Composite Reliability statistics lecture

Quantitative statistics lecture

1. Composite Reliability Presenter: Syeda Beena Zaidi 1

2. Key Takeaways Reliability Measure of Internal Consistency Composite Reliability Factor Analysis in SPSS Computation of Composite Reliability Using Excel 2

3. Reliability Reliability concerns consistency, or the extent to which a measuring procedure yields identical results on repeated trials. Quality research must come from measures that have the ability to consistently (i.e. reliably) and accurately detect changes in research participants’ skills, knowledge, attitudes, or behavior. A reliable measure is reproducible and precise; each time it is used it produces the same results, all else being equal Two basic methods of estimating reliability are commonly used in surveys: The test-retest method Measure reliability of a single question The internal consistency method Measure reliability of two or more questions simultaneously 3

4. Reliability Issues in Test-retest reliability The test-retest method is difficult and expensive to use in a survey setting low reliability coefficient might indicate several conditions other than an unreliable measure lack of correlation indicates fundamental variation, not unreliability Memory of respondents 4

5. Internal Consistency It focuses on measuring several indicators of a phenomenon and evaluating their joint consistency or homogeneity The stronger the effect of the latent variable on the questions, the higher is the internal consistency reliability. 5

6. Internal Consistency Internal consistency reliability analysis is a parametric procedure used to evaluate the consistency of results across items within a single scale (i.e., instrument) or subscale that is composed of multiple items. All items in an internally consistent scale assess the same construct. We measure internal consistency with two approaches Cronbach’s alpha Composites reliability Both values are interpreted using the guidelines offered by Nunnally and Bernstein (1994) who suggest 0.7 as a benchmark for a modest reliability applicable. 6

7. Composite Reliability Composite reliability  sometimes called construct reliability is a measure of internal consistency in scale items Procedures for estimating reliability produce a reliability coefficient, which is a correlation coefficient. It ranges from 0 to + 1 When a reliability coefficient is zero, all variability in obtained test scores is due to measurement error. When a reliability coefficient is 1.0, all variability in scores reflects true score variability. 7

8. Computation of Composite Reliability in Excel Whereby, λ (lambda) is the standardized factor loading for item  i   ε is the respective error variance for item  I The error variance (ε) is estimated based on the value of the standardized loading (λ) as: 8

9. Factor Analysis in SPSS Analyze----Dimension Reduction-----Factor 9

10. Select ‘ varimax ’ from rotation tab Select “suppress small coefficients” from options tab Give 0.5 value in cell 10

11.   Items Factor Loadings Government Support During COVID-19 pandemic, the government encourages payment transaction using e-wallets 0.839 During COVID-19 pandemic, the government ensures e-wallets server facilities 0.95 During COVID-19 pandemic, the government encourages payment innovation via e-wallets 0.91 During COVID-19 pandemic, the government controls e-wallets payment operations 0.85   ^2 1-  ^2 CR 0.839 0.70392 0.296079 0.789 0.95 0.9025 0.0975 0.91 0.8281 0.1719 0.85 0.7225 0.2775 Total 3.15702 0.842979 Computation of Composite Reliability in Excel 11

12. Thank you 12