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ERIC Number: EJ887370
Record Type: Journal
Publication Date: 2010-Jun
Pages: 6
Abstractor: As Provided
ISSN: ISSN-0033-3123
Ensuring Positiveness of the Scaled Difference Chi-Square Test Statistic
Satorra, Albert; Bentler, Peter M.
Psychometrika, v75 n2 p243-248 Jun 2010
A scaled difference test statistic T[tilde][subscript d] that can be computed from standard software of structural equation models (SEM) by hand calculations was proposed in Satorra and Bentler (Psychometrika 66:507-514, 2001). The statistic T[tilde][subscript d] is asymptotically equivalent to the scaled difference test statistic T[bar][subscript d] introduced in Satorra (Innovations in Multivariate Statistical Analysis: A Festschrift for Heinz Neudecker, pp. 233-247, 2000), which requires more involved computations beyond standard output of SEM software. The test statistic T[tilde][subscript d] has been widely used in practice, but in some applications it is negative due to negativity of its associated scaling correction. Using the implicit function theorem, this note develops an improved scaling correction leading to a new scaled difference statistic T[bar][subscript d] that avoids negative chi-square values. (Contains 2 footnotes.)
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Publication Type: Journal Articles; Reports - Research
Education Level: N/A
Audience: N/A
Language: English
Sponsor: N/A
Authoring Institution: N/A