arima musiman
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c Farid Mochamad Afendi 2008 Powered by Powerdot of LATEX – 1 / 31
STK352
Analisis Deret Waktu
MODEL ARIMA MUSIMANPertemuan 12
Farid Mochamad AfendiDepartemen Statistika IPB
27 Mei 2008
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MATERI PEMBAHASAN
MATERIPEMBAHASAN
PENGANTAR
MODEL ARMAMUSIMAN
ILUSTRASI
c Farid Mochamad Afendi 2008 Powered by Powerdot of LATEX – 2 / 31
PENGANTAR
MODEL ARMA MUSIMAN
ILUSTRASI
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PENGANTAR
MATERIPEMBAHASAN
PENGANTAR
Pengantar
MODEL ARMAMUSIMAN
ILUSTRASI
c Farid Mochamad Afendi 2008 Powered by Powerdot of LATEX – 3 / 31
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Pengantar
MATERIPEMBAHASAN
PENGANTAR
Pengantar
MODEL ARMAMUSIMAN
ILUSTRASI
c Farid Mochamad Afendi 2008 Powered by Powerdot of LATEX – 4 / 31
Model ARIMA juga dapat digunakan untuk fitting data yangberpola musiman.
Langkah awal adalah penentuan s atau panjang periodemusiman.
Proses identifikasi model ARIMA musiman analog denganmodel ARIMA non musiman.
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MODEL ARMA MUSIMAN
MATERIPEMBAHASAN
PENGANTAR
MODEL ARMAMUSIMAN
Model MA(1) Musiman
Model MA(Q)Musiman
Model AR(1) Musiman
Model AR(P )
Musiman
ILUSTRASI
c Farid Mochamad Afendi 2008 Powered by Powerdot of LATEX – 5 / 31
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Model MA(1) Musiman
MATERIPEMBAHASAN
PENGANTAR
MODEL ARMAMUSIMAN
Model MA(1) Musiman
Model MA(Q)Musiman
Model AR(1) Musiman
Model AR(P )
Musiman
ILUSTRASI
c Farid Mochamad Afendi 2008 Powered by Powerdot of LATEX – 6 / 31
Bila periode musiman s = 12 maka model musiman MA(1)
Z t = at −ΘZ t−12
Mudah ditunjukkan bahwa series tersebut memiliki autokorelasitidak nol hanya untuk lag 12 saja.
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Model MA( Q ) Musiman
MATERIPEMBAHASAN
PENGANTAR
MODEL ARMAMUSIMAN
Model MA(1) Musiman
Model MA(Q)Musiman
Model AR(1) Musiman
Model AR(P )
Musiman
ILUSTRASI
c Farid Mochamad Afendi 2008 Powered by Powerdot of LATEX – 7 / 31
Secara umum, model musiman MA(Q) adalah
Z t = at −Θ1Z t−s −Θ2Z t−2s − . . .−ΘQZ t−Qs
dengan persamaan polinomial ciri MA musimannya
Θ(x) = 1−Θ1xs−Θ2x
2s− . . .−ΘQx
Qs
Model ini invertible bila nilai mutlak dari akar Θ(x) = 0semuanya lebih dari 1.
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Model MA( Q ) Musiman (lanjutan)
MATERIPEMBAHASAN
PENGANTAR
MODEL ARMAMUSIMAN
Model MA(1) Musiman
Model MA(Q)Musiman
Model AR(1) Musiman
Model AR(P )
Musiman
ILUSTRASI
c Farid Mochamad Afendi 2008 Powered by Powerdot of LATEX – 8 / 31
Seperti model MA(q ) non musiman, MA(Q) musiman memilikiautokorelasi yang tidak nol untuk lag s, 2s , . . . ,Qs.
