There would be a negative correlation in the classroom, of a student's grades, with the number of days absent from class.
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A positive correlation means as the first goes up, so does the second. A negative correlation means as the first goes up, the second goes down. Examples of positive correlations:
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A real life example of a positive correlation is that we find
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In an absolute sense you cannot have fewer than 0 apples. If you are in debt to someone for an apple (perhaps they gave you one and you ate it) you may say you have 1 apples, but
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