BAB V KESIMPULAN DAN SARAN
5.2. Saran
1. Bagi peneliti selanjutnya agar dapat meneliti lebih lanjut tentang faktor-faktor yang mempengaruhi impor gula Indonesia selain variabel yang ada dalam penelitian ini agar diperoleh pengaruh yang lebih signifik
2. Bagi pemerintah agar dapat menekan mengurangi laju volume impor gula di Indonesia. Adapun dalam mengurangi laju volume impor gula antara lain: (1) strategi, program dan dukungan yang nyata untuk meningkatkan produksi dan produktivitas gula, (2) pemerintah harus memiliki mekanisme yang tepat untuk memelihara kestabilan kurs Rupiah, (3) mencari barang substitusi sebagai bahan pemanis yang lain untuk mengurangi konsumsi gula pasir yang
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tinggi, dan (4) penguatan lembaga dan dukungan permodalan untuk para usaha gula di Indonesia.
DAFTAR PUSTAKA
Ajija, Shochrul R.,dkk. 2011. Cara Cerdas Menguasai Eviews. Jakarta: Salemba Empat.
Badan Perencanaan Pembanguna Nasional. 2014. Studi Pendahuluan Rencana Pembangunan Jangka Menengah Nasional (RPJMN) Bidang Pangan dan Pertanian 2015-2019. Jakarta
Badan Pusat Statistik. 2000-2018. Statistik Indonesia. Jakarta.
Calton, W. D., K. T. Harman, and H. Williamson. 2016. Species 2000 and ITIS Catalogue of Life. Royal Botanic Gardens Kew. Surrey.
Chen, C. 2002. Regression and Outlier Detection with the Robustreg Procedure.
Statstcs and Data Analysis. SAS Institute: Cary, NC.
Christianto, Edward. 2013. Faktor Yang Mempengaruhi Volume Impor Beras di Indonesia. Jurnal JIBENKA Volume 7 No.2
Dahlan, D. 2011. Buku Ajar Mata Kuliah Budidaya Tanaman Industri. Fakultas Pertanian, Universitas Hasanuddin.
Draper, N.R. and Smith, H. 1992. Analisis Regresi Terapan. Ed. Ke-2.
Diterjemahkkan olehnBambang Sumantri. Gramedia Pustaka Utama, Jakarta.
Fox, J. 2002. Robust Regression. Tersedia di: http://cran.r-project.org/doc/contrib/Fox-Companion/appendix-robust-regression.pdf (15 Desember 2010
Gujarati, Damodar. 1988. Basic Econometric, International Edition. McGraw-Hill Book Company. Boston.
_______________. 1991. Basic Econometric, International Edition. McGraw-Hill Book Company. Boston.
_______________. 1995. Basic Econometrics, 3th Ed. McGraw-Hill.
Harsoyo, Y. 2004. βMembangkitkan Kembali Agroindustri Gula Nasionalβ.
Antisipasi Vol.8 No.1
Krugman, Paul, R, dan Obstfeld, Maurice, 2005. Ekonomi Internasional Teori dan Kebijaksanaan, Rajawali Pers, Jakarta.
Mubyanto. 1984. Pengantar Ekonomi Pertanian. LP3ES. Yogyakarta.
Myers, R.H. 1990. Clasical and Modern Regression With Application.
PWSKENT publihing Company, Boston.
Olive, D.J, 2005. Applied Robust Statistic. Carbondale: Southern Illinois University.
P3GI, 1992. Statistik Tanaman Tebu, Pasuruan : P3GI.
Salvatore. 2014. Ekonomi Internasional. BPFE. Yogyakarta.
Sapuan, 1998. Kebijaksanaan Pergulaan dan Perkembangan Tata Niaga Gula di Indonesia, Available online at www.bulog.go.id\papers\k_001gula.html Steenis, C.G.C.J.V., G.D> Hoed, dan P.J. Emya. 2005. Flora. PT. Pradnya
Paramita. Jakarta.
Sudiatso, S. 1982. Bertanam Tebu. Fakultas Pertanian, Institut Pertanian Bogor.
Sumodiningrat, Gunawan, 1994. Ekonometrika, Yogyakarta : BPFE - UGM.