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Model AR(1) Musiman
MATERIPEMBAHASAN
PENGANTAR
MODEL ARMAMUSIMAN
Model MA(1) Musiman
Model MA(Q)Musiman
Model AR(1) Musiman
Model AR(P )
Musiman
ILUSTRASI
c Farid Mochamad Afendi 2008 Powered by Powerdot of LATEX – 9 / 31
Untuk model AR(1) musiman masih dengan s = 12
Z t = ΦZ t−12 + at
Dapat ditunjukkan bahwa ρ12k = Φk untuk k = 1, 2, . . . denganautokorelasi lag lain bernilai 0.
Dengan kata lain, autokorelasi kelipatan periode musimanadalah tail off sementara autokorelasi lag lain bernilai nol.
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Model AR( P ) Musiman
MATERIPEMBAHASAN
PENGANTAR
MODEL ARMAMUSIMAN
Model MA(1) Musiman
Model MA(Q)
Musiman
Model AR(1) Musiman
Model AR(P )
Musiman
ILUSTRASI
c Farid Mochamad Afendi 2008 Powered by Powerdot of LATEX – 10 / 31
Secara umum, model AR(P ) musiman adalah
Z t = Φ1Z t−s + Φ2Z t−2s + . . . + ΦP Z t−Ps + at
dengan persamaan polinomial ciri AR musimannya
Φ(x) = 1− Φ1xs− Φ2x
2s− . . .− ΦP x
Ps
Model ini stasioner bila nilai mutlak dari akar Φ(x) = 0semuanya lebih dari 1.
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Model AR( P ) Musiman (lanjutan)
MATERIPEMBAHASAN
PENGANTAR
MODEL ARMAMUSIMAN
Model MA(1) Musiman
Model MA(Q)
Musiman
Model AR(1) Musiman
Model AR(P )
Musiman
ILUSTRASI
c Farid Mochamad Afendi 2008 Powered by Powerdot of LATEX – 11 / 31
Model AR(P ) musiman memiliki
autokorelasi kelipatan periode musiman tail off sementaraautokorelasi lag lain bernilai nol.
autokorelasi parsial cut off setelah lag P kelipatan periode
musiman, sementara lag lain bernilai nol.
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ILUSTRASI
MATERIPEMBAHASAN
PENGANTAR
MODEL ARMAMUSIMAN
ILUSTRASI
U.S. Air PassengerData
Plot Data Asal
Plot Transformasi Ln
PemeriksanKehomogenan Ragam
ACF DataTransformasi Ln
ACF Musiman DataTransformasi Ln
diff 1
Diff 12
diff 1-Diff 12
Fitting
Diagnosa
Validasi
c Farid Mochamad Afendi 2008 Powered by Powerdot of LATEX – 12 / 31
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U.S. Air Passenger Data
MATERIPEMBAHASAN
PENGANTAR
MODEL ARMAMUSIMAN
ILUSTRASI
U.S. Air PassengerData
Plot Data Asal
Plot Transformasi Ln
PemeriksanKehomogenan Ragam
ACF DataTransformasi Ln
ACF Musiman DataTransformasi Ln
diff 1
Diff 12
diff 1-Diff 12
Fitting
Diagnosa
Validasi
c Farid Mochamad Afendi 2008 Powered by Powerdot of LATEX – 13 / 31
Sebagai ilustrasi, disajikan analisis data ’U.S. Air PassengerData’ yang berupa data bulanan dari Januari 1960 hinggaDesember 1977 (Cryer, 1986 p.270).
