ๅๆฃใทในใใ ่ชญๆธไผ 13็ซ -ๅๆฃๅ่ชฟใใผในใทในใใ
[1] 2 AR(1) (3.5)tyabu/enders/solutions_ch3.pdfย ยท 2019-11-05ย ยท ๐ธ๐ธ[๐๐. ๐ก๐ก2] =...
Transcript of [1] 2 AR(1) (3.5)tyabu/enders/solutions_ch3.pdfย ยท 2019-11-05ย ยท ๐ธ๐ธ[๐๐. ๐ก๐ก2] =...
![Page 1: [1] 2 AR(1) (3.5)tyabu/enders/solutions_ch3.pdfย ยท 2019-11-05ย ยท ๐ธ๐ธ[๐๐. ๐ก๐ก2] = ๐ผ๐ผ. 0. 1 โโ ๐ผ๐ผ. ๐๐ ๐๐ ๐๐=1. ใๅพใใไปฅไธใใใๆกไปถใชใๅนณๅใๅๆฃใ่ชๅทฑๅ
ฑๅๆฃใฏๆ็นใซไพๅญใใฆใใชใใใใ](https://reader035.fdocuments.net/reader035/viewer/2022062915/5e97b8f0deafcd264728dc62/html5/thumbnails/1.jpg)
2019/11/05
ๆฐ่ฐทๅ ๅฃใ่ชๅ่ฏ
็ฌฌ 3 ็ซ ใฎ่งฃ็ญ [1] ๅฅใฎ่งฃๆณใจใใฆใ2 ็ซ ใง AR(1)้็จใฎๆกไปถใชใๅนณๅใๅฐๅบใใๆนๆณใงใ(3.5)ๅผใๅฐๅบใง
ใใใใพใใ
๐ธ๐ธ[๐๐๐ก๐ก2] = ๐ผ๐ผ0 + ๐ผ๐ผ1๐ธ๐ธ[๐๐๐ก๐กโ12 ]
ใซใ๐ธ๐ธ[๐๐๐ก๐กโ12 ] = ๐ผ๐ผ0 + ๐ผ๐ผ1๐ธ๐ธ[๐๐๐ก๐กโ22 ]ใไปฃๅ ฅใใใจใ
๐ธ๐ธ[๐๐๐ก๐ก2] = ๐ผ๐ผ0 + ๐ผ๐ผ1(๐ผ๐ผ0 + ๐ผ๐ผ1๐ธ๐ธ[๐๐๐ก๐กโ22 ])
= ๐ผ๐ผ0(1 + ๐ผ๐ผ1) + ๐ผ๐ผ12 ๐ธ๐ธ[๐๐๐ก๐กโ22 ]
ใจใชใใใใใซไปฃๅ ฅใ็นฐใ่ฟใใจใ
๐ธ๐ธ[๐๐๐ก๐ก2] = ๐ผ๐ผ0(1 + ๐ผ๐ผ1 + ๐ผ๐ผ12 โฆ + ๐ผ๐ผ1๐ก๐กโ1) + ๐ผ๐ผ1๐ก๐ก ๐ธ๐ธ[๐๐02]
ใๅพใใใใใง|๐ผ๐ผ1| < 1ใงใใใใใ๐ก๐กใๅๅใซๅคงใใใชใใจใ๐ผ๐ผ0(1 + ๐ผ๐ผ1 + ๐ผ๐ผ12 โฆ + ๐ผ๐ผ1๐ก๐กโ1)ใฏ
๐ผ๐ผ0/(1โ ๐ผ๐ผ1)ใซใ๐ผ๐ผ1๐ก๐ก ๐ธ๐ธ[๐๐02]ใฏ 0 ใซๅๆใใฆใใใใใใใฃใฆใ๐ก๐กใๅๅใซๅคงใใใจใ
๐ธ๐ธ[๐๐๐ก๐ก2] =๐ผ๐ผ0
1 โ ๐ผ๐ผ1
[2] ARCH(1)้็จใซใใใฆใ๐๐๐ก๐กใฎๆกไปถใชใๅนณๅใฏใ
๐ธ๐ธ[๐๐๐ก๐ก] = ๐ธ๐ธ ๏ฟฝ๐ฃ๐ฃ๐ก๐ก ๏ฟฝ๐ผ๐ผ0 +๏ฟฝ ๐ผ๐ผ๐๐๐๐๐ก๐กโ๐๐2๐๐
๐๐=1๏ฟฝ
12๏ฟฝ
= ๐ธ๐ธ[๐ฃ๐ฃ๐ก๐ก]๐ธ๐ธ ๏ฟฝ๏ฟฝ๐ผ๐ผ0 + ๏ฟฝ ๐ผ๐ผ๐๐๐๐๐ก๐กโ๐๐2๐๐
๐๐=1๏ฟฝ
12๏ฟฝ = 0
ใจใชใ๏ผ๐ฃ๐ฃ๐ก๐กใจ๐๐๐ก๐กโ๐๐ใฎ็ฌ็ซๆงใซๆณจๆ๏ผใ่ชๅทฑๅ ฑๅๆฃใฏ๏ผ๐๐ โ 0ใซๅฏพใ๏ผ
๐ธ๐ธ[๐๐๐ก๐ก๐๐๐ก๐กโ๐๐] = ๐ธ๐ธ ๏ฟฝ๐ฃ๐ฃ๐ก๐ก๐ฃ๐ฃ๐ก๐กโ๐๐ ๏ฟฝ๐ผ๐ผ0 + ๏ฟฝ ๐ผ๐ผ๐๐๐๐๐ก๐กโ๐๐2๐๐
๐๐=1๏ฟฝ
12๏ฟฝ๐ผ๐ผ0 + ๏ฟฝ ๐ผ๐ผ๐๐๐๐๐ก๐กโ๐๐โ๐๐2
๐๐
๐๐=1๏ฟฝ
12๏ฟฝ
= ๐ธ๐ธ[๐ฃ๐ฃ๐ก๐ก]๐ธ๐ธ ๏ฟฝ๐ฃ๐ฃ๐ก๐กโ๐๐ ๏ฟฝ๐ผ๐ผ0 + ๏ฟฝ ๐ผ๐ผ๐๐๐๐๐ก๐กโ๐๐2๐๐
๐๐=1๏ฟฝ
12๏ฟฝ๐ผ๐ผ0 + ๏ฟฝ ๐ผ๐ผ๐๐๐๐๐ก๐กโ๐๐โ๐๐2
๐๐
๐๐=1๏ฟฝ
12๏ฟฝ = 0
ใจใชใใใพใใ๐๐๐ก๐กใฎๆกไปถใชใๅๆฃใฏ
๐ธ๐ธ[๐๐๐ก๐ก2] = ๐ธ๐ธ ๏ฟฝ๐ฃ๐ฃ๐ก๐ก2 ๏ฟฝ๐ผ๐ผ0 + ๏ฟฝ ๐ผ๐ผ๐๐๐๐๐ก๐กโ๐๐2๐๐
๐๐=1๏ฟฝ๏ฟฝ
