I'm working on data analysis for my dissertation, and I'm banging my head against the wall when it comes to Cronbach's alpha.
I just completed a pretest; after data cleaning, I have 119 valid and complete responses. These 119 participants answered the same six-item Likert-type scale for nine different scenarios.
However, I am not sure at all how to calculate Cronbach's alpha in this case. Do I calculate alpha for each of the nine scenarios then average them together? Or should I have SPSS calculate new variables, with each of the nine instances of the six items compiled together, and then calculating Cronbach's alpha from that?
...or is there a better calculation altogether?