Methods of quality improvement: the data set shows 72 samples (for

The data set shows  72 samples (for 72 hours) of size n=7 collected to test the production process of a filling machine for soft drink bottling.  The target filling is 20 fluid ounces.

Your tasks:

Select a random sample of 28 hours of data.  [Feel free to do it manually, if you cannot use the sample selection procedure in the software.]  Using the sample data, accomplish the following:

Part 1

1.     Construct an x–barchart.  Need to use graph paper.

2.     Calculate and plot the centerline and upper and lower control limits for the charts.

3.     Calculate and plot the A, B and C zone boundaries of the x-bar chart.   

4.     Plot the 24 sample means on the x-barchart.

5.     Based on x-bar findings, is the process under statistical control?  Explain and justify your answer.

Part 2

6.      Construct an R-chart. Need to use graph paper.

7.     Calculate and plot the centerline and upper and lower control limits for the charts.

8.     Calculate and plot the A, B and C zone boundaries of the R-chart.  

9.     Plot the sample ranges on the R-chart.

10.  Analyze the pattern of the R-chart.

11.  Based on R-chart findings, is the process under statistical control?  Explain and justify your answer.

Part 3

12.  Theoretically, what is the difference between x-bar chart and R-chart? Explain briefly.

13.  How are they used?  That is, what is their purpose? Explain briefly.

Part 4

14.  Compare the findings from your x-bar chart and R-chart.

15.  Explain why rational sub-groupings are used in constructing control charts?

16.  What are the major findings from the study? Explain briefly.

17.  What are your conclusions from the study?  Explain briefly.

Report:

Submit your findings and analysis in a report format.  

Feel free to contact me if you have questions.  Good Luck.