= ๐ผ๐ผ0 + ๏ฟฝ ๐ผ๐ผ๐๐๐ธ๐ธ[๐๐๐ก๐กโ๐๐2 ]๐๐
๐๐=1
ใจใชใใใใใง๐ธ๐ธ[๐๐๐ก๐ก2] = ๐ธ๐ธ[๐๐๐ก๐กโ๐๐2 ]ใ็จใใฆใไธๅผใ๐ธ๐ธ[๐๐๐ก๐ก2]ใซใคใใฆ่งฃใใฐ
![Page 2: [1] 2 AR(1) (3.5)tyabu/enders/solutions_ch3.pdfย ยท 2019-11-05ย ยท ๐ธ๐ธ[๐๐. ๐ก๐ก2] = ๐ผ๐ผ. 0. 1 โโ ๐ผ๐ผ. ๐๐ ๐๐ ๐๐=1. ใๅพใใไปฅไธใใใๆกไปถใชใๅนณๅใๅๆฃใ่ชๅทฑๅ
ฑๅๆฃใฏๆ็นใซไพๅญใใฆใใชใใใใ](https://reader035.fdocuments.net/reader035/viewer/2022062915/5e97b8f0deafcd264728dc62/html5/thumbnails/2.jpg)
๐ธ๐ธ[๐๐๐ก๐ก2] =๐ผ๐ผ0
1 โ โ ๐ผ๐ผ๐๐๐๐๐๐=1
ใๅพใใไปฅไธใใใๆกไปถใชใๅนณๅใๅๆฃใ่ชๅทฑๅ ฑๅๆฃใฏๆ็นใซไพๅญใใฆใใชใใใใ{๐๐๐ก๐ก}ใฏ
ๅฎๅธธใงใใใ
ๆฌกใซใๆกไปถไปใๅนณๅใจๅๆฃใๆฑใใฆใฟใใใ๐ก๐ก โ 1ๆใพใงใฎๆ ๅ ฑใๆไธใจใใใจใ๐๐๐ก๐กใฎๆกไปถ
ไปใๅนณๅใฏใ
๐ธ๐ธ[๐๐๐ก๐ก|๐๐๐ก๐กโ1, ๐๐๐ก๐กโ2, โฆ ] = ๐ธ๐ธ๐ก๐กโ1๐ฃ๐ฃ๐ก๐ก ๐ธ๐ธ๐ก๐กโ1 ๏ฟฝ๏ฟฝ๐ผ๐ผ0 + ๏ฟฝ ๐ผ๐ผ๐๐๐๐๐ก๐กโ๐๐2๐๐
๐๐=1๏ฟฝ
12๏ฟฝ = 0
ใจใชใใ๐ก๐ก โ 1ๆใพใงใฎๆ ๅ ฑใๆไธใจใใใจใ๐๐๐ก๐กใฎๆกไปถไปใๅๆฃใฏใ
๐ธ๐ธ[๐๐๐ก๐ก2|๐๐๐ก๐กโ1, ๐๐๐ก๐กโ2, โฆ ] = ๐ธ๐ธ๐ก๐กโ1๐ฃ๐ฃ๐ก๐ก2 ๐ธ๐ธ๐ก๐กโ1 ๏ฟฝ๏ฟฝ๐ผ๐ผ0 + ๏ฟฝ ๐ผ๐ผ๐๐๐๐๐ก๐กโ๐๐2๐๐
๐๐=1๏ฟฝ๏ฟฝ
= ๐ผ๐ผ0 + ๏ฟฝ ๐ผ๐ผ๐๐๐๐๐ก๐กโ๐๐2๐๐
๐๐=1
ๅผๅฑ้ใงใฏใฯv2=1ใ๐ฃ๐ฃ๐ก๐กใจ๐๐๐ก๐กโ๐๐ใฏไบใใซ็ฌ็ซใงใใใใจใซๆณจๆใไปฅไธใใใๆกไปถไปใๅๆฃใฏใ
๐๐๐ก๐กโ๐๐2 ใฎๅฎ็พๅคใซไพๅญใใใ
[3] GARCH(1,1)้็จ
โ๐ก๐ก = ๐ผ๐ผ0 + ๐ผ๐ผ1๐๐๐ก๐กโ12 + ๐ฝ๐ฝ1โ๐ก๐กโ1
ใ่ใใใใใฎใจใใใใฎๅผใซ 1 ๆๅใฎๆกไปถไปใๅๆฃโ๐ก๐กโ1 = ๐ผ๐ผ0 + ๐ผ๐ผ1๐๐๐ก๐กโ22 + ๐ฝ๐ฝ1โ๐ก๐กโ2ใไปฃๅ ฅใ
ใใจใ
โ๐ก๐ก = ๐ผ๐ผ0 + ๐ผ๐ผ1๐๐๐ก๐กโ12 + ๐ฝ๐ฝ1(๐ผ๐ผ0 + ๐ผ๐ผ1๐๐๐ก๐กโ22 + ๐ฝ๐ฝ1โ๐ก๐กโ2)
= ๐ผ๐ผ0(1 + ๐ฝ๐ฝ1) + ๐ผ๐ผ1๐๐๐ก๐กโ12 + ๐ผ๐ผ1๐ฝ๐ฝ1๐๐๐ก๐กโ22 + ๐ฝ๐ฝ12โ๐ก๐กโ2
ใจใชใใใใใซ 2 ๆๅใฎๆกไปถไปใๅๆฃโ๐ก๐กโ2 = ๐ผ๐ผ0 + ๐ผ๐ผ1๐๐๐ก๐กโ32 + ๐ฝ๐ฝ1โ๐ก๐กโ3ใไปฃๅ ฅใใใจใ
โ๐ก๐ก = ๐ผ๐ผ0(1 + ๐ฝ๐ฝ1) + ๐ผ๐ผ1๐๐๐ก๐กโ12 + ๐ผ๐ผ1๐ฝ๐ฝ1๐๐๐ก๐กโ22 + ๐ฝ๐ฝ12(๐ผ๐ผ0 + ๐ผ๐ผ1๐๐๐ก๐กโ32 + ๐ฝ๐ฝ1โ๐ก๐กโ3)
= ๐ผ๐ผ0(1 + ๐ฝ๐ฝ1 + ๐ฝ๐ฝ12) + ๐ผ๐ผ1๐๐๐ก๐กโ12 + ๐ผ๐ผ1๐ฝ๐ฝ1๐๐๐ก๐กโ22 + ๐ผ๐ผ1๐ฝ๐ฝ12๐๐๐ก๐กโ32 + ๐ฝ๐ฝ13โ๐ก๐กโ3 ใจใชใใใใใใไปฃๅ ฅใ็นฐใ่ฟใใฆใใใจใhtใฏ ARCH(โ)้็จใจใใฆ่กจใใใ
โ๐ก๐ก = ๐ผ๐ผ0(1 + ๐ฝ๐ฝ1 + ๐ฝ๐ฝ12+. . . ) + ๐ผ๐ผ1๐๐๐ก๐กโ12 + ๐ผ๐ผ1๐ฝ๐ฝ1๐๐๐ก๐กโ22 + ๐ผ๐ผ1๐ฝ๐ฝ12๐๐๐ก๐กโ32 +. ..
