Z-score
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A Z-score shows how an individual value compares to a given distribution.
Z-score Equation:
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Measuring probability of less than z
Table entries represent the area under the
bell curve left of z (aka use probabilities
directly from the table).
To find the probability for the area greater than
z, look up the Z-score and subtract it from 1
(this is the same process for finding a negative
Z-score).
Measuring probability for a Negative Z-score
To find the probability for a negative
Z-score look up the positive version
on this table and subtract it from 1.
Measuring probability that z is greater than the Mean
To find the probability that z is greater
than the mean, look up the Z-score and
subtract 0.5.
