9.docxThe paired data below consists of test scores and hours of preparation for 5 randomly selected students.
x Hours of preparation 5 2 9 6 10
y Test score 64 48 72 73 80
1. Use the given data to find the correlation coefficient r, regression equation and scatter plot in MS Excel.
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2. Based on the linear correlation coefficient r, is this a good model? Explain.
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3. What is the best predicted test score for a student who spent 7 hours preparing for the test?
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5. Find the 99% prediction interval for the test score of a person who spent 7 hours preparing for the test given that E = 34.677. Interpret the result.
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6. Find the explained variation.
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7. Find the unexplained variation.
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8. Find the total variation.
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9. Find the value of r2 and explain its meaning.
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10. If the data point ( 3, 100) is added to the data set, how would this effect the results of the regression analysis? Is this data point an outlier, influential point or both? Explain.
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