#install.packages("readxl")
library(readxl) #Memasukkan Data ke R (Excel)
Data <- read_excel("D:/STATISTIKA 2021/SEMESTER 5/DATA MINING/Pertumbuhan Ekonomi SS - 2.xlsx")
View(Data)
str(Data)
## tibble [32 × 8] (S3: tbl_df/tbl/data.frame)
##  $ PertumbuhanEkonomi   : num [1:32] 24407 25836 26565 27807 26831 ...
##  $ Ekspor               : num [1:32] 15444 18961 19065 19400 20312 ...
##  $ Investasi            : num [1:32] 6070 5997 6695 7165 4577 ...
##  $ KonsumsiLSNirlaba    : num [1:32] 123 122 134 135 134 ...
##  $ KonsumsiRT           : num [1:32] 11920 12058 12361 12394 12415 ...
##  $ PengeluaranPemerintah: num [1:32] 1388 2083 2268 3244 1265 ...
##  $ PerubahanInventori   : num [1:32] 1617 -243 -342 418 755 ...
##  $ ImporAHK             : num [1:32] 12155 13142 13614 14948 12826 ...
dim(Data)
## [1] 32  8
# Korelasi Peubah Respons dengan Peubah Penjelas 
cor.test (Data$Ekspor, Data$PertumbuhanEkonomi)
## 
##  Pearson's product-moment correlation
## 
## data:  Data$Ekspor and Data$PertumbuhanEkonomi
## t = 16.13, df = 30, p-value = 2.504e-16
## alternative hypothesis: true correlation is not equal to 0
## 95 percent confidence interval:
##  0.8930807 0.9739998
## sample estimates:
##       cor 
## 0.9468991
cor.test (Data$Investasi, Data$PertumbuhanEkonomi)
## 
##  Pearson's product-moment correlation
## 
## data:  Data$Investasi and Data$PertumbuhanEkonomi
## t = 3.2815, df = 30, p-value = 0.002622
## alternative hypothesis: true correlation is not equal to 0
## 95 percent confidence interval:
##  0.2013304 0.7315395
## sample estimates:
##       cor 
## 0.5139441
cor.test (Data$KonsumsiRT, Data$PertumbuhanEkonomi)
## 
##  Pearson's product-moment correlation
## 
## data:  Data$KonsumsiRT and Data$PertumbuhanEkonomi
## t = 38.1, df = 30, p-value < 2.2e-16
## alternative hypothesis: true correlation is not equal to 0
## 95 percent confidence interval:
##  0.9790429 0.9950731
## sample estimates:
##       cor 
## 0.9898244
cor.test (Data$PengeluaranPemerintah, Data$PertumbuhanEkonomi)
## 
##  Pearson's product-moment correlation
## 
## data:  Data$PengeluaranPemerintah and Data$PertumbuhanEkonomi
## t = 2.2883, df = 30, p-value = 0.02934
## alternative hypothesis: true correlation is not equal to 0
## 95 percent confidence interval:
##  0.04251973 0.64719554
## sample estimates:
##       cor 
## 0.3854982
cor.test (Data$KonsumsiLSNirlaba, Data$PertumbuhanEkonomi)
## 
##  Pearson's product-moment correlation
## 
## data:  Data$KonsumsiLSNirlaba and Data$PertumbuhanEkonomi
## t = 18.759, df = 30, p-value < 2.2e-16
## alternative hypothesis: true correlation is not equal to 0
## 95 percent confidence interval:
##  0.9187501 0.9804427
## sample estimates:
##       cor 
## 0.9599212
cor.test (Data$PerubahanInventori, Data$PertumbuhanEkonomi)
