18.00
## .10 .25 .50 .75 .90 .95
## 18.90 21.00 23.00 25.00 28.96 30.20
##
## lowest : 0 15 15.5 15.6 15.9, highest: 34.5 35 35.1 36 37
## --------------------------------------------------------------------------------
## Previous.Complications
## n missing distinct Info Sum Mean
## 1205 0 2 0.433 211 0.1751
##
## --------------------------------------------------------------------------------
## Preexisting.Diabetes
## n missing distinct Info Sum Mean
## 1205 0 2 0.615 347 0.288
##
## --------------------------------------------------------------------------------
## Gestational.Diabetes
## n missing distinct Info Sum Mean
## 1205 0 2 0.312 142 0.1178
##
## --------------------------------------------------------------------------------
## Mental.Health
## n missing distinct Info Sum Mean
## 1205 0 2 0.668 403 0.3344
##
## --------------------------------------------------------------------------------
## Heart.Rate
## n missing distinct Info Mean pMedian Gmd .05
## 1205 0 31 0.99 75.82 75 8.025 66
## .10 .25 .50 .75 .90 .95
## 70 70 76 80 88 90
##
## lowest : 58 60 62 64 65, highest: 87 88 89 90 92
## --------------------------------------------------------------------------------
desc <- describe(data_num1)
# Simpan dalam Bentuk Tabel
desc_table <- data.frame(
Variable = rownames(desc),
Mean = round(as.numeric(desc$mean), 3),
Median = round(as.numeric(desc$median), 3),
SD = round(as.numeric(desc$sd), 3),
Min = as.numeric(desc$min),
Max = as.numeric(desc$max)
)
write.xlsx(desc_table, "tabel_deskriptif.xlsx", rowNames = FALSE)
# Plot Distribusi Tiap Variabel
data_long <- stack(data_num1)
ggplot(data_long, aes(x = values)) +
geom_histogram(bins = 30, fill = "skyblue", color = "black") +
facet_wrap(~ ind, scales = "free") +
theme_minimal()

data_long <- data_num1 %>%
pivot_longer(cols = everything(),
names_to = "Variable",
values_to = "Value")
ggplot(data_long, aes(x = Variable, y = Value)) +
geom_boxplot(fill = "#69b3a2", alpha = 0.7) +
theme_minimal(base_size = 12) +
theme(axis.text.x = element_text(angle = 45, hjust = 1)) +
labs(title = "Boxplot Seluruh Variabel Numerik",
x = "Variabel",
y = "Nilai")

# Standarisasi Skala
data_scaled <- scale(data_num1)
data_scaled_long <- as.data.frame(data_scaled) %>%
pivot_longer(cols = everything(),
names_to = "Variable",
values_to = "Value")
ggplot(data_scaled_long, aes(x = Variable, y = Value)) +
geom_boxplot(fill = "#E69F00", alpha = 0.7) +
theme_minimal(base_size = 12) +
theme(axis.text.x = element_text(angle = 45, hjust = 1)) +
labs(title = "Boxplot Setelah Standarisasi",
y = "Z-Score")

3. Principal Component Analysis (PCA)
3a. Total Variance Explained
# 1. PCA tanpa rotasi
pca_result <- prcomp(data_num1, scale. = TRUE)
# Eigenvalue
eigenvalues <- pca_result$sdev^2
# Proporsi Varians
prop_var <- eigenvalues / sum(eigenvalues)
# Kumulatif Varians
cum_var <- cumsum(prop_var)
# Buat tabel Total Variance Explained
total_variance <- data.frame(
Component = 1:length(eigenvalues),
Eigenvalue = eigenvalues,