ใใใง|๐ฝ๐ฝ1| < 1ใงใใใใ(๐ผ๐ผ1 > 0,๐ฝ๐ฝ1 โฅ0ใ๐ผ๐ผ1 + ๐ฝ๐ฝ1 < 1ใใใ1 > ๐ฝ๐ฝ1 โฅ0)ใ๐๐ใ้ๅธธใซๅคงใใใช
ใ๐ฝ๐ฝ1๐๐โ๐ก๐กโ๐๐ใฏ 0 ใจใชใใใจใซๆณจๆใ
[4] ไบๆธฌ่ชคๅทฎใ
๐ข๐ข๐ก๐ก = ๐๐๐ก๐ก2 โ ๐ธ๐ธ๐ก๐กโ1๐๐๐ก๐ก2 = ๐๐๐ก๐ก2 โ โ๐ก๐ก
ใจๅฎ็พฉใใใGARCH(1, 2)้็จโ๐ก๐ก = ๐ผ๐ผ0 + ๐ผ๐ผ1๐๐๐ก๐กโ12 + ๐ผ๐ผ2๐๐๐ก๐กโ22 + ๐ฝ๐ฝ1โ๐ก๐กโ1ใฎไธก่พบใซใไบๆธฌ่ชคๅทฎ๐ข๐ข๐ก๐ก =
๐๐๐ก๐ก2 โ โ๐ก๐กใๅ ใใใจ
![Page 3: [1] 2 AR(1) (3.5)tyabu/enders/solutions_ch3.pdfย ยท 2019-11-05ย ยท ๐ธ๐ธ[๐๐. ๐ก๐ก2] = ๐ผ๐ผ. 0. 1 โโ ๐ผ๐ผ. ๐๐ ๐๐ ๐๐=1. ใๅพใใไปฅไธใใใๆกไปถใชใๅนณๅใๅๆฃใ่ชๅทฑๅ
ฑๅๆฃใฏๆ็นใซไพๅญใใฆใใชใใใใ](https://reader035.fdocuments.net/reader035/viewer/2022062915/5e97b8f0deafcd264728dc62/html5/thumbnails/3.jpg)
โ๐ก๐ก + (๐๐๐ก๐ก2 โ โ๐ก๐ก) = ๐ผ๐ผ0 + ๐ผ๐ผ1๐๐๐ก๐กโ12 + ๐ผ๐ผ2๐๐๐ก๐กโ22 + ๐ฝ๐ฝ1โ๐ก๐กโ1 + (๐๐๐ก๐ก2 โ โ๐ก๐ก)
ใจใชใใๅทฆ่พบใๆด็ใใใจใ
๐๐๐ก๐ก2 = ๐ผ๐ผ0 + ๐ผ๐ผ1๐๐๐ก๐กโ12 + ๐ผ๐ผ2๐๐๐ก๐กโ22 + ๐ฝ๐ฝ1โ๐ก๐กโ1 + (๐๐๐ก๐ก2 โ โ๐ก๐ก)
ใจใชใใใใใงๅณ่พบใซ๐ฝ๐ฝ1๐๐๐ก๐กโ12 โ ๐ฝ๐ฝ1๐๐๐ก๐กโ12 ใๅ ใใใจ
๐๐๐ก๐ก2 = ๐ผ๐ผ0 + (๐ผ๐ผ1 + ๐ฝ๐ฝ1)๐๐๐ก๐กโ12 + ๐ผ๐ผ2๐๐๐ก๐กโ22 โ ๐ฝ๐ฝ1(๐๐๐ก๐กโ12 โ โ๐ก๐กโ1) + (๐๐๐ก๐ก2 โ โ๐ก๐ก)
ใจใชใใใใใง๐ข๐ข๐ก๐ก = ๐๐๐ก๐ก2 โ โ๐ก๐ก, ๐ข๐ข๐ก๐กโ1 = ๐๐๐ก๐กโ12 โ โ๐ก๐กโ1ใ็จใใใจ
๐๐๐ก๐ก2 = ๐ผ๐ผ0 + (๐ผ๐ผ1 + ๐ฝ๐ฝ1)๐๐๐ก๐กโ12 + ๐ผ๐ผ2๐๐๐ก๐กโ22 โ ๐ฝ๐ฝ1๐ข๐ข๐ก๐กโ1 + ๐ข๐ข๐ก๐ก
ใจใชใใ
(a) ใพใใฏ๐ข๐ข๐ก๐กใซ็ณปๅ็ธ้ขใใชใใใจใ็คบใใใคใพใใ๐ก๐ก โ ๐ ๐ ใฎใจใ
๐๐๐๐๐ฃ๐ฃ(๐ข๐ข๐ก๐ก ,๐ข๐ข๐ ๐ ) = 0
ใๆ็ซใใใใจใ็คบใใฐใใใๅฎ็พฉใซใใใ๐ข๐ข๐ก๐ก = ๐๐๐ก๐ก2 โ โ๐ก๐กใ๐๐๐ก๐ก = ๐ฃ๐ฃ๐ก๐กโ๐ก๐ก1/2
ใงใใใใใ ๐ข๐ข๐ก๐ก = ๐๐๐ก๐ก2 โ โ๐ก๐ก = ๐ฃ๐ฃ๐ก๐ก2โ๐ก๐ก โ โ๐ก๐ก = (๐ฃ๐ฃ๐ก๐ก2 โ 1)โ๐ก๐ก
ใงใใใใใใงใ๐ฃ๐ฃ๐ก๐กใจโ๐ก๐ก ใฏ็ฌ็ซใชใฎใงใ
๐ธ๐ธ[๐ข๐ข๐ก๐ก] = ๐ธ๐ธ[(๐ฃ๐ฃ๐ก๐ก2 โ 1)โ๐ก๐ก] = ๐ธ๐ธ[๐ฃ๐ฃ๐ก๐ก2 โ 1]๐ธ๐ธ[โ๐ก๐ก] = (1โ 1)๐ธ๐ธ[โ๐ก๐ก] = 0
ใจใชใใใใใง๐ก๐ก > ๐ ๐ ใจใใใจใ
๐๐๐๐๐ฃ๐ฃ(๐ข๐ข๐ก๐ก,๐ข๐ข๐ ๐ ) = ๐ธ๐ธ[๐ข๐ข๐ก๐ก๐ข๐ข๐ ๐ ]
= ๐ธ๐ธ[(๐ฃ๐ฃ๐ก๐ก2 โ 1)โ๐ก๐ก(๐ฃ๐ฃ๐ ๐ 2 โ 1)โ๐ ๐ ]
= ๐ธ๐ธ[(๐ฃ๐ฃ๐ก๐ก2 โ 1)]๐ธ๐ธ[โ๐ก๐ก(๐ฃ๐ฃ๐ ๐ 2 โ 1)โ๐ ๐ ] = 0
ใจใชใใๆฌกใซใ{๐๐๐ก๐ก2}ใ ARMA(2,1) ้็จใจใชใใใจใ็คบใใๆขใซ็คบใใใจใใใ