## 
##  Pearson's product-moment correlation
## 
## data:  Data$PerubahanInventori and Data$PertumbuhanEkonomi
## t = -0.41622, df = 30, p-value = 0.6802
## alternative hypothesis: true correlation is not equal to 0
## 95 percent confidence interval:
##  -0.4135402  0.2803281
## sample estimates:
##        cor 
## -0.0757725
# Korelasi Antar Peubah Penjelas 
cor(as.matrix(Data[,c("Ekspor","Investasi", "KonsumsiRT","PengeluaranPemerintah",
                      "KonsumsiLSNirlaba","PerubahanInventori")]))
##                            Ekspor  Investasi  KonsumsiRT PengeluaranPemerintah
## Ekspor                 1.00000000  0.3243939  0.94503037             0.2415247
## Investasi              0.32439394  1.0000000  0.50452374             0.7759085
## KonsumsiRT             0.94503037  0.5045237  1.00000000             0.3446699
## PengeluaranPemerintah  0.24152468  0.7759085  0.34466994             1.0000000
## KonsumsiLSNirlaba      0.90275993  0.4975288  0.95734578             0.3573088
## PerubahanInventori    -0.05969282 -0.5590342 -0.05352549            -0.5065535
##                       KonsumsiLSNirlaba PerubahanInventori
## Ekspor                       0.90275993        -0.05969282
## Investasi                    0.49752881        -0.55903416
## KonsumsiRT                   0.95734578        -0.05352549
## PengeluaranPemerintah        0.35730882        -0.50655352
## KonsumsiLSNirlaba            1.00000000        -0.02929299
## PerubahanInventori          -0.02929299         1.00000000
# Analisis Regresi Berganda
Model_ARLB <- lm (PertumbuhanEkonomi ~ Ekspor + Investasi + KonsumsiRT + PengeluaranPemerintah 
                  + KonsumsiLSNirlaba + PerubahanInventori, data=Data)
summary (Model_ARLB)
## 
## Call:
## lm(formula = PertumbuhanEkonomi ~ Ekspor + Investasi + KonsumsiRT + 
##     PengeluaranPemerintah + KonsumsiLSNirlaba + PerubahanInventori, 
##     data = Data)
## 
## Residuals:
##      Min       1Q   Median       3Q      Max 
## -1157.81  -271.66    44.58   357.95   581.70 
## 
## Coefficients:
##                         Estimate Std. Error t value Pr(>|t|)    
## (Intercept)           -1.255e+03  1.679e+03  -0.747    0.462    
## Ekspor                 1.812e-01  1.070e-01   1.694    0.103    
## Investasi              4.387e-02  2.095e-01   0.209    0.836    
## KonsumsiRT             1.777e+00  3.618e-01   4.910  4.7e-05 ***
## PengeluaranPemerintah  2.551e-01  1.598e-01   1.596    0.123    
## KonsumsiLSNirlaba      1.724e+01  1.149e+01   1.501    0.146    
## PerubahanInventori     6.201e-02  1.723e-01   0.360    0.722    
## ---
## Signif. codes:  0 '***' 0.001 '**' 0.01 '*' 0.05 '.' 0.1 ' ' 1
## 
## Residual standard error: 490.4 on 25 degrees of freedom
## Multiple R-squared:  0.986,  Adjusted R-squared:  0.9826 
## F-statistic:   293 on 6 and 25 DF,  p-value: < 2.2e-16
# Uji Asumsi Klasik
library(performance)

# Uji Normalitas 
check_normality(Model_ARLB)
## OK: residuals appear as normally distributed (p = 0.074).
# Uji Heteroskedastisitas
check_heteroscedasticity(Model_ARLB)
