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What is the correlation coefficient for the data shown in the table?

R =

What is the correlation coefficient for the data shown in the table? R =-example-1
User Jay Adams
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2 Answers

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As the data makes a linear function, y = -x + 15, the correlation coefficient would be r = -1, as the function is negative.

Hope this helps!
User Helge Becker
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The correct answer is:

-1.

Step-by-step explanation:

When we graph this data, we can see it seems to form a straight line. To check this, we find the slope of the data using the formula


m=(y_2-y_1)/(x_2-x_1)

Using the first two points, we have:


m=(10-15)/(5-0)=(-5)/(5)=-1

Checking the next two points, we have:


m=(5-10)/(10-5)=(-5)/(5)=-1

Since the slope is the same between successive pairs of points, this is a linear data set.

This means the linear regression will go through every point, and will be a perfect fit. The correlation coefficient, r, of a data set is 1 if it is a perfect positive fit and -1 if it is a perfect negative fit; since the slope is decreasing, this is a negative correlation, and since it fits perfectly, it is -1.

User Louis Yang
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