The operations meager of?company that mamthctures tires wMts to deermine whether
ID: 3367199 • Letter: T
Question
The operations meager of?company that mamthctures tires wMts to deermine whether there are any differences-the quality of workmanship among the three daily shifts. She ngdenly selects 490 tires and caretily inspects them Each tire is eiher clasified as perfet, saniujlactory or dejective, and the shit that produced t s also recorded. The wo categocical varisables of iaterest are shift and coodition of the dire produced. The data can be mmarized by the accompanying two-way table Perfect Satisfactory Defective Total Shift 1 Shi 267 Sheft 336 total 1 210 1 278 A) This sample has degree of freedom DF II shih and quality are independest te B) Accuate to 2 decimal places, the epected count in row clmn 1 is ccurate to 2 decinal places, the component valer in wI column I of the table i NoExplanation / Answer
Solution:
A. DF = 4
B. E1,1 = 98.57
C. Component 1,1 = 0.72
D. X^2 = 12.07
E. P-value = 0.0168
Since p-value is less than 0.02 significance level, we reject Ho.
Yes.
Using megastat, the output
Col 1 Col 2 Col 3 Total Row 1 Observed 107 123 0 230 Expected 98.57 130.49 0.94 230.00 (O - E)² / E 0.72 0.43 0.94 2.09 Row 2 Observed 67 84 0 151 Expected 64.71 85.67 0.62 151.00 (O - E)² / E 0.08 0.03 0.62 0.73 Row 3 Observed 36 71 2 109 Expected 46.71 61.84 0.44 109.00 (O - E)² / E 2.46 1.36 5.44 9.25 Total Observed 210 278 2 490 Expected 210.00 278.00 2.00 490.00 (O - E)² / E 3.26 1.82 6.99 12.07 12.07 chi-square 4 df .0168 p-value