๐๐๐ก๐ก2 = ๐ผ๐ผ0 + (๐ผ๐ผ1 + ๐ฝ๐ฝ1)๐๐๐ก๐กโ12 + ๐ผ๐ผ2๐๐๐ก๐กโ22 โ ๐ฝ๐ฝ1๐ข๐ข๐ก๐กโ1 + ๐ข๐ข๐ก๐ก
ใจใชใใ๐ข๐ข๐ก๐กใฏใใฏใคใใใคใบ๏ผ๐ธ๐ธ[๐ข๐ข๐ก๐ก] = 0ใ๐๐๐๐๐ฃ๐ฃ(๐ข๐ข๐ก๐ก,๐ข๐ข๐ ๐ ) = 0๏ผใงใใใใใ๐๐๐ก๐ก2ใฏ ARMA(2,1)
้็จใจใชใใใใใง่ชๅทฑๅๅธฐ้จๅใฎไฟๆฐใฏ๐ผ๐ผ1 + ๐ฝ๐ฝ1ใจ๐ผ๐ผ2ใMA ้จๅใฎไฟๆฐใฏโ๐ฝ๐ฝ1ใจใชใใ
(b) GARCH(2, 1)้็จ
โ๐ก๐ก = ๐ผ๐ผ0 + ๐ผ๐ผ1๐๐๐ก๐กโ12 + ๐ฝ๐ฝ1โ๐ก๐กโ1 + ๐ฝ๐ฝ2โ๐ก๐กโ2
ใจใใใใใใงไธก่พบใซไบๆธฌ่ชคๅทฎ๐ข๐ข๐ก๐ก = ๐๐๐ก๐ก2 โ โ๐ก๐กใๅ ใใใจ
๐๐๐ก๐ก2 = ๐ผ๐ผ0 + ๐ผ๐ผ1๐๐๐ก๐กโ12 + ๐ผ๐ผ2๐๐๐ก๐กโ22 + ๐ฝ๐ฝ1โ๐ก๐กโ1 + ๐ฝ๐ฝ2โ๐ก๐กโ2 + ๐ข๐ข๐ก๐ก
ใจใชใใใใใง๐ข๐ข๐ก๐กโ1 = ๐๐๐ก๐กโ12 โ โ๐ก๐กโ1ใใใโ๐ก๐กโ1 = ๐๐๐ก๐กโ12 โ ๐ข๐ข๐ก๐กโ1ใจใชใใๅๆงใซใโ๐ก๐กโ2 = ๐๐๐ก๐กโ22 โ ๐ข๐ข๐ก๐กโ2ใจใชใใใใใใไธๅผใซไปฃๅ ฅใใใจใ
๐๐๐ก๐ก2 = ๐ผ๐ผ0 + ๐ผ๐ผ1๐๐๐ก๐กโ12 + ๐ผ๐ผ2๐๐๐ก๐กโ22 + ๐ฝ๐ฝ1(๐๐๐ก๐กโ12 โ ๐ข๐ข๐ก๐กโ1) + ๐ฝ๐ฝ2(๐๐๐ก๐กโ22 โ ๐ข๐ข๐ก๐กโ2) + ๐ข๐ข๐ก๐ก
= ๐ผ๐ผ0 + (๐ผ๐ผ1 + ๐ฝ๐ฝ1)๐๐๐ก๐กโ12 + (๐ผ๐ผ2 + ๐ฝ๐ฝ2)๐๐๐ก๐กโ22 + ๐ข๐ข๐ก๐ก โ ๐ฝ๐ฝ1๐ข๐ข๐ก๐กโ1 โ ๐ฝ๐ฝ2๐ข๐ข๐ก๐กโ2
ใจใชใใใใใฏใพใใซ ARMA(2,2)้็จใงใใใ
(c) GARCH(p, q)้็จ
โ๐ก๐ก = ๐ผ๐ผ0 + ๐ผ๐ผ1๐๐๐ก๐กโ12 + โฏ+ ๐ผ๐ผ๐๐๐๐๐ก๐กโ๐๐2 + ๐ฝ๐ฝ1โ๐ก๐กโ1 + โฏ+ ๐ฝ๐ฝ๐๐โ๐ก๐กโ๐๐
ใจใใใใใฎใจใใ๐ข๐ข๐ก๐ก = ๐๐๐ก๐ก2 โ โ๐ก๐กใฏโ๐ก๐ก = ๐๐๐ก๐ก2 โ ๐ข๐ข๐ก๐กใงใใใใใใๅทฆ่พบใซไปฃๅ ฅใใฆๆด็ใใใจ
๐๐๐ก๐ก2 = ๐ผ๐ผ0 + ๏ฟฝ๐ผ๐ผ๐๐๐๐๐ก๐กโ๐๐2
๐๐
๐๐=1
+๏ฟฝ๐ฝ๐ฝ๐๐โ๐ก๐กโ๐๐
๐๐
๐๐=1
+ ๐ข๐ข๐ก๐ก
![Page 4: [1] 2 AR(1) (3.5)tyabu/enders/solutions_ch3.pdfย ยท 2019-11-05ย ยท ๐ธ๐ธ[๐๐. ๐ก๐ก2] = ๐ผ๐ผ. 0. 1 โโ ๐ผ๐ผ. ๐๐ ๐๐ ๐๐=1. ใๅพใใไปฅไธใใใๆกไปถใชใๅนณๅใๅๆฃใ่ชๅทฑๅ
ฑๅๆฃใฏๆ็นใซไพๅญใใฆใใชใใใใ](https://reader035.fdocuments.net/reader035/viewer/2022062915/5e97b8f0deafcd264728dc62/html5/thumbnails/4.jpg)
ใใจใชใใไธๅผใซโ๐ก๐กโ๐๐ = ๐๐๐ก๐กโ๐๐2 โ ๐ข๐ข๐ก๐กโ๐๐ใไปฃๅ ฅใใใจ
๐๐๐ก๐ก2 = ๐ผ๐ผ0 + โ (๐ผ๐ผ๐๐ + ๐ฝ๐ฝ๐๐)๐๐๐ก๐กโ๐๐2๐๐๐๐=1 + ๐ข๐ข๐ก๐ก โ โ ๐ฝ๐ฝ๐๐๐ข๐ข๐ก๐กโ๐๐
๐๐๐๐=1
ใจใชใใใใใใฃใฆใ๐๐๐ก๐ก2ใฏ ARMA(m, p)ใจใชใใใใใงใ๐๐๐ก๐กโ๐๐2 ใฎไฟๆฐใฏ๐ผ๐ผ๐๐ + ๐ฝ๐ฝ๐๐ใจใชใใ
[5] a)b) ๅทฆไธใฎ่กจใงใฏใๅใขใใซใใใใผใฟใ็บ็ใใใ็ตๆใใพใจใใฆใใใๅณไธๅณใงใฏใ
