如何计算Cronbach's Alpha

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Cronbach's alpha (α) measures internal consistency reliability — whether items measuring the same construct produce correlated scores. α > 0.7 is generally acceptable; > 0.9 is excellent.

分步指南

1. 1α = (k × r̄) / (1 + (k−1) × r̄)
2. 2k = number of items · r̄ = average inter-item correlation
3. 3Higher α: items are more redundant/internally consistent

例题解析