Question

Exercise 15-28 (LO015-6) Four brands of lightbulbs are being considered for use in the final assembly area of the Ford F-150 truck plant in Dearborn, Michigan. The director of purchasing asked for samples of 120 from each manufacturer, The numbers of acceptable and unacceptable bulbs from each manufacturer are shown below. At the 0.01 significance level, is there a difference in the quality of the bulbs? Manufacturer A C Unacceptable Acceptable 11 6 109 111 114 111 Total 120 120 120 120 Click here for the Excel Data File Ha There is no relationship between quality and manufacturer. h There is a relationship. State the decision rule using 0.01 significance level. (Round your answer to 3 decimal places.) Reject HO if chi-square > Compute the value of chi-square. (Round your answer to 3 decimal places.) Chi-square value

Answer 1

The statistical software output for this problem is:

Contingency table results: Rows: var3 Columns: None A B C D Total Unacceptable 11 9 6 9 35 Acceptable 109 111 114 111 445 Total 120 120 120 120 480 Chi-Square test: Statistic DF Value Chi-square 3 1.5717496 P-value 0.6658

Hence,

Decision rule: Reject Ho if chi-square > 11.345

Chi-square value = 1.572