A Note on Using and Unbiased Weight Matrix in the ADF Test Statistic
- 1 October 1995
- journal article
- Published by Taylor & Francis in Multivariate Behavioral Research
- Vol. 30 (4) , 453-459
- https://doi.org/10.1207/s15327906mbr3004_1
Abstract
In covariance structure analysis, the asymptotically distribution-free (ADF) method fails to work satisfactorily unless the sample is extremely large. Simulation studies report that the ADF test statistics observed arc usually too large and correct models arc then over-rejected. It is known that the accuracy of the ADF test statistic depends on the estimation of the weight matrix. In existing literature and computer software, a biased estimator W is used as an estimate of the unknown weight matrix. In this article. we suggest that W, an unbiased estimate of the weight matrix, may eliminate the small or intermediate sample size bias of the ADF test statistic. Results show that the test statistics based on W and W arc highly similar. The poor performance of the ADF method was not caused by the use of a biased weight matrix in the model studied in this article.Keywords
This publication has 2 references indexed in Scilit:
- Bootstrap‐corrected ADF test statistics in covariance structure analysisBritish Journal of Mathematical and Statistical Psychology, 1994
- Scaled test statistics and robust standard errors for non‐normal data in covariance structure analysis: A Monte Carlo studyBritish Journal of Mathematical and Statistical Psychology, 1991