Correlation and Regression Analysis

Module 5 Homework Assignment

The paired data below consists of test scores and hours of preparation for 5 randomly selected students. Use this data set to answer the questions below:

xHours of preparation529610

y Test score 6448727380

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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4.Find the standard error . Use formula or MS Excel.

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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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