Data tahun terakhir digunakan untuk validasi
2.42 2.14 2.28 2.50 2.44 2.72 2.71 2.74 2.55 2.49 2.13 2.28 # 1962.35 1.82 2.40 2.46 2.38 2.83 2.68 2.81 2.54 2.54 2.37 2.54 # 1962.62 2.34 2.68 2.75 2.66 2.96 2.66 2.93 2.70 2.65 2.46 2.59 # 196
2.75 2.45 2.85 2.99 2.89 3.43 3.25 3.59 3.12 3.16 2.86 3.22 # 1963.24 2.95 3.32 3.29 3.32 3.91 3.80 4.02 3.53 3.61 3.22 3.67 # 1963.75 3.25 3.70 3.98 3.88 4.47 4.60 4.90 4.20 4.20 3.80 4.50 # 1964.40 4.00 4.70 5.10 4.90 5.70 3.90 4.20 5.10 5.00 4.70 5.50 # 1965.30 4.60 5.90 5.50 5.40 6.70 6.80 7.40 6.00 5.80 5.50 6.40 # 1966.20 5.70 6.40 6.70 6.30 7.80 7.60 8.60 6.60 6.50 6.00 7.60 # 196
7.00 6.00 7.10 7.40 7.20 8.40 8.50 9.40 7.10 7.00 6.60 8.00 # 19610.45 8.81 10.61 9.97 10.69 12.40 13.38 14.31 10.90 9.98 9.20 10.94 # 19710.53 9.06 10.17 11.17 10.84 12.09 13.66 14.06 11.14 11.10 10.00 11.98 # 19711.74 10.27 12.05 12.27 12.03 13.95 15.10 15.65 12.47 12.29 11.52 13.08 # 19712.50 11.05 12.94 13.24 13.16 14.95 16.00 16.98 13.15 12.88 11.99 13.13 # 19712.99 11.69 13.78 13.70 13.57 15.12 15.55 16.73 12.68 12.65 11.18 13.27 # 19712.64 11.01 13.30 12.19 12.91 14.90 16.10 17.30 12.90 13.36 12.26 13.93 # 19713.94 12.75 14.19 14.67 14.66 16.21 17.72 18.15 14.19 14.33 12.99 15.19 # 197
15.09 12.94 15.46 15.39 15.34 17.02 18.85 19.49 15.61 16.16 14.84 17.04 # 197
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Plot Data Asal
MATERIPEMBAHASAN
PENGANTAR
MODEL ARMAMUSIMAN
ILUSTRASI
U.S. Air PassengerData
Plot Data Asal
Plot Transformasi Ln
PemeriksanKehomogenan Ragam
ACF DataTransformasi Ln
ACF Musiman DataTransformasi Ln
diff 1
Diff 12
diff 1-Diff 12
Fitting
Diagnosa
Validasi
c Farid Mochamad Afendi 2008 Powered by Powerdot of LATEX – 14 / 31
Plot data asal memperlihatkan pola musiman dengan s = 12 sertaadanya perilaku nonstasioner baik dalam rataan maupun ragam.
Gambar 1: Time Series Plot Data Asal
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Plot Transformasi Ln
MATERIPEMBAHASAN
PENGANTAR
MODEL ARMAMUSIMAN
ILUSTRASI
U.S. Air PassengerData
Plot Data Asal
Plot Transformasi Ln
PemeriksanKehomogenan Ragam
ACF DataTransformasi Ln
ACF Musiman DataTransformasi Ln
diff 1
Diff 12
diff 1-Diff 12
Fitting
Diagnosa
Validasi
c Farid Mochamad Afendi 2008 Powered by Powerdot of LATEX – 15 / 31
Transformasi logaritma berhasil mengatasi ketidakstasionerandalam ragam meskipun ketidakstasioneran dalam rataan masihnampak.
