Wikipedia about Cronbach's alpha
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Christian
Published: 11062015 11:55 am

I will try to implement this automatically on the test.
"In statistics (Classical Test Theory), Cronbach's \alpha (alpha)[1] is used as a (lowerbound) estimate of the reliability of a psychometric test.
It has been proposed that \alpha can be viewed as the expected correlation of two tests that measure the same construct. By using this definition, it is implicitly assumed that the average correlation of a set of items is an accurate estimate of the average correlation of all items that pertain to a certain construct.[2]
Cronbach's \alpha is a function of the number of items in a test, the average covariance between itempairs, and the variance of the total score."
https://en.wikipedia.org/wiki/Cronbach's_alpha

