What does a high and a low z-score mean?

1 Answer
Jan 17, 2017

Answer:

A high #z#-score means a very low probability of data above this #z#-score and a low #z#-score means a very low probability of data below this #z#-score..

Explanation:

A high #z#-score means a very low probability of data above this #z#-score. For example, the figure below shows the probability of #z#-score above #2.6#.

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Probability for this is #0.47%#, which is less than half-percent. Note that if #z#-score rises further, area under the curve fall and probability reduces further.

A low #z#-score means a very low probability of data below this #z#-score. The figure below shows the probability of #z#-score below #-2.5#.

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Probability for this is #0.62%# and note that if #z#-score falls further, area under the curve falls and probability reduces further.