Question

One criterion used to evaluate employees in the assembly section of a large factory is the number of defective pieces per 1,000 parts produced. The quality control department wants to find out whether there is a relationship between years of experience and defect rate. Since the job is repetitious, after the initial training period any improvement due to a learning effect might be offset by a loss of motivation. A defect rate is calculated for each worker in a yearly evaluation. The results for 100 workers are given in the table below. Years Since Training Period <1 Year 1-4 Years 5-9 Years High Defect Rate Average Low 7 Find the rejection region necessary for testing at the 10% level of significance whether there is a relationship between defect rate and years of experience using a Chi-square test. Select one: O Reject Ho if Xale < 7.779. Reject Ho if Xcale 9.488. Reject Ho if Xéale > 14.484. Reject Ho if X@ale < 16.919. Reject Ho if Xale > 9.488. Reject Ho if Xale > 7.779.

Answer 1

Sol Hoi there is no rate and relationship years of between defect experience HAI there is a relationship between defect rate and years of experience Test statistics el g Prij] ; för observed free, I eig- expected freq. eij- fi *fj:ti= sum of ith row PETALII Tilja eij + ) - I fj= sum of th columns t = over all sum & the rejection Region as Reject to if x > Xh & x² = x2 (2) tab. - 014) (CA) Harl er=3, C=3; 2=0.10

5 i. we Reject to of x² cal x² colo) (0) = 7.7794 so, Reject to lf to cal = 7.779