ใใใใฎๅใใ็คบใใฆใใใ
ใขใใซ 1 ใฏๅใชใ AR(1)ใขใใซใงใใใ2 ๆใจ 3 ๆใฎ่ฒ ใฎใทใงใใฏใฎๅฝฑ้ฟใๅใใฆใy1 ใฎ
ๅคใฏไฝไธใใฆใใใใใใฎๅฝฑ้ฟใฏใใใซๆถใใใใขใใซ 2 ใฏใใฏใคใใใคใบ+ARCH-M ๅนๆ
ใงใใใ่ฒ ใฎใทใงใใฏใฎๅฝฑ้ฟใๅใใฆใARCH-M ๅนๆใฎใใใy2 ใฎๆฐดๆบใๅคงใใไฝไธใใฆ
ใใใใขใใซ 3 ใฏใAR(1)ใซ ARCH-M ๅนๆใใใใขใใซใงใใใ่ฒ ใฎใทใงใใฏใฎๅฝฑ้ฟใๅ
ใใฆใARCH-M ๅนๆใซใใ y3 ใฎๆฐดๆบใไฝไธใใAR(1)ๅนๆใฎใใๅฝฑ้ฟใใใใซๆกๅคงใใฆใ
ใใๅนณๅใๆฏ่ผใใใจใy3 ใๆใๅฐใใใชใฃใฆใใใใพใใๅๆฃใ y3 ใๆใๅคงใใใ
[6] ๆกไปถไปใๆๅพ ๅคใฏ
๐ธ๐ธ๐ก๐กโ1๐ฆ๐ฆ๐ก๐ก = ๐ธ๐ธ๐ก๐กโ1(๐๐0 + ๐๐1๐ฆ๐ฆ๐ก๐กโ1 + ๐๐๐ก๐ก) = ๐๐0 + ๐๐1๐ฆ๐ฆ๐ก๐กโ1
ใจใชใใใพใใๆกไปถไปใๅๆฃใฏ
๐ธ๐ธ๐ก๐กโ1[(๐ฆ๐ฆ๐ก๐ก โ ๐ธ๐ธ๐ก๐กโ1๐ฆ๐ฆ๐ก๐ก)2] = ๐ธ๐ธ๐ก๐กโ1๐๐๐ก๐ก2
ใจใชใใ
ๆฌกใซใๆกไปถใชใๅๆฃใๆฑใใใใใใง๐ฆ๐ฆ๐ก๐กใฎ็นๆฎ่งฃใฏใ
๐ฆ๐ฆ๐ก๐ก =๐๐0
1 โ ๐๐1+ ๐๐๐ก๐ก + ๐๐1๐๐๐ก๐กโ1 + ๐๐12๐๐๐ก๐กโ2 + โฏ
ใงใใใใใ๐ธ๐ธ[๐ฆ๐ฆ๐ก๐ก] = ๐๐0/(1โ ๐๐1)ใจใชใใใพใ
๐ฃ๐ฃ๐๐๐ฃ๐ฃ(๐ฆ๐ฆ๐ก๐ก) = ๐ธ๐ธ[(๐๐๐ก๐ก + ๐๐1๐๐๐ก๐กโ1 + ๐๐12๐๐๐ก๐กโ2 +โฏ )2] =๐ธ๐ธ[๐๐๐ก๐ก2]1 โ ๐๐12
ใจใชใใใใใง
๐๐๐ก๐ก = ๐ฃ๐ฃ๐ก๐ก๏ฟฝ๐ผ๐ผ0 + ๐ผ๐ผ1๐๐๐ก๐กโ12 + ๐ผ๐ผ2๐๐๐ก๐กโ22
ๆ็น y1 y2 y3 epsiron0 0 0 0 01 1 1 1 12 -0.5 -2 -1.5 -13 -2.25 -3 -3.75 -24 -0.125 -3 -4.875 15 0.9375 0 -2.4375 1
ๅนณๅ -0.1875 -1.4 -2.3125 0ๅๆฃ 1.757813 3.3 5.070313 2
-6
-5
-4
-3
-2
-1
0
1
2
0 1 2 3 4 5
y1
y2
y3
![Page 5: [1] 2 AR(1) (3.5)tyabu/enders/solutions_ch3.pdfย ยท 2019-11-05ย ยท ๐ธ๐ธ[๐๐. ๐ก๐ก2] = ๐ผ๐ผ. 0. 1 โโ ๐ผ๐ผ. ๐๐ ๐๐ ๐๐=1. ใๅพใใไปฅไธใใใๆกไปถใชใๅนณๅใๅๆฃใ่ชๅทฑๅ
ฑๅๆฃใฏๆ็นใซไพๅญใใฆใใชใใใใ](https://reader035.fdocuments.net/reader035/viewer/2022062915/5e97b8f0deafcd264728dc62/html5/thumbnails/5.jpg)
ใงใใใใพใ๐ธ๐ธ[๐๐๐ก๐ก] = 0ใ๐ธ๐ธ[๐ฃ๐ฃ๐ก๐ก] = 0ใใ ๐ธ๐ธ[๐๐๐ก๐ก2] = ๐ธ๐ธ[๐ฃ๐ฃ๐ก๐ก2]๐ธ๐ธ[๐ผ๐ผ0 + ๐ผ๐ผ1๐๐๐ก๐กโ12 + ๐ผ๐ผ2๐๐๐ก๐กโ22 ]
= ๐ผ๐ผ0 + ๐ผ๐ผ1๐ธ๐ธ[๐๐๐ก๐กโ12 ] + ๐ผ๐ผ2๐ธ๐ธ[๐๐๐ก๐กโ22 ]
ใจใชใใๆกไปถใชใๅๆฃใใๆ้ใ้ใใฆไธๅฎใงใใใชใ(๐ธ๐ธ[๐๐๐ก๐ก2] = ๐ธ๐ธ[๐๐๐ก๐กโ12 ] = ๐ธ๐ธ[๐๐๐ก๐กโ22 ])
๐ธ๐ธ[๐๐๐ก๐ก2] =๐ผ๐ผ0
1 โ ๐ผ๐ผ1 โ ๐ผ๐ผ2
ใจใชใใใใใใฃใฆใ๐ฆ๐ฆ๐ก๐กใฎๆกไปถใชใๅๆฃใฏใ
๐ฃ๐ฃ๐๐๐ฃ๐ฃ(๐ฆ๐ฆ๐ก๐ก) =๐ธ๐ธ[๐๐๐ก๐ก2]1 โ ๐๐12