## Warning: Heteroscedasticity (non-constant error variance) detected (p = 0.021).
# Uji Multikolinieritas
multicollinearity(Model_ARLB)
## # Check for Multicollinearity
## 
## Low Correlation
## 
##                   Term  VIF     VIF 95% CI Increased SE Tolerance
##  PengeluaranPemerintah 2.69 [ 1.88,  4.21]         1.64      0.37
##     PerubahanInventori 2.38 [ 1.70,  3.72]         1.54      0.42
##  Tolerance 95% CI
##      [0.24, 0.53]
##      [0.27, 0.59]
## 
## Moderate Correlation
## 
##       Term  VIF     VIF 95% CI Increased SE Tolerance Tolerance 95% CI
##  Investasi 6.64 [ 4.28, 10.70]         2.58      0.15     [0.09, 0.23]
## 
## High Correlation
## 
##               Term   VIF     VIF 95% CI Increased SE Tolerance Tolerance 95% CI
##             Ekspor 19.66 [12.20, 32.09]         4.43      0.05     [0.03, 0.08]
##         KonsumsiRT 33.62 [20.69, 55.04]         5.80      0.03     [0.02, 0.05]
##  KonsumsiLSNirlaba 12.51 [ 7.85, 20.33]         3.54      0.08     [0.05, 0.13]
# Uji Autokorelasi
check_autocorrelation(Model_ARLB)
## Warning: Autocorrelated residuals detected (p < .001).
# Cek Performa/Kinerja Model
model_performance(Model_ARLB,metrics = "all")
## # Indices of model performance
## 
## AIC     |    AICc |     BIC |    R2 | R2 (adj.) |    RMSE |   Sigma
## -------------------------------------------------------------------
## 495.407 | 501.668 | 507.133 | 0.986 |     0.983 | 433.456 | 490.400
# Hasil Prediksi Model (y_dugaARLB)
y_dugaARLB <- predict(Model_ARLB)
y_dugaARLB
##        1        2        3        4        5        6        7        8 
## 25564.91 26482.29 27313.54 27779.46 27356.65 27708.64 28199.67 28615.90 
##        9       10       11       12       13       14       15       16 
## 28806.70 29350.76 29867.20 30269.61 30248.57 30650.83 31395.33 31758.38 
##       17       18       19       20       21       22       23       24 
## 31324.79 31832.85 32746.12 33323.52 32577.95 33591.71 34729.15 35011.14 
##       25       26       27       28       29       30       31       32 
## 34497.53 35587.89 36513.37 37261.05 36490.88 37456.81 37865.22 38467.39
# Korelasi Antara Pertumbuhan Ekonomi dan Y Duga
cor.test (Data$PertumbuhanEkonomi, y_dugaARLB)
## 
##  Pearson's product-moment correlation
## 
## data:  Data$PertumbuhanEkonomi and y_dugaARLB
## t = 45.927, df = 30, p-value < 2.2e-16
## alternative hypothesis: true correlation is not equal to 0
## 95 percent confidence interval:
##  0.9854842 0.9965959
## sample estimates:
##       cor 
## 0.9929637

ANALISIS REGRESI TERPENALTI

# Analisis Regresi Ridge (Gulud)
x <- data.matrix(Data[, c('Ekspor', 'Investasi', 'KonsumsiRT','PengeluaranPemerintah'
                          , 'KonsumsiLSNirlaba', 'PerubahanInventori')])
head(x)