Gambar 2: Time Series Plot Data Transformasi Logaritma
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Pemeriksan Kehomogenan Ragam
MATERIPEMBAHASAN
PENGANTAR
MODEL ARMAMUSIMAN
ILUSTRASI
U.S. Air PassengerData
Plot Data Asal
Plot Transformasi Ln
PemeriksanKehomogenan Ragam
ACF DataTransformasi Ln
ACF Musiman DataTransformasi Ln
diff 1
Diff 12
diff 1-Diff 12
Fitting
Diagnosa
Validasi
c Farid Mochamad Afendi 2008 Powered by Powerdot of LATEX – 16 / 31
Gambar 3: Plot Range-Mean data asal
Gambar 4: Plot Range-Mean data transformasi ln
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Pemeriksan Kehomogenan Ragam (lanjutan)
MATERIPEMBAHASAN
PENGANTAR
MODEL ARMAMUSIMAN
ILUSTRASI
U.S. Air PassengerData
Plot Data Asal
Plot Transformasi Ln
PemeriksanKehomogenan Ragam
ACF DataTransformasi Ln
ACF Musiman DataTransformasi Ln
diff 1
Diff 12
diff 1-Diff 12
Fitting
Diagnosa
Validasi
c Farid Mochamad Afendi 2008 Powered by Powerdot of LATEX – 17 / 31
Gambar 5: Uji kehomogenan ragam data asal
Gambar 6: Uji kehomogenan ragam data transformasi ln
ACF D T f i L23:49:27
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ACF Data Transformasi Ln
MATERIPEMBAHASAN
PENGANTAR
MODEL ARMAMUSIMAN
ILUSTRASI
U.S. Air PassengerData
Plot Data Asal
Plot Transformasi Ln
PemeriksanKehomogenan Ragam
ACF DataTransformasi Ln
ACF Musiman DataTransformasi Ln
diff 1
Diff 12
diff 1-Diff 12
Fitting
Diagnosa
Validasi
c Farid Mochamad Afendi 2008 Powered by Powerdot of LATEX – 18 / 31
Plot ACF data setelah transformasi logaritma menunjukkan polanonstasioner. Perhatikan juga pola ACF untuk lag s, 2s , . . ..
Gambar 7: Plot ACF Data Transformasi Logaritma
ACF M i D t T f i L23:49:27
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ACF Musiman Data Transformasi Ln
MATERIPEMBAHASAN
PENGANTAR
MODEL ARMAMUSIMAN
ILUSTRASI
U.S. Air PassengerData
Plot Data Asal
Plot Transformasi Ln
PemeriksanKehomogenan Ragam
ACF DataTransformasi Ln
ACF Musiman DataTransformasi Ln
diff 1
Diff 12
diff 1-Diff 12
Fitting
Diagnosa
Validasi
c Farid Mochamad Afendi 2008 Powered by Powerdot of LATEX – 19 / 31
Plot ACF data setelah transformasi logaritma untuk lag 12, 24, 36,48 menunjukkan pola nonstasioner.
Gambar 8: Plot ACF Musiman Data Transformasi Logaritma
Pl t D t N l Diff i d 123:49:27
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Plot Data Nonseasonal Differencing d = 1
MATERIPEMBAHASAN
PENGANTAR
MODEL ARMAMUSIMAN
ILUSTRASI
U.S. Air PassengerData
Plot Data Asal
Plot Transformasi Ln
PemeriksanKehomogenan Ragam
ACF DataTransformasi Ln
ACF Musiman DataTransformasi Ln
diff 1
Diff 12
diff 1-Diff 12
Fitting
Diagnosa
Validasi
c Farid Mochamad Afendi 2008 Powered by Powerdot of LATEX – 20 / 31
Nonseasonal differencing d = 1 berhasil mengatasiketidakstasioneran dalam rataan untuk komponen nonseasonalnya.
Gambar 9: Plot data setelah nonseasonal differencing d = 1
Plot ACF Data Nonseasonal Differencing23:49:27
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Plot ACF Data Nonseasonal Differencing
d = 1
MATERIPEMBAHASAN
PENGANTAR
MODEL ARMAMUSIMAN
ILUSTRASI
U.S. Air PassengerData
Plot Data Asal
Plot Transformasi Ln
PemeriksanKehomogenan Ragam
ACF DataTransformasi Ln
ACF Musiman DataTransformasi Ln
diff 1
Diff 12
diff 1-Diff 12
Fitting
Diagnosa
Validasi
c Farid Mochamad Afendi 2008 Powered by Powerdot of LATEX – 21 / 31
Plot ACF data nonseasonal differencing d = 1 mengkonfirmasikestasioneran komponen non musiman (namun perhatikan lag 12,24, dst).
