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The following data shows the age of peoplesurveyed (x) and each person's favoritenumber (y).What type of correlation does the data have?x 2 8 14 21 30y 35 9 3 24 7X 쉬A. PositiveB. NegativeC. None

The following data shows the age of peoplesurveyed (x) and each person's favoritenumber-example-1
User Kmort
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1 Answer

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We have two variables and we have to analyze which type of correlation they have, if there is any.

We can graph this data in order to see if there is correlation.

The graph of y(x) is:

There seems to be a tendency for smallest values of y when x increases, but it is debatable.

We will then calculate the correlation coefficient and then use this result to decide if there is correlation or not.

To calculate the correlation coefficient rxy in a sample, we apply:


r_(xy)={\frac{\sum_(i=1)^(n)(x_(i)-{\bar{x}})(y_(i)-{\bar{y}})}{{\sqrt{\sum_(i=1)^(n)(x_(i)-{\bar{x}})^(2)}}{\sqrt{\sum_(i=1)^(n)(y_(i)-{\bar{y}})^(2)}}}}

In this case, we are going to use software to calculate this correlation.

The result for this sample is rxy = -0.46.

This indicates there is a low degree negative correlation between x and y.

Answer: B. Negative.

The following data shows the age of peoplesurveyed (x) and each person's favoritenumber-example-1
User Carol McKay
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