##        Ekspor Investasi KonsumsiRT PengeluaranPemerintah KonsumsiLSNirlaba
## [1,] 15443.83   6070.14   11919.53               1388.04            123.15
## [2,] 18961.48   5996.57   12057.78               2083.34            121.72
## [3,] 19064.53   6694.59   12360.51               2267.53            133.51
## [4,] 19400.01   7164.88   12394.40               3243.64            135.14
## [5,] 20312.28   4576.75   12414.77               1265.14            133.58
## [6,] 20089.67   5706.60   12528.48               2137.20            132.44
##      PerubahanInventori
## [1,]            1617.14
## [2,]            -242.78
## [3,]            -342.07
## [4,]             417.87
## [5,]             754.61
## [6,]            -246.67
dim(x)
## [1] 32  6
y <- Data$PertumbuhanEkonomi
head(y)
## [1] 24407.10 25835.93 26564.60 27807.45 26831.47 28066.35
model_coba1 <- lm (y~x)
summary (model_coba1)
## 
## Call:
## lm(formula = y ~ x)
## 
## Residuals:
##      Min       1Q   Median       3Q      Max 
## -1157.81  -271.66    44.58   357.95   581.70 
## 
## Coefficients:
##                          Estimate Std. Error t value Pr(>|t|)    
## (Intercept)            -1.255e+03  1.679e+03  -0.747    0.462    
## xEkspor                 1.812e-01  1.070e-01   1.694    0.103    
## xInvestasi              4.387e-02  2.095e-01   0.209    0.836    
## xKonsumsiRT             1.777e+00  3.618e-01   4.910  4.7e-05 ***
## xPengeluaranPemerintah  2.551e-01  1.598e-01   1.596    0.123    
## xKonsumsiLSNirlaba      1.724e+01  1.149e+01   1.501    0.146    
## xPerubahanInventori     6.201e-02  1.723e-01   0.360    0.722    
## ---
## Signif. codes:  0 '***' 0.001 '**' 0.01 '*' 0.05 '.' 0.1 ' ' 1
## 
## Residual standard error: 490.4 on 25 degrees of freedom
## Multiple R-squared:  0.986,  Adjusted R-squared:  0.9826 
## F-statistic:   293 on 6 and 25 DF,  p-value: < 2.2e-16
#install.packages("glmnet")
library(glmnet)
## Loading required package: Matrix
## Loaded glmnet 4.1-8
#Melakukan k-fold cross-validation untuk menemukan nilai lambda yang optimal
cv_model <- cv.glmnet(x, y, alpha = 0)
#temukan nilai lambda optimal yang meminimalkan tes MSE
best_lambda <- cv_model$lambda.min
best_lambda
## [1] 362.3103
log (best_lambda)
## [1] 5.892501
log(cv_model$lambda.1se)
## [1] 6.729805
#menghasilkan plot uji MSE dengan nilai lambda
plot(cv_model) 

#menemukan koefisien model terbaik
Model_Ridge <- glmnet(x, y, alpha = 0, lambda = best_lambda)
coef(Model_Ridge)
## 7 x 1 sparse Matrix of class "dgCMatrix"
##                                 s0
## (Intercept)           2743.1419682
## Ekspor                   0.3110970
## Investasi                0.2678929
## KonsumsiRT               0.9834074
## PengeluaranPemerintah    0.1902167
## KonsumsiLSNirlaba       34.0211991
## PerubahanInventori       0.1576684
summary (Model_Ridge)
##           Length Class     Mode   
## a0        1      -none-    numeric
## beta      6      dgCMatrix S4     
## df        1      -none-    numeric
## dim       2      -none-    numeric
## lambda    1      -none-    numeric
## dev.ratio 1      -none-    numeric
## nulldev   1      -none-    numeric
## npasses   1      -none-    numeric
## jerr      1      -none-    numeric
## offset    1      -none-    logical
## call      5      -none-    call   
## nobs      1      -none-    numeric
# Hasil Prediksi Model (y_dugaARidge)
y_dugaRidge <- predict(Model_Ridge,newx=x[1:32,])