(a)
Plot ACF
(b)
Plot ACF Musiman
Gambar 10: Plot ACF Data Nonseasonal Differencing d = 1
Plot Data Seasonal Differencing D 1223:49:27
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Plot Data Seasonal Differencing D = 12
MATERIPEMBAHASAN
PENGANTAR
MODEL ARMAMUSIMAN
ILUSTRASI
U.S. Air PassengerData
Plot Data Asal
Plot Transformasi Ln
PemeriksanKehomogenan Ragam
ACF DataTransformasi Ln
ACF Musiman DataTransformasi Ln
diff 1
Diff 12
diff 1-Diff 12
Fitting
Diagnosa
Validasi
c Farid Mochamad Afendi 2008 Powered by Powerdot of LATEX – 22 / 31
Gambar 11: Plot data setelah seasonal differencing D = 12
Plot ACF Data Seasonal Differencing D 1223:49:27
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Plot ACF Data Seasonal Differencing D = 12
MATERIPEMBAHASAN
PENGANTAR
MODEL ARMAMUSIMAN
ILUSTRASI
U.S. Air PassengerData
Plot Data Asal
Plot Transformasi Ln
PemeriksanKehomogenan Ragam
ACF DataTransformasi Ln
ACF Musiman DataTransformasi Ln
diff 1
Diff 12
diff 1-Diff 12
Fitting
Diagnosa
Validasi
c Farid Mochamad Afendi 2008 Powered by Powerdot of LATEX – 23 / 31
Nonseasonal differencing D = 12 berhasil mengatasiketidakstasioneran dalam rataan untuk komponen seasonalnya(namun tidak untuk komponen non musimannya).
(a)
Plot ACF
(b)
Plot ACF Musiman
Gambar 12: Plot ACF data seasonal differencing D = 12
Plot Data Differencing d 1 D 1223:49:27
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Plot Data Differencing d = 1, D = 12
MATERIPEMBAHASAN
PENGANTAR
MODEL ARMAMUSIMAN
ILUSTRASI
U.S. Air PassengerData
Plot Data Asal
Plot Transformasi Ln
PemeriksanKehomogenan Ragam
ACF DataTransformasi Ln
ACF Musiman DataTransformasi Ln
diff 1
Diff 12
diff 1-Diff 12
Fitting
Diagnosa
Validasi
c Farid Mochamad Afendi 2008 Powered by Powerdot of LATEX – 24 / 31
Gambar 13: Plot data setelah differencing d = 1, D = 12
Plot ACF-PACF Data Differencing 23:49:27
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g
d = 1, D = 12
MATERIPEMBAHASAN
PENGANTAR
MODEL ARMAMUSIMAN
ILUSTRASI
U.S. Air PassengerData
Plot Data Asal
Plot Transformasi Ln
PemeriksanKehomogenan Ragam
ACF DataTransformasi Ln
ACF Musiman DataTransformasi Ln
diff 1
Diff 12
diff 1-Diff 12
Fitting
Diagnosa
Validasi
c Farid Mochamad Afendi 2008 Powered by Powerdot of LATEX – 25 / 31
Kedua komponen telah stasioner. Identifikasi komponen nonmusiman adalah ARIMA(0,1,2).
(a)Plot ACF
(b)Plot PACF
Gambar 14: Identifikasi ARIMA komponen non musiman
Plot ACF-PACF Musiman Data Differencing 23:49:27
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d = 1, D = 12
MATERIPEMBAHASAN
PENGANTAR
MODEL ARMAMUSIMAN
ILUSTRASI
U.S. Air PassengerData
Plot Data Asal
Plot Transformasi Ln
PemeriksanKehomogenan Ragam
ACF DataTransformasi Ln
ACF Musiman DataTransformasi Ln
diff 1
Diff 12
diff 1-Diff 12
Fitting
Diagnosa
Validasi
c Farid Mochamad Afendi 2008 Powered by Powerdot of LATEX – 26 / 31
Identifikasi komponen musiman adalah ARIMA(0,1,1)12, sehinggamodel tentatif adalah ARIMA(0,1,2)×(0,1,1)12.
