How to Cronchbach Alpha with STATA

For my personal record only. This is how to perform croncbach alpha with stata


Cronbach's alpha examines reliability by determining the internal consistency of a test or the average correlation of items (variables) within the test. In Stata, the alpha command conducts the reliability test.
For example, suppose you wish to test the internal reliability of ten variables, q1 through q10. You could run the following:
  alpha q1-q10, item
In the above example, the item option displays the effects of removing an item from the scale.

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