Question

In: Statistics and Probability

A plant manager is interested in developing a quality-control program for an assembly line that produces...

A plant manager is interested in developing a quality-control program for an assembly line that produces light bulbs. To do so, the manager considers the quality of the products that come from the line. The light bulbs are packed in boxes of 12, and the line produces several thousand boxes of bulbs per day. To develop baseline data, workers test all the bulbs in 100 boxes. They obtain the following results:

Defective Bulbs/Box Boxes
0 68
1 27
2 3
3 2

Run @RISK’s distribution fitting procedure on the preceding data choosing Discrete Sample Data (Counted Format) for the type of data.

a. The Fit Results window shows that the Poisson is the best fitting theoretical distribution. Is the Poisson a good choice? Why or why not? What is the interpretation of the parameter for the Poisson in this setting?

b. Noticing that there are only two boxes with three defective bulbs, you combine the last two categories in the preceding data. Rerunning @RISK’s fitting procedure, we see that the binomial now fits best according to the Chi-Square measure, with the Poisson coming in a close second. How much has the parameter (m) for the Poisson changed from the case with four categories? Is there a reasonable interpretation of the parameters n and p for the binomial in this setting?

c. Which distribution would you use if you were the plant manager? Why?

Solutions

Expert Solution


Related Solutions

Problem: A plant manager is interested in developing a quality-control program for an assembly line that...
Problem: A plant manager is interested in developing a quality-control program for an assembly line that produces light bulbs. To do so, the manager considers the quality of the products that come from the line. The light bulbs are packed in boxes of 12, and the line produces several thousand boxes of bulbs per day. To develop baseline data, workers test all the bulbs in 100 boxes. They obtain the following results: No. of Defective Bulbs/Box No. of Boxes 0...
As the quality control manager at a plant that produces cereal, you would like to ensure...
As the quality control manager at a plant that produces cereal, you would like to ensure that the average amount of cereal being put in each box is 455g. A random sample is contained below (this sample is also contained in the DATA 2 tab of the downloaded Excel file). At a 5% significance level, can you conclude that the average fill level is different than 455g? Cereal Box Fill Levels 451.48 453.62 452.03 455.14 457.1 455.61 458.61 458.96 452.53...
You are the quality assurance person working an assembly line at a TV manufacturing plant. They...
You are the quality assurance person working an assembly line at a TV manufacturing plant. They produce 1000 TV’s a day. IF THE TV’S ARE ALL THE SAME MODEL, WHAT PERCENTAGE (think about the cost of testing) WOULD YOU TEST (WHY?) AND HOW WOULD YOU SELECT THEM (Don’t just say “randomly” – How do you do it randomly?) If the inspector were lazy, how would they likely do it as a “convenience” sample? Lastly, if the 1000 TV’s were 4...
A quality control manager at a plant wants to determine if the average width of bolts...
A quality control manager at a plant wants to determine if the average width of bolts is different than 4 mm. A sample of 28 bolts yields sample mean,  mm and sample standard deviation, s = 0.6. The decision with α = 0.05 would be:
The quality-control manager of a Long John Silver's restaurant is interested in improving the speed at...
The quality-control manager of a Long John Silver's restaurant is interested in improving the speed at which cars get through the drive-through lane. According to records obtained from the restaurant, it is determined that the mean time that drivers wait at the drive-through window is 59.3 seconds with a standard deviation of 13.1 seconds. The distribution of time at the window is skewed right. Consider random samples of size n = 40 from the population of drive-through wait times. What...
As part of the quality-control program for a catalyst manufacturing line, the raw materials (alumina and...
As part of the quality-control program for a catalyst manufacturing line, the raw materials (alumina and a binder) are tested for purity. The process requires that the purity of the alumina is to be 85%. A random sample from a recent shipment of alumina yielded the following results (in %):            93.2               87.0               92.1                      90.1               87.3               93.6 a) Test the requirements of the catalyst manufacturing line using the appropriate hypothesis test (assume a=0.05). b) Verify your result in part...
A company produces tires for passenger cars. The quality control manager tells the company president that...
A company produces tires for passenger cars. The quality control manager tells the company president that the proportion of defects is less than 1%. A sample of 36 tires reveals a defect rate of 1.8%. Is there evidence that the quality control manager is lying? Use a .05 level of significance
A quality control manager suspects that the quality of items that are manufactured on a Monday...
A quality control manager suspects that the quality of items that are manufactured on a Monday is better than that of items manufactured on a Wednesday. In a random sample of 400 items manufactured on a Monday, 370 were rated acceptable or better, and in a random sample of 300 items manufactured on Wednesday, 260 were rated as acceptable or better. Can you conclude that the true proportion of items rated acceptable or better is greater on Monday than on...
MaxFlight produces golf balls with a mean driving distance of 295 yards. Its quality control program...
MaxFlight produces golf balls with a mean driving distance of 295 yards. Its quality control program involves taking periodic samples of 50 golf balls to monitor the manufacturing process. Quality assurance procedures call for the continuation of the process if the sample results are consistent with the assumption that the mean driving distance for the population of golf balls is 295 yards; otherwise the process will be adjusted. Assume that a sample of 50 golf balls provided a sample mean...
A production line produces monitors, 7% of which have cosmetic defects. A quality manager randomly selects...
A production line produces monitors, 7% of which have cosmetic defects. A quality manager randomly selects 7 monitors from the production line and is interested in the number of defective parts found. For questions 2-9 compute the probability for the number of monitors that have a cosmetic defect. (Use 5 decimal places for your answers): Table 01 x f (x) 0 x0 1 x1 2 x2 3 x3 4 x4 5 x5 6 x6 7 x7 Compute the probability for...
ADVERTISEMENT
ADVERTISEMENT
ADVERTISEMENT