Date of Award
Fall 2023
Document Type
Dissertation
Degree Name
Doctor of Philosophy (PhD)
Department
Psychology
Program/Concentration
Health Psychology
Committee Director
Miguel A. Padilla
Committee Member
James M. Henson
Committee Member
Lucia M. Tabacu
Abstract
There is a focus within the behavioral/social sciences on non-physical, psychological constructs (i.e., constructs). These constructs are indirectly measured using measurement instruments that consist of questions that capture the manifestations of these constructs. The indirect nature of measuring constructs results in a need of ensuring that measurement instruments are reliable. The most popular statistic used to estimate reliability is coefficient alpha as it is easy to compute and has properties that make it desirable to use. Coefficient alpha’s popularity has resulted in a wide breadth of research into its qualities. Notably, research about coefficient alpha’s distribution has led to developments about its confidence intervals (CIs) and implementation through Bayesian methods with corresponding credible intervals (CrIs).
Here, a new method to implement a Bayesian coefficient alpha is proposed. This new method is built on coefficient alpha having a posterior normal distribution based on a posterior mean and variance. To assess the effectiveness of this new method, a simulation was conducted that compared it to previously established methods used to obtain coefficient alpha CI/CrIs. These include bootstrap CIs and Bayesian CrIs that are based on indirectly generating a coefficient alpha posterior though the posterior of the item covariance matrix. All CI/CrIs were assessed for 95% coverage probability. Ultimately, the new method to implement Bayesian coefficient alpha was found to be effective as it tended to have CrIs that were closer and tighter around the target of .95.
Rights
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DOI
10.25777/tz2n-bs24
ISBN
9798381449204
Recommended Citation
DelosReyes, John M..
"A New Method to Determine the Posterior Distribution of Coefficient Alpha"
(2023). Doctor of Philosophy (PhD), Dissertation, Psychology, Old Dominion University, DOI: 10.25777/tz2n-bs24
https://digitalcommons.odu.edu/psychology_etds/421
ORCID
0000-0002-7230-6506