Difference between revisions of "Cronbach's Alpha Values"
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''contributed by Frank LaBanca, EdD'' | ''contributed by Frank LaBanca, EdD'' | ||
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+ | Cronbach's alpha measures internal consistency, meaning how much the items on a scale actually measure the same dimension. For example, when considering instrumentation for quantitative research, part of assessing a reliable instrument would include reviewing the Cronbach's alpha values for the scales. An example of this is reported below, for the School Attitudes Assessment Survey - Revised (SAAS-R): | ||
+ | As reported by McCoach and Siegle (2003), the scores demonstrated a classical theory internal consistency reliability coefficient of at least .85 on each of the five factors. | ||
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+ | McCoach, D. B., & Siegle, D. (2003). The school attitude assessment survey – revised: A new instrument to identify academically able | ||
+ | students who underachieve. ''Educational and Psychological Measurement, 63''(3), 414-429. DOI: 10.1177/0013164402251057. | ||
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+ | "contributed by Lauren Moyer" |
Revision as of 08:22, 13 December 2019
Internal consistency
Cronbach's Alpha | Internal Consistency |
---|---|
0.9 ≤ α | Excellent |
0.8 ≤ α < 0.9 | Good |
0.7 ≤ α < 0.8 | Adequate |
0.6 ≤ α < 0.7 | Questionable |
contributed by Frank LaBanca, EdD
Cronbach's alpha measures internal consistency, meaning how much the items on a scale actually measure the same dimension. For example, when considering instrumentation for quantitative research, part of assessing a reliable instrument would include reviewing the Cronbach's alpha values for the scales. An example of this is reported below, for the School Attitudes Assessment Survey - Revised (SAAS-R):
As reported by McCoach and Siegle (2003), the scores demonstrated a classical theory internal consistency reliability coefficient of at least .85 on each of the five factors.
McCoach, D. B., & Siegle, D. (2003). The school attitude assessment survey – revised: A new instrument to identify academically able
students who underachieve. Educational and Psychological Measurement, 63(3), 414-429. DOI: 10.1177/0013164402251057.
"contributed by Lauren Moyer"