=1
1 โ ๐๐12๐ผ๐ผ0
1 โ ๐ผ๐ผ1 โ ๐ผ๐ผ2
[7] ๅบๆฌ็ตฑ่จ้ใ็ขบ่ชใใใใWorkfile Window ใใ y ใ้ธๆใใViewโDescriptive
Statistics&TablesโStats Table ใจใใใจใไปฅไธใฎ็ป้ขใ่กจ็คบใใใใ
ๆจๆฌๅนณๅใฏ 0.263ใๆจๆฌๆจๆบๅๅทฎใฏ 4.894ใๆๅคงๅคใๆๅฐๅคใฏโ10.8ใ15.15 ใจใชใใ
(a) AR(1)ใขใใซใๆจๅฎใใใใใls y y(-1)ใจ command window ใซๅ ฅๅใใใจไปฅไธใฎๆจๅฎ็ตๆ
ใๅบๅใใใใ
(b) Equation WindowใซใใใฆViewโResidual DiagnosticsโCorrelogram Q-statisticsใจ้ธๆ
![Page 6: [1] 2 AR(1) (3.5)tyabu/enders/solutions_ch3.pdfย ยท 2019-11-05ย ยท ๐ธ๐ธ[๐๐. ๐ก๐ก2] = ๐ผ๐ผ. 0. 1 โโ ๐ผ๐ผ. ๐๐ ๐๐ ๐๐=1. ใๅพใใไปฅไธใใใๆกไปถใชใๅนณๅใๅๆฃใ่ชๅทฑๅ
ฑๅๆฃใฏๆ็นใซไพๅญใใฆใใชใใใใ](https://reader035.fdocuments.net/reader035/viewer/2022062915/5e97b8f0deafcd264728dc62/html5/thumbnails/6.jpg)
ใใใจไปฅไธใฎ็ป้ขใๅบๅใใใใใใใใฟใใจใๆฎๅทฎใฎ ACF ใจ PACF ใฏใจใใซๅฐใใช
ๅคใใจใฃใฆใใใใพใใQ-Stat ใใฟใใจใใฉใใๅฐใใชๅคใงใใใp ๅคใฏ 10%ใ่ถ ใใฆ
ใใใใใ็ณปๅ็ธ้ขใฏๅญๅจใใชใใใใฎ็ตๆใใใๆฎๅทฎใฏใใฏใคใใใคใบใงใใใAR(1)
ใฏ่ฏใใขใใซใงใใใจใใใใใ
(c)ๆฎๅทฎใฎ 2 ไนใฎ ACF ใจ PACF ใใฟใฆใฟใใใEquation Window ใซใใใฆ ViewโResidual
DiagnosticsโCorrelogram Squared Residuals ใ้ธๆใใใจไปฅไธใฎ็ป้ขใๅบๅใใใใใใ
ใใฟใใจใACF ใจ PACF ใฏ้ซใๅคใใจใฃใฆใใใๆฎๅทฎใฎ 2 ไนใซใฏ็ณปๅ็ธ้ขใใใใใจใ
็ขบ่ชใงใใใใใใใฃใฆใARCH ๅนๆใฏใใใจใใใใ
![Page 7: [1] 2 AR(1) (3.5)tyabu/enders/solutions_ch3.pdfย ยท 2019-11-05ย ยท ๐ธ๐ธ[๐๐. ๐ก๐ก2] = ๐ผ๐ผ. 0. 1 โโ ๐ผ๐ผ. ๐๐ ๐๐ ๐๐=1. ใๅพใใไปฅไธใใใๆกไปถใชใๅนณๅใๅๆฃใ่ชๅทฑๅ
ฑๅๆฃใฏๆ็นใซไพๅญใใฆใใชใใใใ](https://reader035.fdocuments.net/reader035/viewer/2022062915/5e97b8f0deafcd264728dc62/html5/thumbnails/7.jpg)
(d)ๆฎๅทฎ 2 ไนใๆฎๅทฎ 2 ไนใฎใฉใฐใงๅๅธฐใใฆใฟใใใEquation Window ใซใใใฆ Viewโ
Residual DiagnosticsโHeteroskedasticity Test ใจใใHeteroskedasticity Window ใซใใใฆ
ARCH ใ้ธใณใNumber of Lags ใฏ 1 ใจใใใใใใฆใOK ใจใใใจใไปฅไธใฎ็ป้ขใๅบๅ
ใใใใใใใใฟใใจใๆฎๅทฎ 2 ไนใฎใฉใฐใฏไฟๆฐใ 0.47 ใงใใใใใฎ t ๅคใฏ 5.27 ใจ้ซใใ
ใพใใTR2ใฏ 22.02777 ใจๅคงใใใๅฏพๅฟใใ p ๅคใฏ 0.000 ใจใชใฃใฆใใใไปฅไธใใใๆฎๅทฎ