Proportion_Variance = prop_var,
Cumulative_Variance = cum_var
)
round(total_variance, 4)
## Component Eigenvalue Proportion_Variance Cumulative_Variance
## 1 1 3.4778 0.3162 0.3162
## 2 2 1.6141 0.1467 0.4629
## 3 3 1.2551 0.1141 0.5770
## 4 4 0.9735 0.0885 0.6655
## 5 5 0.8201 0.0746 0.7401
## 6 6 0.7345 0.0668 0.8068
## 7 7 0.6005 0.0546 0.8614
## 8 8 0.5484 0.0499 0.9113
## 9 9 0.4517 0.0411 0.9523
## 10 10 0.3227 0.0293 0.9817
## 11 11 0.2016 0.0183 1.0000
total_variance$Proportion_Variance <- total_variance$Proportion_Variance * 100
total_variance$Cumulative_Variance <- total_variance$Cumulative_Variance * 100
round(total_variance, 2)
## Component Eigenvalue Proportion_Variance Cumulative_Variance
## 1 1 3.48 31.62 31.62
## 2 2 1.61 14.67 46.29
## 3 3 1.26 11.41 57.70
## 4 4 0.97 8.85 66.55
## 5 5 0.82 7.46 74.01
## 6 6 0.73 6.68 80.68
## 7 7 0.60 5.46 86.14
## 8 8 0.55 4.99 91.13
## 9 9 0.45 4.11 95.23
## 10 10 0.32 2.93 98.17
## 11 11 0.20 1.83 100.00
# 2. PCA
pca_result <- prcomp(data_num1, scale. = TRUE)
# Hitung eigenvalue
eigenvalues <- pca_result$sdev^2
# Hitung persen varians
percent_var <- eigenvalues / sum(eigenvalues) * 100
# Hitung kumulatif
cumulative_var <- cumsum(percent_var)
# Buat tabel seperti SPSS
total_variance <- data.frame(
Komponen = 1:length(eigenvalues),
Total = round(eigenvalues, 2),
`Persen Varians` = round(percent_var, 2),
`Kumulatif %` = round(cumulative_var, 2)
)
total_variance
## Komponen Total Persen.Varians Kumulatif..
## 1 1 3.48 31.62 31.62
## 2 2 1.61 14.67 46.29
## 3 3 1.26 11.41 57.70
## 4 4 0.97 8.85 66.55
## 5 5 0.82 7.46 74.01
## 6 6 0.73 6.68 80.68
## 7 7 0.60 5.46 86.14
## 8 8 0.55 4.99 91.13
## 9 9 0.45 4.11 95.23
## 10 10 0.32 2.93 98.17
## 11 11 0.20 1.83 100.00
3b. Scree Plot
# Hitung eigenvalue
eigenvalues <- pca_result$sdev^2
plot(eigenvalues,
type = "b",
pch = 19,
xlab = "Komponen",
ylab = "Eigenvalue",
main = "Scree Plot PCA",
ylim = c(0, max(eigenvalues)))
abline(h = 1, col = "red", lty = 2, lwd = 2)

3c. Communalities
# Tentukan jumlah komponen (eigenvalue > 1)
eigenvalues <- pca_result$sdev^2
k <- sum(eigenvalues > 1)
# Jalankan PCA lagi dengan k komponen
pca_k <- prcomp(data_num1, scale. = TRUE)
# Ambil loading
loadings <- pca_k$rotation[, 1:k]
# Hitung communalities (jumlah kuadrat loading)
communalities <- rowSums(loadings^2)
# Buat tabel
communalities_table <- data.frame(
Variabel = rownames(loadings),
Initial = 1,
Extraction = round(communalities, 3)
)
communalities_table
## Variabel Initial Extraction
## Age Age 1 0.312
## Systolic.BP Systolic.BP 1 0.423
## Diastolic Diastolic 1 0.397
## BS BS 1 0.251
## Body.Temp Body.Temp 1 0.259
## BMI BMI 1 0.132
## Previous.Complications Previous.Complications 1 0.178
## Preexisting.Diabetes Preexisting.Diabetes 1 0.272
## Gestational.Diabetes Gestational.Diabetes 1 0.457
## Mental.Health Mental.Health 1 0.194
## Heart.Rate Heart.Rate 1 0.124
# Tentukan jumlah komponen
eigenvalues <- pca_result$sdev^2
k <- sum(eigenvalues > 1)
