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# Correlation and Regression

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Listed below are measures of pain intensity before and after using the proprietary drug Duragesic.

The data are listed in order by row, and corresponding measures are from the same subject before and after the treatment. For example, the first subject had a measure of 1.2 before the treatment and a measure of 0.4 after the treatment.

PAIN INTENSITY BEFORE TREATMENT
1.2 1.3 1.5 1.6 8.0 3.4 3.5 2.8 2.6 2.2 3.0 7.1 2.3 2.1 3.4 6.4 5.0 4.2 2.8 3.9 5.2 6.9 5.0
5.5 6.0 5.5 8.6 9.4 10.0 7.6

PAIN INTENSITY AFTER TREATMENT
0.4 1.4 1.8 2.9 6.0 1.4 0.7 3.9 0.9 1.8 0.9 9.3 8.0 6.8 2.3 0.4 0.7 1.2 4.5 2.0 1.6 2.0 2.0
6.8 6.6 4.1 4.6 2.9 5.4 4.8 4.1

1. Use the data to construct a scatter plot, then test for a linear correlation between pain intensity before and after the treatment. If there is a significant linear correlation, does it follow that the drug treatment is effective?

2. Find the equation of the regression line. Let the response (y) variable be the pain intensity after the treatment. What would be the equation of the regression line for a treatment having absolutely no effect?

https://brainmass.com/statistics/pearson-product-moment-correlation/correlation-and-regression-110279

#### Solution Summary

Finds correlation between pain intensity before and after the treatment. Also finds a regression equation using the pain intensity before treatment as the independent variable and pain intensity after the treatment as response (Y) variable.

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