2 ไนใซใฏ็ณปๅ็ธ้ขใๆฎใฃใฆใใใARCH ๅนๆใใใใใจใๅใใใ
(e)ๅนณๅใฎๅผใฏ AR(1)ใจใใฆใ่ชคๅทฎ้ ใฏ ARCH(1)ใจใใฆๆจๅฎใใใใใEquation Estimation
ใฆใฃใณใใฆใซใใใฆใๆจๅฎๆณ Method ใจใใฆ ARCH-Autoregressive Conditional
Heteroskedasticity ใ้ธๆใใใจๅทฆไธใฎๅณใฎใใใช็ป้ขใซๅใๆฟใใใๅณใฎ้ใใซๅ ฅๅใ
ใใจๆจ่จ็ตๆใๅพใใใ๏ผๅณไธใฎๅณ๏ผใ
![Page 8: [1] 2 AR(1) (3.5)tyabu/enders/solutions_ch3.pdfย ยท 2019-11-05ย ยท ๐ธ๐ธ[๐๐. ๐ก๐ก2] = ๐ผ๐ผ. 0. 1 โโ ๐ผ๐ผ. ๐๐ ๐๐ ๐๐=1. ใๅพใใไปฅไธใใใๆกไปถใชใๅนณๅใๅๆฃใ่ชๅทฑๅ
ฑๅๆฃใฏๆ็นใซไพๅญใใฆใใชใใใใ](https://reader035.fdocuments.net/reader035/viewer/2022062915/5e97b8f0deafcd264728dc62/html5/thumbnails/8.jpg)
ใใฃใฆใๆจๅฎ็ตๆใฏไปฅไธใจใชใใๆ็งๆธใจใปใผๅใ็ตๆใๅพใใใฆใใใ
yt = 0.886yt-1 + ฮตt ht = 1.17 + 0.663ฮตt-12
(33.00) (4.37) (3.01)
[8](a)ARCH-M ้็จใๆจๅฎใใใใใEquation Window ใๅทฆไธใฎใใใซ้ธๆใใใARCH ้
็จใจใฎ้ใใฏ้ ็ฎ ARCH-M ใซใใใฆ Variance ใ้ธๆใใใใจใงใใใใใใใใใจใง
ๅนณๅใฎๅผใซๆกไปถไปใๅๆฃใ่ชฌๆๅคๆฐใจใใฆๅ ใใใใจใใงใใใใใใฆ OK ใจใใใจใ
ๅณไธใฎ็ป้ขใๅพใใใใ
ๆจๅฎ็ตๆใใพใจใใใจไปฅไธใจใชใใ
yt = 0.917 + 0.625ht + ฮตt ht = 0.108 + 0.580ฮตt-12
(13.99) (1.79) (5.73) (2.55)
(b)ใใฎใใใ็พๅจใฎใขใใซใฏไธ้ฉๅฝใจใใใใๆฎๅทฎใจๆฎๅทฎ 2 ไนใฎ ACFใPACF ใ่ชฟในใฆใฟ
ใใจใ็ณปๅ็ธ้ขใๆฎใฃใฆใใใใจใๅใใใใใใฏ ViewโResidual Diangnosticsโ
Correlogram Q-statistics ใใใใฏ Correlogram Squared Residuals ใจใใฆ็ขบ่ชใงใใใๅฅใฎ
ใขใใซใจใใฆใGARCH(1,1)ใ่ฉฆใใฆใฟใใใใใใใใจใๆฎๅทฎใซใฏใใพใ ็ณปๅ็ธ้ขใ
ๆฎใใใๆฎๅทฎ 2 ไนใฏ็ณปๅ็ธ้ขใๆถใใใใจใ็ขบ่ชใงใใใGARCH ใฎๆฌกๆฐใใใใใใจ
ใงใ็ณปๅ็ธ้ขใใฉใใชใใใ็ขบ่ชใใฆใใใใใใ
[9] (a)RGDP.XLS ใ้ใใEviews ใซใใผใฟใๅ ฅๅใใใใGDP ใฎๆ้ท็ใ y ใจๅฎ็พฉใใใ genr y=log(rgdp/rgdp(-1))
ใใใฆใๅฎๆฐ้ ใๅซใใ AR(1)ใงๆจๅฎใใใใใls y c y(-1)ใจๅ ฅๅใใใจๅทฆไธใฎ็ป้ขใฎ็ตๆ
ใๅพใใใๆ็งๆธใจใปใผๅใ็ตๆใๅพใใใใๆฌกใซใใฉใฐใ 4 ใค๏ผ1 ๅนดๅ๏ผใพใง็จใใฆใ
ๆฎๅทฎ 2 ไนใฎ LM ๆคๅฎใ่กใใๆฎๅทฎ 2 ไนใๆฎๅทฎใฎ 2 ไนใฎใฉใฐใงๅๅธฐใใใจๅณไธใฎ็ป้ขใๅพ
![Page 9: [1] 2 AR(1) (3.5)tyabu/enders/solutions_ch3.pdfย ยท 2019-11-05ย ยท ๐ธ๐ธ[๐๐. ๐ก๐ก2] = ๐ผ๐ผ. 0. 1 โโ ๐ผ๐ผ. ๐๐ ๐๐ ๐๐=1. ใๅพใใไปฅไธใใใๆกไปถใชใๅนณๅใๅๆฃใ่ชๅทฑๅ