# Jalankan PCA dengan psych agar lebih mudah
library(psych)
pca_psych <- principal(data_num1, nfactors = k, rotate = "none")
# Ambil communalities (Extraction)
communalities <- pca_psych$communality
# Buat tabel seperti di gambar
comm_table <- data.frame(
Variabel = names(communalities),
Extraction = round(communalities, 6)
)
comm_table
## Variabel Extraction
## Age Age 0.493461
## Systolic.BP Systolic.BP 0.838861
## Diastolic Diastolic 0.809065
## BS BS 0.713695
## Body.Temp Body.Temp 0.406529
## BMI BMI 0.446322
## Previous.Complications Previous.Complications 0.500155
## Preexisting.Diabetes Preexisting.Diabetes 0.616487
## Gestational.Diabetes Gestational.Diabetes 0.650558
## Mental.Health Mental.Health 0.529467
## Heart.Rate Heart.Rate 0.342479
3d. Pengelompokan faktor-faktor utama
# Tentukan jumlah komponen (misal eigenvalue > 1)
ev <- eigen(cor(data_num1))$values
k <- sum(ev > 1)
# Jalankan PCA dengan rotasi varimax
pca_rot <- principal(data_num1,
nfactors = k,
rotate = "varimax",
scores = TRUE)
# Lihat hasil loading
print(pca_rot$loadings)
##
## Loadings:
## RC1 RC2 RC3
## Age 0.301 0.179 -0.609
## Systolic.BP 0.149 0.904
## Diastolic 0.191 0.879
## BS 0.731 0.280 -0.318
## Body.Temp 0.317 -0.384 0.398
## BMI 0.580 0.326
## Previous.Complications 0.702
## Preexisting.Diabetes 0.716 -0.321
## Gestational.Diabetes 0.287 0.236 0.716
## Mental.Health 0.705 0.168
## Heart.Rate 0.569 0.124
##
## RC1 RC2 RC3
## SS loadings 3.029 2.018 1.300
## Proportion Var 0.275 0.183 0.118
## Cumulative Var 0.275 0.459 0.577
loadings_matrix <- as.data.frame(unclass(pca_rot$loadings))
round(loadings_matrix, 3)
## RC1 RC2 RC3
## Age 0.301 0.179 -0.609
## Systolic.BP 0.149 0.904 -0.017
## Diastolic 0.191 0.879 0.009
## BS 0.731 0.280 -0.318
## Body.Temp 0.317 -0.384 0.398
## BMI 0.580 0.326 0.058
## Previous.Complications 0.702 0.043 0.075
## Preexisting.Diabetes 0.716 0.002 -0.321
## Gestational.Diabetes 0.287 0.236 0.716
## Mental.Health 0.705 0.065 0.168
## Heart.Rate 0.569 0.053 0.124
# Ambil loading absolut terbesar tiap variabel
grouping <- apply(abs(loadings_matrix), 1, which.max)
# Buat tabel pengelompokan
hasil_kelompok <- data.frame(
Variabel = rownames(loadings_matrix),
Komponen_Dominan = paste0("Komponen ", grouping)
)
hasil_kelompok
## Variabel Komponen_Dominan
## 1 Age Komponen 3
## 2 Systolic.BP Komponen 2
## 3 Diastolic Komponen 2
## 4 BS Komponen 1
## 5 Body.Temp Komponen 3
## 6 BMI Komponen 1
## 7 Previous.Complications Komponen 1
## 8 Preexisting.Diabetes Komponen 1
## 9 Gestational.Diabetes Komponen 3
## 10 Mental.Health Komponen 1
## 11 Heart.Rate Komponen 1
# Ambil rotated loadings
loadings_matrix <- as.data.frame(unclass(pca_rot$loadings))
# Bulatkan
loadings_matrix <- round(loadings_matrix, 3)
# Ganti nama kolom sesuai jumlah komponen
colnames(loadings_matrix) <- paste0("Komponen ", 1:ncol(loadings_matrix))
# Tambahkan nama variabel sebagai kolom
loadings_matrix$Variabel <- rownames(loadings_matrix)
