Testing the Difference Between Reliability Coefficients Alpha and Omega.
Reliable measurements are key to social science research. Multiple measures of reliability of the total score have been developed, including coefficient alpha, coefficient omega, the greatest lower bound reliability, and others. Among these, the coefficient alpha has been most widely used, and it is...
| Publicado en: | Educational & Psychological Measurement Vol. 77; no. 2; pp. 185 - 204 |
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| Autores principales: | , |
| Formato: | Artículo |
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Sage Publications Inc.
Apr2017
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| Acceso en línea: | Ver este registro en EBSCOhost |
| fields | @attributes: recordID: 1 pdfLink: plink: https://search.ebscohost.com/login.aspx?direct=true&db=ssf&AN=121966615&site=ehost-live header: @attributes: shortDbName: ssf uiTerm: 121966615 longDbName: Social Sciences Full Text (H.W. Wilson) uiTag: AN controlInfo: bkinfo: jinfo: jid: 00131644 EPM jtl: Educational & Psychological Measurement issn: 00131644 maglogo: Y pubinfo: dt: Apr2017 vid: 77 iid: 2 pid: 344 pub: Sage Publications Inc. artinfo: ui: 121966615 10.1177/0013164416658325 ppf: 185 ppct: 19 formats: tig: atl: Testing the Difference Between Reliability Coefficients Alpha and Omega. aug: au: Deng, Lifang Chan, Wai affil: Beihang University, Beijing, China The Chinese University of Hong Kong, Hong Kong, China su: Reliability (Personality trait) Social sciences Computer software Confidence intervals Statistical correlation Research funding Behavioral research Sampling errors sug: subj: Reliability (Personality trait) Social sciences Software publishers (except video game publishers) Computer and software stores Computer and Computer Peripheral Equipment and Software Merchant Wholesalers Computer, computer peripheral and pre-packaged software merchant wholesalers Research and Development in the Social Sciences and Humanities Computer software Confidence intervals Statistical correlation Research funding Behavioral research Sampling errors keyword: coefficient alpha coefficient omega confidence intervals standard errors coefficient alpha coefficient omega confidence intervals standard errors ab: Reliable measurements are key to social science research. Multiple measures of reliability of the total score have been developed, including coefficient alpha, coefficient omega, the greatest lower bound reliability, and others. Among these, the coefficient alpha has been most widely used, and it is reported in nearly every study involving the measure of a construct through multiple items in social and behavioral research. However, it is known that coefficient alpha underestimates the true reliability unless the items are tau-equivalent, and coefficient omega is deemed as a practical alternative to coefficient alpha in estimating measurement reliability of the total score. However, many researchers noticed that the difference between alpha and omega is minor in applications. Since the observed differences in alpha and omega can be due to sampling errors, the purpose of the present study, therefore, is to propose a method to evaluate the difference of coefficient alpha (<named-content> α ^ </named-content>) and omega (<named-content> ω ^ </named-content>) statistically. In particular, the current article develops a procedure to estimate the SE of (<named-content> ω ^ − α ^ </named-content>) and consequently the confidence interval (CI) for (<named-content> ω − α </named-content>). This procedure allows us to test whether the observed difference (<named-content> ω ^ − α ^ </named-content>) is due to sample error or <named-content> ω ^ </named-content> is significantly greater than <named-content> α ^ </named-content>. The developed procedure is then applied to multiple real data sets from well-known scales to empirically verify the values of (<named-content> ω ^ − α ^ </named-content>) in practice. Results showed that in most of the comparisons the differences are significantly above zero but cases also exist where the CIs contain zero. An R program for calculating <named-content> ω ^ </named-content>, <named-content> α ^ </named-content>, and the SE of (<named-content> ω ^ − α ^ </named-content>) is also included in the present study so that the developed procedure is easily accessible to applied researchers. pubtype: Academic Journal doctype: Article src: R language: English refInfo: copyright: @attributes: flag: N holdings: @attributes: islocal: N |
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