y_dugaRidge
##             s0
##  [1,] 25604.28
##  [2,] 26605.22
##  [3,] 27542.47
##  [4,] 28167.10
##  [5,] 27401.27
##  [6,] 27715.74
##  [7,] 28303.04
##  [8,] 28966.02
##  [9,] 29142.33
## [10,] 29744.82
## [11,] 29897.70
## [12,] 30337.26
## [13,] 30407.97
## [14,] 30861.43
## [15,] 31414.93
## [16,] 31802.25
## [17,] 31171.15
## [18,] 31622.48
## [19,] 32554.52
## [20,] 33227.16
## [21,] 32144.19
## [22,] 33280.30
## [23,] 34602.48
## [24,] 34876.59
## [25,] 34404.14
## [26,] 35214.04
## [27,] 36503.79
## [28,] 37415.38
## [29,] 36687.59
## [30,] 37424.67
## [31,] 37477.29
## [32,] 38126.23
# Menghitung R^2 adjusted dari nilai sebenarnya dan prediksi
SSE <- sum((y_dugaRidge - y)^2)
SST <- sum((y - mean(y))^2)
RSquared_Ridge <- 1 - (SSE / SST)*(31/26) #((n-1)/(n-p-1)
RSquared_Ridge
## [1] 0.9787964
# Root Mean Square Error (RMSE) 
RMSE_Ridge <- sqrt(mean((y - y_dugaRidge)^2))
RMSE_Ridge
## [1] 488.1274
#Ukuran Kinerja/Performa untuk Model glmnet
Performance_Ridge <- assess.glmnet(Model_Ridge,newx=x[1:32,], newy=y)
RMSE_Ridge1 <- sqrt(Performance_Ridge$mse)
RMSE_Ridge1
##       s0 
## 488.1274 
## attr(,"measure")
## [1] "Mean-Squared Error"
# Korelasi Antara Pertumbuhan Ekonomi dan Y Duga
cor.test (y, y_dugaRidge)
## 
##  Pearson's product-moment correlation
## 
## data:  y and y_dugaRidge
## t = 41.906, df = 30, p-value < 2.2e-16
## alternative hypothesis: true correlation is not equal to 0
## 95 percent confidence interval:
##  0.9826144 0.9959183
## sample estimates:
##       cor 
## 0.9915663

Analisis Regresi LASSO

model_coba1 <- lm (y~x)
summary (model_coba1)
## 
## Call:
## lm(formula = y ~ x)
## 
## Residuals:
##      Min       1Q   Median       3Q      Max 
## -1157.81  -271.66    44.58   357.95   581.70 
## 
## Coefficients:
##                          Estimate Std. Error t value Pr(>|t|)    
## (Intercept)            -1.255e+03  1.679e+03  -0.747    0.462    
## xEkspor                 1.812e-01  1.070e-01   1.694    0.103    
## xInvestasi              4.387e-02  2.095e-01   0.209    0.836    
## xKonsumsiRT             1.777e+00  3.618e-01   4.910  4.7e-05 ***
## xPengeluaranPemerintah  2.551e-01  1.598e-01   1.596    0.123    
## xKonsumsiLSNirlaba      1.724e+01  1.149e+01   1.501    0.146    
## xPerubahanInventori     6.201e-02  1.723e-01   0.360    0.722    
## ---
## Signif. codes:  0 '***' 0.001 '**' 0.01 '*' 0.05 '.' 0.1 ' ' 1
## 
## Residual standard error: 490.4 on 25 degrees of freedom
## Multiple R-squared:  0.986,  Adjusted R-squared:  0.9826 
## F-statistic:   293 on 6 and 25 DF,  p-value: < 2.2e-16
library(glmnet)

#Melakukan k-fold cross-validation untuk menemukan nilai lambda yang optimal
cv_model <- cv.glmnet(x, y, alpha = 1)
#temukan nilai lambda optimal yang meminimalkan tes MSE
best_lambda <- cv_model$lambda.min
best_lambda
## [1] 55.06795
log (best_lambda)
## [1] 4.008568
log(cv_model$lambda.1se)
## [1] 5.497108
#menghasilkan plot uji MSE dengan nilai lambda
plot(cv_model) 

#menemukan koefisien model terbaik
Model_Lasso <- glmnet(x, y, alpha = 1, lambda = best_lambda)
coef(Model_Lasso)