# Pindahkan kolom Variabel ke depan
loadings_matrix <- loadings_matrix[, c("Variabel", paste0("Komponen ", 1:ncol(pca_rot$loadings)))]
loadings_matrix
## Variabel Komponen 1 Komponen 2 Komponen 3
## Age Age 0.301 0.179 -0.609
## Systolic.BP Systolic.BP 0.149 0.904 -0.017
## Diastolic Diastolic 0.191 0.879 0.009
## BS BS 0.731 0.280 -0.318
## Body.Temp Body.Temp 0.317 -0.384 0.398
## BMI BMI 0.580 0.326 0.058
## Previous.Complications Previous.Complications 0.702 0.043 0.075
## Preexisting.Diabetes Preexisting.Diabetes 0.716 0.002 -0.321
## Gestational.Diabetes Gestational.Diabetes 0.287 0.236 0.716
## Mental.Health Mental.Health 0.705 0.065 0.168
## Heart.Rate Heart.Rate 0.569 0.053 0.124
dominant <- apply(abs(loadings_matrix[, -1]), 1, which.max)
loadings_matrix$Dominan <- paste0("Komponen ", dominant)
loadings_matrix
## Variabel Komponen 1 Komponen 2 Komponen 3
## Age Age 0.301 0.179 -0.609
## Systolic.BP Systolic.BP 0.149 0.904 -0.017
## Diastolic Diastolic 0.191 0.879 0.009
## BS BS 0.731 0.280 -0.318
## Body.Temp Body.Temp 0.317 -0.384 0.398
## BMI BMI 0.580 0.326 0.058
## Previous.Complications Previous.Complications 0.702 0.043 0.075
## Preexisting.Diabetes Preexisting.Diabetes 0.716 0.002 -0.321
## Gestational.Diabetes Gestational.Diabetes 0.287 0.236 0.716
## Mental.Health Mental.Health 0.705 0.065 0.168
## Heart.Rate Heart.Rate 0.569 0.053 0.124
## Dominan
## Age Komponen 3
## Systolic.BP Komponen 2
## Diastolic Komponen 2
## BS Komponen 1
## Body.Temp Komponen 3
## BMI Komponen 1
## Previous.Complications Komponen 1
## Preexisting.Diabetes Komponen 1
## Gestational.Diabetes Komponen 3
## Mental.Health Komponen 1
## Heart.Rate Komponen 1
4. Factor Analysis (FA)
4a. Estimasi Faktor Matriks
# 1. Hitung Eigen Value
df2 <- data_scaled
cor_matrix <- cor(df2)
eigen_result <- eigen(cor_matrix)
eigenvalues <- eigen_result$values
print(eigenvalues)
## [1] 3.4778297 1.6141165 1.2551309 0.9734905 0.8200721 0.7344577 0.6005218
## [8] 0.5484470 0.4516542 0.3226874 0.2015922
eigen <- data.frame(
Eigenvalue = round(eigenvalues, 3),
Proporsi_Var = round(eigenvalues / sum(eigenvalues) * 100, 2),
Kumulatif = round(cumsum(eigenvalues / sum(eigenvalues)) * 100, 2)
)
print(eigen)
## Eigenvalue Proporsi_Var Kumulatif
## 1 3.478 31.62 31.62
## 2 1.614 14.67 46.29
## 3 1.255 11.41 57.70
## 4 0.973 8.85 66.55
## 5 0.820 7.46 74.01
## 6 0.734 6.68 80.68
## 7 0.601 5.46 86.14
## 8 0.548 4.99 91.13
## 9 0.452 4.11 95.23
## 10 0.323 2.93 98.17
## 11 0.202 1.83 100.00
# 2. FA tanpa rotasi
n_factors <- sum(eigenvalues > 1)
fa_unrotated <- fa(df2,
nfactors = n_factors,
rotate = "none",
fm = "pa",
use = "complete.obs")
print(fa_unrotated$loadings, cutoff = 0.1)
##
## Loadings:
## PA1 PA2 PA3
## Age 0.320 -0.318
## Systolic.BP 0.628 -0.699
## Diastolic 0.611 -0.561
## BS 0.775 0.161 -0.294
## Body.Temp 0.301 0.184
## BMI 0.575
## Previous.Complications 0.546 0.296
## Preexisting.Diabetes 0.578 0.285 -0.255
## Gestational.Diabetes 0.285 0.558
## Mental.Health 0.560 0.289 0.161
## Heart.Rate 0.424 0.192
##
## PA1 PA2 PA3
## SS loadings 3.009 1.225 0.656
## Proportion Var 0.274 0.111 0.060
## Cumulative Var 0.274 0.385 0.445
cat("\n>> Jumlah faktor dengan eigenvalue > 1:", n_factors, "\n")
