Use statistical software to analyze the relationship between students GPA andtheir IQ

Chapter 0, Problem 28.49

(choose chapter or problem)

Use statistical software to analyze the relationship between students GPA andtheir IQ, self-assessed school status (C2), and self-assessed popularity (C5).(a) One observation is an extreme outlier when all three explanatory variablesare used. Which observation is this? Give the observation number and explainhow you found it using regression output. Find this observation in the data list.What do you see that is unusual about it?(b) Software packages often identify unusual or influential observations. Haveany observations been identified as unusual or influential? If so, identify thesepoints on a scatterplot of GPA versus IQ. (c) C2 (school status) is the aspect of self-concept most highly correlated toGPA. If we carried out the simple linear regression of GPA on C2, what percentof the variation in students GPAs would be explained by the straight-linerelationship between GPA and C2?(d) You know that IQ is associated with GPA, and you are not studying thatrelationship. Because C2 and IQ are positively correlated (r = 0.547), asignificant relationship between C2 and GPA might occur just because C2 canstand in for IQ. Does C2 still contribute significantly to explaining GPA afterwe have allowed for the relationship between GPA and IQ? (Give a test statistic,its P-value, and your conclusion.)(e) A new student in this class has IQ 115 and C2 score 14. What do you predictthis students GPA to be? (Just give a point prediction, not an interval.)