(a)Plot ACF Musiman
(b)Plot PACF Musiman
Gambar 15: Identifikasi ARIMA komponen musiman
Fitting ARIMA(0 1 2)×(0 1 1)1223:49:27
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Fitting ARIMA(0,1,2) ×(0,1,1)12
MATERIPEMBAHASAN
PENGANTAR
MODEL ARMAMUSIMAN
ILUSTRASI
U.S. Air Passenger
Data
Plot Data Asal
Plot Transformasi Ln
PemeriksanKehomogenan Ragam
ACF DataTransformasi Ln
ACF Musiman DataTransformasi Ln
diff 1
Diff 12
diff 1-Diff 12
Fitting
Diagnosa
Validasi
c Farid Mochamad Afendi 2008 Powered by Powerdot of LATEX – 27 / 31
Pengepasan model (Fitting ) ARIMA(0,1,2)×(0,1,1)12
Gambar 16: Fitting ARIMA(0,1,2)×(0,1,1)12
Plot ACF-PACF Residual23:49:27
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Plot ACF PACF Residual
MATERIPEMBAHASAN
PENGANTAR
MODEL ARMAMUSIMAN
ILUSTRASI
U.S. Air Passenger
Data
Plot Data Asal
Plot Transformasi Ln
PemeriksanKehomogenan Ragam
ACF DataTransformasi Ln
ACF Musiman DataTransformasi Ln
diff 1
Diff 12
diff 1-Diff 12
Fitting
Diagnosa
Validasi
c Farid Mochamad Afendi 2008 Powered by Powerdot of LATEX – 28 / 31
Identifikasi komponen musiman adalah ARIMA(0,1,1)12, sehinggamodel tentatif adalah ARIMA(0,1,2)×(0,1,1)12.
(a)Plot ACF Residual
(b)Plot PACF Residual
Gambar 17: Plot ACF-PACF residual
Diagnosa Model23:49:27
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Diagnosa Model
MATERIPEMBAHASAN
PENGANTAR
MODEL ARMAMUSIMAN
ILUSTRASI
U.S. Air Passenger
Data
Plot Data Asal
Plot Transformasi Ln
PemeriksanKehomogenan Ragam
ACF DataTransformasi Ln
ACF Musiman DataTransformasi Ln
diff 1
Diff 12
diff 1-Diff 12
Fitting
Diagnosa
Validasi
c Farid Mochamad Afendi 2008 Powered by Powerdot of LATEX – 29 / 31
Diagnosa model dari plot residual
Gambar 18: Diagnosa model dari plot residual
Validasi Model23:49:27
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Validasi Model
MATERIPEMBAHASAN
PENGANTAR
MODEL ARMAMUSIMAN
ILUSTRASI
U.S. Air Passenger
Data
Plot Data Asal
Plot Transformasi Ln
PemeriksanKehomogenan Ragam
ACF DataTransformasi Ln
ACF Musiman DataTransformasi Ln
diff 1
Diff 12
diff 1-Diff 12
Fitting
Diagnosa
Validasi
c Farid Mochamad Afendi 2008 Powered by Powerdot of LATEX – 30 / 31
Validasi Model menggunakan data Tahun 1977: (MAD=0.344 danMAPE=2.14%)
Gambar 19: Validasi Model dari data Tahun 1997
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MATERIPEMBAHASAN
PENGANTAR
MODEL ARMAMUSIMAN
ILUSTRASI
U.S. Air Passenger
Data
Plot Data Asal
Plot Transformasi Ln
PemeriksanKehomogenan Ragam
ACF DataTransformasi Ln
ACF Musiman DataTransformasi Ln
diff 1
Diff 12
diff 1-Diff 12
Fitting
Diagnosa
Validasi
c Farid Mochamad Afendi 2008 Powered by Powerdot of LATEX – 31 / 31
TERIMA KASIH