## 7 x 1 sparse Matrix of class "dgCMatrix"
##                                 s0
## (Intercept)           -988.0902760
## Ekspor                   0.1433721
## Investasi                .        
## KonsumsiRT               1.8444796
## PengeluaranPemerintah    0.1997886
## KonsumsiLSNirlaba       17.8770354
## PerubahanInventori       .
summary (Model_Lasso)
##           Length Class     Mode   
## a0        1      -none-    numeric
## beta      6      dgCMatrix S4     
## df        1      -none-    numeric
## dim       2      -none-    numeric
## lambda    1      -none-    numeric
## dev.ratio 1      -none-    numeric
## nulldev   1      -none-    numeric
## npasses   1      -none-    numeric
## jerr      1      -none-    numeric
## offset    1      -none-    logical
## call      5      -none-    call   
## nobs      1      -none-    numeric
# Hasil Prediksi Model (y_dugaARLasso)
y_dugaLasso <- predict(Model_Lasso,newx=x[1:32,])
y_dugaLasso
##             s0
##  [1,] 25690.33
##  [2,] 26563.01
##  [3,] 27383.73
##  [4,] 27718.49
##  [5,] 27463.69
##  [6,] 27795.36
##  [7,] 28227.59
##  [8,] 28681.61
##  [9,] 28857.97
## [10,] 29374.87
## [11,] 29893.72
## [12,] 30291.08
## [13,] 30288.95
## [14,] 30655.27
## [15,] 31397.27
## [16,] 31737.51
## [17,] 31390.58
## [18,] 31869.39
## [19,] 32752.89
## [20,] 33270.97
## [21,] 32668.18
## [22,] 33575.09
## [23,] 34666.16
## [24,] 34847.41
## [25,] 34520.59
## [26,] 35598.22
## [27,] 36398.45
## [28,] 37107.64
## [29,] 36485.24
## [30,] 37391.84
## [31,] 37811.44
## [32,] 38271.27
# Menghitung R^2 adjusted dari nilai sebenarnya dan prediksi
SSE <- sum((y_dugaLasso - y)^2)
SST <- sum((y - mean(y))^2)
RSquared_Lasso <- 1 - (SSE / SST)*(31/27) #((n-1)/(n-p-1)
RSquared_Lasso
## [1] 0.983385
# Root Mean Square Error (RMSE) 
RMSE_Lasso <- sqrt(mean((y - y_dugaLasso)^2))
RMSE_Lasso
## [1] 440.3258
#Ukuran Kinerja/Performa untuk Model glmnet
Performance_Lasso <- assess.glmnet(Model_Lasso,newx=x[1:32,], newy=y)
RMSE_Lasso1 <- sqrt(Performance_Lasso$mse)
RMSE_Lasso1
##       s0 
## 440.3258 
## attr(,"measure")
## [1] "Mean-Squared Error"
# Korelasi Antara Pertumbuhan Ekonomi dan Y Duga
cor.test (y, y_dugaLasso)
## 
##  Pearson's product-moment correlation
## 
## data:  y and y_dugaLasso
## t = 45.608, df = 30, p-value < 2.2e-16
## alternative hypothesis: true correlation is not equal to 0
## 95 percent confidence interval:
##  0.9852832 0.9965484
## sample estimates:
##       cor 
## 0.9928659

Analisis Regresi Elastic Net

model_coba1 <- lm (y~x)
summary (model_coba1)
## 
## Call:
## lm(formula = y ~ x)
## 
## Residuals:
##      Min       1Q   Median       3Q      Max 
## -1157.81  -271.66    44.58   357.95   581.70 
## 
## Coefficients:
##                          Estimate Std. Error t value Pr(>|t|)    
## (Intercept)            -1.255e+03  1.679e+03  -0.747    0.462    
## xEkspor                 1.812e-01  1.070e-01   1.694    0.103    
## xInvestasi              4.387e-02  2.095e-01   0.209    0.836    
## xKonsumsiRT             1.777e+00  3.618e-01   4.910  4.7e-05 ***
## xPengeluaranPemerintah  2.551e-01  1.598e-01   1.596    0.123    
## xKonsumsiLSNirlaba      1.724e+01  1.149e+01   1.501    0.146    
## xPerubahanInventori     6.201e-02  1.723e-01   0.360    0.722    
## ---
## Signif. codes:  0 '***' 0.001 '**' 0.01 '*' 0.05 '.' 0.1 ' ' 1
## 
## Residual standard error: 490.4 on 25 degrees of freedom
## Multiple R-squared:  0.986,  Adjusted R-squared:  0.9826 
## F-statistic:   293 on 6 and 25 DF,  p-value: < 2.2e-16
#install.packages("glmnet")
library(glmnet)

#Melakukan k-fold cross-validation untuk menemukan nilai lambda yang optimal
cv_model <- cv.glmnet(x, y, alpha = 0.75)
#temukan nilai lambda optimal yang meminimalkan tes MSE
best_lambda <- cv_model$lambda.min
best_lambda
## [1] 55.54251
log (best_lambda)
## [1] 4.017149
log(cv_model$lambda.1se)
## [1] 5.505689
#menghasilkan plot uji MSE dengan nilai lambda
plot(cv_model) 

#menemukan koefisien model terbaik
Model_ENet <- glmnet(x, y, alpha = 0.75, lambda = best_lambda)
coef(Model_ENet)
