graphic interpretation

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graphic interpretation

by ash4gmat » Wed Dec 16, 2015 8:46 am
HI

Can someone help understand last 2 questions in this link from veritas.

https://www.veritasprep.com/sample-problems/?question=14

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by Marty Murray » Mon Dec 21, 2015 9:13 pm
As it stands, according to the graph, the relationship between S and L is the following. As S goes up, L, as indicated by the size of the circles, goes up as well. This is a positive correlation. As one goes up the other goes up.

So, in answer to the fourth question, if the relationship were inversed (Is that a word? Probably it should be reversed.), it would become the following. As S goes up, L goes down. So one would go up as the other goes down. That is how a negative correlation goes.

To answer the fifth question, you need to see that the relationship between F and S is not affected by changes in the relationship between L and S. The relationship between F and S is illustrated by the position of the circles, while L is illustrated by the size of the circles. In terms of the logic of what is going on, the relationship between F and S is the relationship between amount of fast-driving content and perception of sportiness. That relationship is unaffected by the answers to the separate question of how likely people are to buy the car.

From the graph we can see that as F increases S increases. So whether the relationship between L and S is positively or negatively correlated, the relationship between F and S remains positively correlated.
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