Sumodiningrat, Gunawan. 2010. Ekonometrika Pengantar. Yogyakarta:
BPFEYogyakarta.
Susila dan Bonar M. Sinaga, 2005. Analisis Kebijakan Industri Gula Indonesia, Jurnal Agro Ekonomi, Vol. 23 No.1.
Wijayanti, W.A. 2008. Pengelolaan Tanaman Tebu (Saccharum Officinarum L.) di Pabrik Gula Tjoekir PTPN X. Jombang, Jawa Timur; Studi Kasus Pengaruh Bongkar Ratoon terhadap Peningkatan Produktivitas Tebu.
Skripsi Institut Pertanian Bogor.
Wilcox, R.R. 2005. Introduction to Robust Estimation and Hypothesis. San Diego: Academic Press.
LAMPIRAN
Lampiran 1. Data Analisis Volume Impor Gula Indonesia
Lampiran 2. Hasil Uji Stasioner dengan E-Views 10 Y (Volume Impor Gula) : Level
Null Hypothesis: Y has a unit root Exogenous: Constant
Lag Length: 1 (Automatic - based on SIC, maxlag=9)
t-Statistic Prob.*
Augmented Dickey-Fuller test statistic 1.378641 0.9986
Test critical values: 1% level -3.615588
5% level -2.941145
10% level -2.609066
*MacKinnon (1996) one-sided p-values.
Y (Volume Impor Gula) : πππ difference
Null Hypothesis: D(Y) has a unit root Exogenous: Constant
Lag Length: 0 (Automatic - based on SIC, maxlag=9)
t-Statistic Prob.*
Augmented Dickey-Fuller test statistic -8.922985 0.0000
Test critical values: 1% level -3.615588
5% level -2.941145
10% level -2.609066
*MacKinnon (1996) one-sided p-values.
X1 (Nilai tukar Rupiah terhadap Dollar/Kurs) : Level
Null Hypothesis: X1 has a unit root Exogenous: Constant
Lag Length: 0 (Automatic - based on SIC, maxlag=9)
t-Statistic Prob.*
Augmented Dickey-Fuller test statistic -0.403436 0.8987
Test critical values: 1% level -3.610453
5% level -2.938987
10% level -2.607932
*MacKinnon (1996) one-sided p-values.
X1 (Nilai tukar Rupiah terhadap Dollar/Kurs) : πππ difference
Null Hypothesis: D(X1) has a unit root Exogenous: Constant
Lag Length: 0 (Automatic - based on SIC, maxlag=9)
t-Statistic Prob.*
Augmented Dickey-Fuller test statistic -7.393045 0.0000
Test critical values: 1% level -3.615588
5% level -2.941145
10% level -2.609066
*MacKinnon (1996) one-sided p-values.
X2 (Sugar Domestic Demand) : Level
Null Hypothesis: X2 has a unit root Exogenous: Constant
Lag Length: 0 (Automatic - based on SIC, maxlag=9)
t-Statistic Prob.*
Augmented Dickey-Fuller test statistic 1.065699 0.9965
Test critical values: 1% level -3.610453
5% level -2.938987
10% level -2.607932
*MacKinnon (1996) one-sided p-values.
X2 (Sugar Domestic Demand) : πππ difference
Null Hypothesis: D(X2) has a unit root Exogenous: Constant
Lag Length: 0 (Automatic - based on SIC, maxlag=9)
t-Statistic Prob.*
Augmented Dickey-Fuller test statistic -7.230627 0.0000
Test critical values: 1% level -3.615588
5% level -2.941145
10% level -2.609066
*MacKinnon (1996) one-sided p-values.
X3 (Produksi Gula Indonesiaa) : Level
Null Hypothesis: X3 has a unit root Exogenous: Constant
Lag Length: 0 (Automatic - based on SIC, maxlag=9)
t-Statistic Prob.*
Augmented Dickey-Fuller test statistic -2.144275 0.2293
Test critical values: 1% level -3.610453
5% level -2.938987
10% level -2.607932
*MacKinnon (1996) one-sided p-values.
