STAT 2040 - Assignment S7.xlsx - STAT 2040 Section 7 u2013...

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STAT 2040 Section 7 – Correlation and Regression Assignment Note: There will be two points possible per problem Problem 1 Ten pairs of data yield r = 0.003 and the regression equation y = 2 + 3x. Also, y-bar = 5.0. What is the best predicted value of y for x = 2? (Hint: Refer to Slide 21,22 and 31 in Section 7 slides) 6 8 2 A collection of paired data consists of the number of years that students have studied Spanish and their scores on a Spanish language proficiency test. A computer program was used to obtain the least squares linear regression line with the scores on the test as the dependent variable. The regression equation is: score-hat = 31.55 + 10.90*years R-squared = 83.0% What percentage of the total variation in test scores is UNEXPLAINED by the linear relationship between years of study and test scores? (hint: the unexplained variance would be 1 minus the explained variance, and the explained variance is represented by R-squared) 17% 3
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