_ A researcher tested whether time of day could predict mood in a sample of 19 college students. If Wu, then what is the standard error of estimate in this sample? 3' Recall that the standard error of estimate is the square root of MSresidual. - To test whether extracurricular activity is a good predictor of college success, a college administrator records whether students participated in extracurricular activities during high school and their subsequent college freshman GPA. siss a sisisis a \" l 5332' (a) Code the dichotomous variable and then compute a point-biserial correlation coefcient. (Round your answer to three decimal places.) |:| (b) Using a two-tailed test at a 0.05 level of signicance, state the decision to retain or reject the null hypothesis. Hint: You must rst convert rto a tstatistic. a} Retain 1he null I'rypmheeie. L3 Reject the null hypothesis. You may need to use the appropriate table in Appendix B to answer this