X3 (Produksi Gula Indonesiaa) : πππ difference
Null Hypothesis: D(X3) has a unit root Exogenous: Constant
Lag Length: 0 (Automatic - based on SIC, maxlag=9)
t-Statistic Prob.*
Augmented Dickey-Fuller test statistic -6.133025 0.0000
Test critical values: 1% level -3.615588
5% level -2.941145
10% level -2.609066
*MacKinnon (1996) one-sided p-values.
X4 (Sugar Lagged Import) : Level
Null Hypothesis: X4 has a unit root Exogenous: Constant
Lag Length: 1 (Automatic - based on SIC, maxlag=9)
t-Statistic Prob.*
Augmented Dickey-Fuller test statistic 0.801421 0.9928
Test critical values: 1% level -3.615588
5% level -2.941145
10% level -2.609066
*MacKinnon (1996) one-sided p-values.
X4 (Sugar Lagged Import) : πππ difference
Null Hypothesis: D(X4) has a unit root Exogenous: Constant
Lag Length: 0 (Automatic - based on SIC, maxlag=9)
t-Statistic Prob.*
Augmented Dickey-Fuller test statistic -9.251523 0.0000
Test critical values: 1% level -3.615588
5% level -2.941145
10% level -2.609066
*MacKinnon (1996) one-sided p-values.
Grafik Sebelum dan Sesudah Uji Stasioneritas 1. Volume Impor Gula di Indonesia (Y)
0
1980 1985 1990 1995 2000 2005 2010 2015
Y
1980 1985 1990 1995 2000 2005 2010 2015
Differenced Y
2. Nilai Tukar Rupiah terhadap Dollar/Kurs (X1)
0
1980 1985 1990 1995 2000 2005 2010 2015
X1
1980 1985 1990 1995 2000 2005 2010 2015
Differenced X1
1980 1985 1990 1995 2000 2005 2010 2015
X2
1980 1985 1990 1995 2000 2005 2010 2015
Differenced X2
4. Produksi Gula Indonesia (X3)
1980 1985 1990 1995 2000 2005 2010 2015
X3
1980 1985 1990 1995 2000 2005 2010 2015
Differenced X3
1980 1985 1990 1995 2000 2005 2010 2015
X4
1980 1985 1990 1995 2000 2005 2010 2015
Differenced X4
Lampiran 3. Hasil Uji Kointegrasi dengan E-Views-10 Date: 09/15/20 Time: 00:56
Sample (adjusted): 1981 2018
Included observations: 38 after adjustments Trend assumption: Linear deterministic trend Series: X1 X2 X3 X4 Y
Lags interval (in first differences): 1 to 1
Unrestricted Cointegration Rank Test (Trace)
Hypothesized Trace 0.05
No. of CE(s) Eigenvalue Statistic Critical Value Prob.**
None * 0.769390 93.50328 69.81889 0.0002 At most 1 0.427143 37.75632 47.85613 0.3127 At most 2 0.291037 16.58577 29.79707 0.6704 At most 3 0.088134 3.515612 15.49471 0.9387 At most 4 0.000254 0.009647 3.841466 0.9215 Trace test indicates 1 cointegrating eqn(s) at the 0.05 level
* denotes rejection of the hypothesis at the 0.05 level **MacKinnon-Haug-Michelis (1999) p-values
Unrestricted Cointegration Rank Test (Maximum Eigenvalue)
Hypothesized Max-Eigen 0.05
No. of CE(s) Eigenvalue Statistic Critical Value Prob.**
None * 0.769390 55.74696 33.87687 0.0000 At most 1 0.427143 21.17054 27.58434 0.2660 At most 2 0.291037 13.07016 21.13162 0.4458 At most 3 0.088134 3.505965 14.26460 0.9075 At most 4 0.000254 0.009647 3.841466 0.9215 Max-eigenvalue test indicates 1 cointegrating eqn(s) at the 0.05 level * denotes rejection of the hypothesis at the 0.05 level