## 7 x 1 sparse Matrix of class "dgCMatrix"
##                                  s0
## (Intercept)           -4.496944e+02
## Ekspor                 1.690125e-01
## Investasi              9.676272e-03
## KonsumsiRT             1.721687e+00
## PengeluaranPemerintah  2.131709e-01
## KonsumsiLSNirlaba      2.095169e+01
## PerubahanInventori     .
summary (Model_ENet)
##           Length Class     Mode   
## a0        1      -none-    numeric
## beta      6      dgCMatrix S4     
## df        1      -none-    numeric
## dim       2      -none-    numeric
## lambda    1      -none-    numeric
## dev.ratio 1      -none-    numeric
## nulldev   1      -none-    numeric
## npasses   1      -none-    numeric
## jerr      1      -none-    numeric
## offset    1      -none-    logical
## call      5      -none-    call   
## nobs      1      -none-    numeric
# Hasil Prediksi Model (y_dugaENet)
y_dugaENet <- predict(Model_ENet,newx=x[1:32,])
y_dugaENet
##             s0
##  [1,] 25617.03
##  [2,] 26567.13
##  [3,] 27398.79
##  [4,] 27760.62
##  [5,] 27470.39
##  [6,] 27801.48
##  [7,] 28174.22
##  [8,] 28688.94
##  [9,] 28880.76
## [10,] 29420.98
## [11,] 29869.18
## [12,] 30304.77
## [13,] 30321.96
## [14,] 30682.90
## [15,] 31384.36
## [16,] 31752.26
## [17,] 31358.54
## [18,] 31830.51
## [19,] 32704.99
## [20,] 33274.87
## [21,] 32595.09
## [22,] 33526.57
## [23,] 34668.21
## [24,] 34850.15
## [25,] 34504.73
## [26,] 35566.67
## [27,] 36424.42
## [28,] 37216.43
## [29,] 36529.94
## [30,] 37421.36
## [31,] 37807.78
## [32,] 38269.77
# Menghitung R^2 adjusted dari nilai sebenarnya dan prediksi
SSE <- sum((y_dugaENet - y)^2)
SST <- sum((y - mean(y))^2)
RSquared_ENet <- 1 - (SSE / SST)*(31/27) #((n-1)/(n-p-1)
RSquared_ENet
## [1] 0.9834757
# Root Mean Square Error (RMSE) 
RMSE_ENet <- sqrt(mean((y - y_dugaENet)^2))
RMSE_ENet
## [1] 439.1226
#Ukuran Kinerja/Performa untuk Model glmnet
Performance_ENet <- assess.glmnet(Model_ENet,newx=x[1:32,], newy=y)
RMSE_ENet1 <- sqrt(Performance_ENet$mse)
RMSE_ENet1
##       s0 
## 439.1226 
## attr(,"measure")
## [1] "Mean-Squared Error"
# Korelasi Antara Pertumbuhan Ekonomi dan Y Duga
cor.test (y, y_dugaENet)
## 
##  Pearson's product-moment correlation
## 
## data:  y and y_dugaENet
## t = 45.643, df = 30, p-value < 2.2e-16
## alternative hypothesis: true correlation is not equal to 0
## 95 percent confidence interval:
##  0.9853057 0.9965537
## sample estimates:
##       cor 
## 0.9928768