When you compute Cronbach’s alpha, you are actually correlating the score for each item with the total score for each individual and then comparing that with the variability present for all individual item scores. The logic is that any individual test taker with a high total test score should have a high(er) score on each item (such as 5, 5, 3, 5, 3, 4, 4, 2, 4, 5 for a total score of 40) and that any individual test taker with a low(er) total test score should have a low(er) score on each individual item (such as 4, 1, 2, 1, 3, 2, 4, 1, 2, 1).
