September 11, 2012
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A relationship refers to the correspondence
between two variables.
two ways to view the relationship: the nature
of the relationship or the pattern of it.
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Some pairs of variables are related positively.
This means that as one variable goes up, the
other tends to go up as well.
For example, height and weight are positively
related because taller people tend to be
heavier.
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Also known as an inverse relationship
negatively related, which means that as one
goes down the other tends to go up.
y, decreases as another, say x, increases.
For example, gas mileage and the weight of a
car are negatively related, because heavier
cars tend to get lower mileage.
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no pattern
scattered
This means the two
are not related.
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Size shoe a baseball player
wears and their batting
average
Not related because the
shoe size does not make the
player better or worse, then
are not related.
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Two variables may be related linearly. This
means that a straight line can represent their
relationship.
For example, the amount of paint needed to
paint a wall is linearly related to the area of
the wall.
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nonlinear:relationships cannot be represented
by a straight line.