##
## >> Jumlah faktor dengan eigenvalue > 1: 3
4b. Communality
commun <- data.frame(Communality = round(fa_unrotated$communality, 3))
print(commun)
## Communality
## Age 0.203
## Systolic.BP 0.887
## Diastolic 0.692
## BS 0.713
## Body.Temp 0.126
## BMI 0.347
## Previous.Complications 0.395
## Preexisting.Diabetes 0.480
## Gestational.Diabetes 0.399
## Mental.Health 0.423
## Heart.Rate 0.225
4c. Factor Rotation
varimax <- fa(df2,
nfactors = n_factors,
rotate = "varimax",
fm = "pa",
use = "complete.obs")
4d. Interpretasi & Respecifikasi
# 1. Communality
print(varimax$loadings, cutoff = 0.4)
##
## Loadings:
## PA1 PA2 PA3
## Age 0.404
## Systolic.BP 0.923
## Diastolic 0.796
## BS 0.807
## Body.Temp
## BMI 0.434
## Previous.Complications 0.485
## Preexisting.Diabetes 0.684
## Gestational.Diabetes 0.615
## Mental.Health 0.459 0.457
## Heart.Rate
##
## PA1 PA2 PA3
## SS loadings 2.128 1.674 1.089
## Proportion Var 0.193 0.152 0.099
## Cumulative Var 0.193 0.346 0.445
commun_varimax <- data.frame(
Variabel = names(varimax$communality),
Communality = round(varimax$communality, 3)
)
print(commun_varimax)
## Variabel Communality
## Age Age 0.203
## Systolic.BP Systolic.BP 0.887
## Diastolic Diastolic 0.692
## BS BS 0.713
## Body.Temp Body.Temp 0.126
## BMI BMI 0.347
## Previous.Complications Previous.Complications 0.395
## Preexisting.Diabetes Preexisting.Diabetes 0.480
## Gestational.Diabetes Gestational.Diabetes 0.399
## Mental.Health Mental.Health 0.423
## Heart.Rate Heart.Rate 0.225
# 2. Variance
load_varimax <- as.matrix(varimax$loadings)
var_varimax <- data.frame(
Faktor = colnames(load_varimax),
SS_Loadings = round(colSums(load_varimax^2), 3),
Proporsi_Var = round(colSums(load_varimax^2) / ncol(df2) * 100, 2),
Kumulatif = round(cumsum(colSums(load_varimax^2) / ncol(df2)) * 100, 2)
)
print(var_varimax)
## Faktor SS_Loadings Proporsi_Var Kumulatif
## PA1 PA1 2.128 19.34 19.34
## PA2 PA2 1.674 15.22 34.56
## PA3 PA3 1.089 9.90 44.46
# 3. Cross loading
for (i in 1:nrow(load_varimax)) {
sig_idx <- which(abs(load_varimax[i, ]) >= 0.40)
if (length(sig_idx) > 1) {
vals <- sort(abs(load_varimax[i, sig_idx]), decreasing = TRUE)
ratio <- vals[1]^2 / vals[2]^2
if (ratio <= 1.5) {
status <- "kuat"
} else if (ratio <= 2.0) {
status <- "sedang"
} else {
status <- "lemah"
}
cat(sprintf("%-25s | %.3f vs %.3f | Ratio: %.2f | %s\n",
rownames(load_varimax)[i],
vals[1], vals[2], ratio, status))
}
}
## Mental.Health | 0.459 vs 0.457 | Ratio: 1.01 | kuat
# 4. Variabel per Faktor
for (j in 1:ncol(load_varimax)) {
vars_in_factor <- rownames(load_varimax)[abs(load_varimax[, j]) >= 0.40]
cat("Faktor", j, ":", paste(vars_in_factor, collapse = ", "), "\n")
}
## Faktor 1 : Age, BS, BMI, Previous.Complications, Preexisting.Diabetes, Mental.Health
## Faktor 2 : Systolic.BP, Diastolic
## Faktor 3 : Gestational.Diabetes, Mental.Health