Ensuring positiveness of the scaled difference chi-square test statistic

A scaled difference test statistic T~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~d is asymptotically equivalent to the scaled difference test statistic T¯d...

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Detalles Bibliográficos
Autores: Satorra, Albert, Bentler, Peter M.
Tipo de recurso: artículo
Estado:Versión aceptada para publicación
Fecha de publicación:2010
País:España
Institución:Varias* (Consorci de Biblioteques Universitáries de Catalunya, Centre de Serveis Científics i Acadèmics de Catalunya)
Repositorio:Recercat. Dipósit de la Recerca de Catalunya
OAI Identifier:oai:recercat.cat:10230/46120
Acceso en línea:http://hdl.handle.net/10230/46120
http://dx.doi.org/10.1007/s11336-009-9135-y
Access Level:acceso abierto
Palabra clave:Moment-structures
Goodness-of-fit test
Chi-square difference test statistic
Chi-square distribution
Nonnormality
Descripción
Sumario:A scaled difference test statistic T~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~d is asymptotically equivalent to the scaled difference test statistic T¯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~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¯d that avoids negative chi-square values.