1. 用图表检验Analyze -> regression -> Linear-> Plots
8 R, v: {* M1 ^' Y6 ?6 |Scatter plot of the standardised residuals on the standardised predicted values (ZRESID as the Y variable, and ZPRED as the X variable* ~- R ]7 o5 y0 I
4 s+ {2 X4 l9 p# Q如果图表显示有可能存在异方差,需要用统计检验来进一步检测异方差是否确实存在。: Q0 i6 o3 S: h$ f* h, B5 |( i
2. 用统计检验+ l1 N) z1 N* `$ g
Heteroscedasticity——Testing and Correcting in SPSS.pdf
Gwilym Pryce March 2002.doc
(172.5 KB, 下载次数: 4)
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Levene’s Test. B6 B* ^8 C4 b' y- o0 Z
Goldfeld-Quandt Test
! `/ n- L9 _+ ]' fBreusch-Pagan Test
8 ?( d& R( m6 C0 `% q, v+ s( cWhite‘s Test (比较常用来检验异方差)
) W% L; m/ }% I+ E7 X0 [Assume you want to run a regression of wage on age, work experience,education, gender, and a dummy for sectorofemployment (whether employed in the public sector). wage = function(age, workexperience, education, gender, sector) or, as your textbook will have it, wage = b1 + b2*age + b3*work experience+ b4*education + b5*gender + b6*sector The White’s test is usually used as a test for heteroskedasticity. In this test, a regression of the squares ofthe residuals is run on the variables suspected of causing theheteroskedasticity, their squares, and cross products. (residuals)2 = b0 + b1 educ + b2 work_ex+ b3 (educ)2 + b4 (work_ex)2 + b5(educ*work_ex) 3 x6 L; @& a7 K' T; J* O% Q' `
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White’s Test · Calculate n*R2 à R2 = 0.037, n=2016 à Thus, n*R2 = .037*2016 = 74.6. ) \0 u3 F+ b! {. D
· Compare this value with c2 (n), i.e.with c2 (2016)
( h3 o- z7 p: ]) s8 U! u(c2 is the symbol for theChi-Square distribution) 1 m. E# `* M9 T, l/ @
c2 (2016) = 124obtained from c2 table. (For 955 confidence) As n*R2 < c2 ,heteroskedasticity can not be confirmed.
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8 A2 z( y* ~. H# c) s请参考:regression_explained_SPSS
regression_explained_SPSS.doc
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