- Input
- Rows: 4,5,4; 3,4,3; 5,5,4; 2,3,2.
- Method
- Treat rows as respondents and columns as items, then compare item variances with total-score variance.
- Formula
- alpha = k/(k - 1) * (1 - sum(item variances) / total-score variance)
- Intermediate steps
- k = 3 items
- Each respondent total is the row sum
- Item variances are computed by column
- Final result
- The calculator reports raw alpha and item diagnostics.
- Interpretation
- Alpha estimates internal consistency for the selected item set.
- Limitation
- Alpha does not prove validity or unidimensionality.