**MacKinnon-Haug-Michelis (1999) p-values
Unrestricted Cointegrating Coefficients (normalized by b'*S11*b=I):
X1 X2 X3 X4 Y
Unrestricted Adjustment Coefficients (alpha):
Normalized cointegrating coefficients (standard error in parentheses)
X1 X2 X3 X4 Y
1.000000 0.002416 -0.005076 -0.048544 0.044483 (0.00057) (0.00078) (0.00386) (0.00384) Adjustment coefficients (standard error in parentheses)
D(X1) -0.365184
Normalized cointegrating coefficients (standard error in parentheses)
X1 X2 X3 X4 Y
1.000000 0.000000 -0.002647 -0.042365 0.039848 (0.00055) (0.00367) (0.00380) 0.000000 1.000000 -1.005635 -2.557043 1.918187 (0.16792) (1.12151) (1.16307) Adjustment coefficients (standard error in parentheses)
D(X1) -0.533462 0.000311
D(Y) 144.5452 1.111371
Normalized cointegrating coefficients (standard error in parentheses)
X1 X2 X3 X4 Y Adjustment coefficients (standard error in parentheses)
D(X1) -0.550768 0.000435 0.000636
Normalized cointegrating coefficients (standard error in parentheses)
X1 X2 X3 X4 Y Adjustment coefficients (standard error in parentheses)
D(X1) -0.554710 0.000447 0.000653 0.022270 (0.10443) (0.00048) (0.00058) (0.00421) D(X2) 66.39138 0.046095 0.001301 -3.035448 (27.8010) (0.12676) (0.15559) (1.12009)
(27.2899) (0.12443) (0.15273) (1.09949) D(X4) 7.851859 -0.006838 0.001649 -0.456837 (4.82798) (0.02201) (0.02702) (0.19452) D(Y) 149.6689 1.098387 -1.540710 -8.802106 (43.0416) (0.19625) (0.24089) (1.73412)
Lampiran 4. Hasil Uji Asumsi Klasik dengan E-Views 10
-999998 -499998 3 500003 1000003 1500003
Series: Residuals
Coefficient Uncentered Centered
Variable Variance VIF VIF
3. Uji Heterokedastisita
Heteroskedasticity Test: Breusch-Pagan-Godfrey
F-statistic 0.611868 Prob. F(4,35) 0.6569
Obs*R-squared 2.614297 Prob. Chi-Square(4) 0.6243 Scaled explained SS 3.936427 Prob. Chi-Square(4) 0.4147
Test Equation:
Dependent Variable: RESID^2 Method: Least Squares
Date: 09/15/20 Time: 00:50 Sample: 1979 2018
Included observations: 40
Variable Coefficient Std. Error t-Statistic Prob.
C 8.71E+10 3.33E+11 0.261035 0.7956
X1 17362573 29477522 0.589011 0.5596
X2 -132682.0 126593.6 -1.048094 0.3018
X3 153731.1 203899.5 0.753955 0.4559
X4 104816.1 124495.4 0.841927 0.4055
R-squared 0.065357 Mean dependent var 1.90E+11
Adjusted R-squared -0.041459 S.D. dependent var 3.81E+11 S.E. of regression 3.89E+11 Akaike info criterion 56.32763 Sum squared resid 5.29E+24 Schwarz criterion 56.53874 Log likelihood -1121.553 Hannan-Quinn criter. 56.40396 F-statistic 0.611868 Durbin-Watson stat 1.891871 Prob(F-statistic) 0.656859
4. Uji Autokorrelasi
Breusch-Godfrey Serial Correlation LM Test:
F-statistic 2.492147 Prob. F(2,33) 0.0982
Obs*R-squared 5.248795 Prob. Chi-Square(2) 0.0725
Test Equation:
Dependent Variable: RESID Method: Least Squares Date: 09/15/20 Time: 00:49 Sample: 1979 2018
Included observations: 40
Presample missing value lagged residuals set to zero.
Variable Coefficient Std. Error t-Statistic Prob.