ฑๅๆฃใฏๆ็นใซไพๅญใใฆใใชใใใใ](https://reader035.fdocuments.net/reader035/viewer/2022062915/5e97b8f0deafcd264728dc62/html5/thumbnails/9.jpg)
ใใใใใใงใๆ็งๆธใจใปใผๅใ็ตๆใๅ็พใงใใใ
1984 ๅนดไปฅ้ใฎใใฉใใฃใชใใฃไฝไธใ็ขบใใใใใใใใใผๅคๆฐ d1 ใๅฐๅ ฅใใฆใฟใ
๏ผ1984Q1 ไปฅ้ใฏ d1 =1ใใใไปฅๅใฏ d1 =0 ใจใใ๏ผใ
genr d1=@date>@dateval("1983Q4")
ๅๆฃๅผใซใARCH(1)ๅนๆใจ d1 ใๅซใใฆๅๅธฐใใใEquation Window ใฆใฃใณใใฆใฎ Variance
regressors ใซ d1 ใจๅ ฅๅใใใจๅๆฃๅผใซใใใผๅคๆฐใ่ชฌๆๅคๆฐใจใใฆ่ฟฝๅ ใงใใใๅทฆไธ็ป้ขใ
ๆจๅฎใฎใใใฎๅ ฅๅใงใใใๅณไธ็ป้ขใๆจๅฎ็ตๆใจใชใใd1 ใฎไฟๆฐใฏใใคใในใงๆๆใงใใ
ใใจใใใ1984Q4 ไปฅ้ใซใใฉใใฃใชใใฃใๆๅธธ็ใซๅคงใใๆธๅฐใใใใจใๅใใใๅ ทไฝ็
ใซใฏใ1984Q4 ไปฅๅใฏใๅๆฃๅผใฎๅฎๆฐ้ ใ 0.000110 ใงใใฃใใฎใใ1984Q4 ไปฅ้ใฏ
0.0000225(=0.000110-0.000085)ใซๅคงใใไฝไธใใฆใใใ
(b)้่ๅฑๆฉใ่กจใใใใผๅคๆฐใ d2 ใจใใใใใใฏ 2007Q3 ใพใง 0ใใใไปฅ้ใฏ 1 ใจใชใใ
ใใผๅคๆฐใงใใใ
genr d2=@date>@dateval("2007Q3")
![Page 10: [1] 2 AR(1) (3.5)tyabu/enders/solutions_ch3.pdfย ยท 2019-11-05ย ยท ๐ธ๐ธ[๐๐. ๐ก๐ก2] = ๐ผ๐ผ. 0. 1 โโ ๐ผ๐ผ. ๐๐ ๐๐ ๐๐=1. ใๅพใใไปฅไธใใใๆกไปถใชใๅนณๅใๅๆฃใ่ชๅทฑๅ
ฑๅๆฃใฏๆ็นใซไพๅญใใฆใใชใใใใ](https://reader035.fdocuments.net/reader035/viewer/2022062915/5e97b8f0deafcd264728dc62/html5/thumbnails/10.jpg)
ไธ็ป้ขใฏd2ใๆฐใใซๅๆฃๅผใซๅ ใใๅ ดๅใฎๆจๅฎ็ตๆใงใใใใใใใฟใใจใd2ใฎไฟๆฐใฏใ
ใฉในใงใใใๆๆใจใชใฃใฆใใชใใ้่ๅฑๆฉใใใฉใใฃใชใใฃใๅขๅ ใใใๅนๆใฏไธๆ็
ใงใใใใจใๅใใใใใใซๅฏพใใฆใd1ใฎไฟๆฐใฏใใคใในใงๆๆใงใใใใจใใใ1984Q4ไปฅ้ใซใใฉใใฃใชใใฃใๆๅธธ็ใซๆธๅฐใใใใจใๅใใใ
(c)ๅฎ่ณชๆถ่ฒปrconsใจๅฎ่ณชๆ่ณroinvใฎๅคๅ็ใใใใใใy2ใy3ใจๅฎ็พฉใใใ
genr y2=log(rcons/rcons(-1))
genr y3=log(rinv/rinv(-1))
ใใใใฎๅๆฃๅผใซ d1 ใๅ ใใฆๆจๅฎใใ็ตๆใฏไปฅไธใจใชใ๏ผๅทฆไธใ y2ใๅณไธใ y3๏ผใ
ใใใใใฟใใจใd1 ใฎไฟๆฐใฏๆๆใซ่ฒ ใงใใใ1984Q4 ไปฅ้ใซใใฉใใฃใชใใฃใๆๅธธ็
ใซๆธๅฐใใใใจใๅใใใใใจใใฐใๅฎ่ณชๆถ่ฒปใใฟใใจใๅๆฃๅผใฎๅฎๆฐ้ ใฏ 0.0000672 ใ
ใ 0.0000189(=0.0000672-0.0000483)ใซๅคงใใไฝไธใใฆใใใ [10] EViews ใฎ 3 ็ซ ใฎ่งฃ่ชฌใงใฏใNYSE.XLS ใ็จใใฆๆจๅฎใ่กใฃใฆใใใใใกใใ็ขบ่ชใใฆ
ใใใใใใ