Answer Happy

A researcher wants to compare the wage among people working in three industries: manufacturing, construction, and others. Let Amanufacturing, Mconstruction , and Mother denote the population mean wage of the three industries. A random sample of 100 people from each of the industries is obtained. The summary statistics of these three samples are shown in the following table: Sample Size Sample Mean Sample SD 100 9.6 5.4 Manufacturing Construction 100 9.4 3.2 Other 100 8.5 4.6 The ANOVA test indicates that there are some differences among the mean wages of the three industries. We want to construct Bonferroni 91% simultaneous confidence intervals for all the pairwise differences of the mean wage. Which one of the following formulas gives the confidence interval for Humanufacturing – Moconstruction ? 19 (9.6 - 9.4) – 1797 V 100 . where 8 = 9.3.27+99.4.6°+99.5.4 297 and t997 is obtained from the t distribution with degrees of freedom 297 corresponding to confidence level 97%. 100 O 99.3.2? +994.699.5.4 (9.6 – 9.4) +639781/100 + Too , where s 297 and t;97 is obtained from the t distribution with degrees of freedom 297 corresponding to confidence level 91%. (9.6 - 9.4) 1198 V 100 99-3.22 +99-5.4 + 100, where s = and tie is obtained from the distribution with degrees of freedom 198 corresponding to confidence level 91%. 198 (9.6 – 9.4) + ti98 8V 100 99.3.2 +99-5.42 + 100, where 8 = 198 and Ci9g is obtained from the distribution with degrees of freedom 198 corresponding to confidence level 97%.