C 191145.0 394139.2 0.484968 0.6309
X1 -87.00228 54.38001 -1.599895 0.1192
X2 -0.463512 0.278015 -1.667221 0.1049
X3 0.460748 0.335118 1.374883 0.1784
X4 0.764355 0.404579 1.889260 0.0677
RESID(-1) -0.976840 0.483637 -2.019780 0.0516
RESID(-2) -0.043800 0.198108 -0.221089 0.8264
R-squared 0.131220 Mean dependent var 2.33E-11
Adjusted R-squared -0.026740 S.D. dependent var 441142.2 S.E. of regression 447001.4 Akaike info criterion 29.01614 Sum squared resid 6.59E+12 Schwarz criterion 29.31169 Log likelihood -573.3228 Hannan-Quinn criter. 29.12300 F-statistic 0.830716 Durbin-Watson stat 1.881867 Prob(F-statistic) 0.554809
Lampiran 5. Hasil Uji Regresi Robust dengan E-Views 10 Dependent Variable: Y
Method: Robust Least Squares Date: 07/17/20 Time: 00:02 Sample: 1979 2018
Included observations: 40 Method: M-estimation
M settings: weight=Bisquare, tuning=4.685, scale=MAD (median centered) Huber Type I Standard Errors & Covariance
Variable Coefficient Std. Error z-Statistic Prob.
C -15220.98 310483.0 -0.049024 0.9609
X1 -40.41597 27.65855 -1.461247 0.1439
X2 0.826737 0.122707 6.737509 0.0000
X3 -0.869174 0.191603 -4.536337 0.0000
X4 0.422860 0.114192 3.703073 0.0002
Robust Statistics
R-squared 0.709701 Adjusted R-squared 0.676524
Rw-squared 0.946787 Adjust Rw-squared 0.946787
Akaike info criterion 42.21216 Schwarz criterion 54.23089
Deviance 4.67E+12 Scale 361347.7
Rn-squared statistic 472.3267 Prob(Rn-squared stat.) 0.000000 Non-robust Statistics
Mean dependent var 1301051. S.D. dependent var 1311418.
S.E. of regression 475915.6 Sum squared resid 7.93E+12
Lampiran 6. Hasil Analisis Forecasting atau Peramalan dengan E-Views dengan metode ARIMA (Ar-1)
Hasil Uji ARIMA (AR-1) Dependent Variable: D(Y)
Method: ARMA Maximum Likelihood (OPG - BHHH) Date: 07/17/20 Time: 09:41
Sample: 1980 2018 Included observations: 39
Convergence achieved after 23 iterations
Coefficient covariance computed using outer product of gradients
Variable Coefficient Std. Error t-Statistic Prob.
C 118391.8 64974.35 1.822131 0.0768
AR(1) -0.374993 0.138975 -2.698269 0.0105
SIGMASQ 2.68E+11 7.20E+10 3.715135 0.0007
R-squared 0.145721 Mean dependent var 121250.6
Adjusted R-squared 0.098261 S.D. dependent var 567075.4 S.E. of regression 538494.6 Akaike info criterion 29.30863 Sum squared resid 1.04E+13 Schwarz criterion 29.43660 Log likelihood -568.5183 Hannan-Quinn criter. 29.35454 F-statistic 3.070392 Durbin-Watson stat 1.874615 Prob(F-statistic) 0.058722
Inverted AR Roots -.37
Hasil Uji Correlogram of Residuals Date: 07/21/20 Time: 15:16
Sample: 1979 2025 Included observations: 39
Q-statistic probabilities adjusted for 1 ARMA term
Autocorrelation Partial Correlation AC PAC Q-Stat Prob . | . | . | . | 1 0.035 0.035 0.0510
. | . | . | . | 2 0.009 0.008 0.0544 0.816 **| . | **| . | 3 -0.295 -0.296 3.9290 0.140 . | . | . | . | 4 0.000 0.023 3.9290 0.269 . | . | . | . | 5 0.055 0.068 4.0708 0.397 . |** | . |** | 6 0.325 0.256 9.2014 0.101 . |*. | . |*. | 7 0.116 0.118 9.8747 0.130 . | . | . | . | 8 0.028 0.050 9.9150 0.193 **| . | .*| . | 9 -0.260 -0.141 13.512 0.095 .*| . | .*| . | 10 -0.111 -0.084 14.187 0.116 . |*. | . |*. | 11 0.154 0.175 15.548 0.113 . | . | .*| . | 12 0.018 -0.195 15.567 0.158 . | . | .*| . | 13 -0.043 -0.189 15.682 0.206 . | . | . | . | 14 -0.029 0.055 15.737 0.264 . | . | . |*. | 15 -0.014 0.082 15.750 0.329 .*| . | .*| . | 16 -0.089 -0.079 16.307 0.362