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| = What is the expected total discrepancy score in a R choice task? = | |
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| = What is the expected total rank in a R choice task? = Suppose we have R choices from 1 to k and each of these is equally likely to be the true rank. The expected total rank equals |
Suppose we have R choices from 1 to k and each of these is equally likely to be the true rank. The expected total rank of the absolute value of discrepancies equals |
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Expected total score assuming random guesses at true rank = 2(1+2+3)+2(1+1+2)= 20 = 1x2 + 2x3 + 3x4 = $$\sum_{k=1}^4 (k=1)k $$. |
What is the expected total discrepancy score in a R choice task?
Suppose we have R choices from 1 to k and each of these is equally likely to be the true rank. The expected total rank of the absolute value of discrepancies equals
$$\sum_{k=1}^R (k=1)k $$
For example
R = 4
k=1 |
k=2 |
k=3 |
k=4 |
True Rank |
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Expected total score assuming random guesses at true rank = 2(1+2+3)+2(1+1+2)= 20 = 1x2 + 2x3 + 3x4 = $$\sum_{k=1}^4 (k=1)k $$.