1. Quick and Easy Alpha Reliability
Suppose you are interested in finding out and reporting the “alpha reliability” of one of the measures you are using in the study
Alpha reliability has to do with the inter-correlation among the items on a (unidimensional) scale.
We want alpha to be .8 or better on a scale of 0-1
Let’s say that you are interested in finding out how reliable your measuring instrument “Modified Social Support Network” (modmos) scale is
Here’s what your data is going to look like:

2. Data File for Reliability Analysis
Data for seven subjects on the six items constituting the Modifed Scale of Social Support; two subjects did not complete the questionnaire

3. Doing Reliability Analysis in SPSS
Open the modmos.sav data file
In Data Editor, Go to Analyze/Scale/ Reliability Analysis
Move all six of the modmos variables into the Items box
Under Model select Alpha
Under Statistics select Item, Scale, and Scale if Item Deleted. Next to Anova, check None (see illustration next slide

4. SPSS Output for Alpha Reliability
Alpha that you will report in your Results section is That’s very good. Note that you could make it higher if you deleted item MODMOS1