Instructions for Exercises 12.2 and 12.3:
(b) Make an Excel worksheet to calculate SSxx , SSyy , and SSxy . Use these sums to calculate the sample correlation coefficient. Check your work by using Excel's function =CORREL(array1,array2).
(c) Use Appendix D to find t.05 for a two-tailed test for zero correlation.
(d) Calculate the t test statistic. Can you reject ρ = 0? (e) Use Excel's function =TDIST(t,deg_freedom,tails) to calculate the two-tail p-value.
Chapter 12 Bivariate Regression 497
12.2 Part-Time Weekly Earnings ($) by College Students WeekPay
Hours Worked (X) Weekly Pay (Y)
12.3 Data Set Telephone Hold Time (min.) for Concert Tickets CallWait
Operators (X) Wait Time (Y)
The solution provides step by step method for the calculation of sum of squares of x and y, sample correlation and test statistic for significance of correlation coefficient. Formula for the calculation and Interpretations of the results are also included.