Accompanying this problem set is an Excel file. On the first tab, are data that represent 50 periods where, for each period, 20 printed circuit boards are inspected for defects, with the number of defect opportunities per board is 4,250. For each period, what is provided is the total number of defects found (among all 20 boards). (20)
Using the data set, develop the dpmo and dpbo control charts using only the first 25 periods of data for the calculations, but plot all 100 data points. (If there are any out-of-control points in the first 25 periods, you don't need to remove them and you donâ€TMt need to recalculate the control limits). Out of all 60, note whether or not you suspect a process shift and, if so, the approximate location.
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Period
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#Def
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1
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1
|
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2
|
2
|
|
3
|
3
|
|
4
|
0
|
|
5
|
0
|
|
6
|
0
|
|
7
|
4
|
|
8
|
4
|
|
9
|
3
|
|
10
|
1
|
|
11
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0
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12
|
2
|
|
13
|
0
|
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14
|
2
|
|
15
|
1
|
|
16
|
1
|
|
17
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4
|
|
18
|
1
|
|
19
|
1
|
|
20
|
2
|
|
21
|
1
|
|
22
|
1
|
|
23
|
1
|
|
24
|
1
|
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25
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1
|
|
26
|
2
|
|
27
|
0
|
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28
|
1
|
|
29
|
2
|
|
30
|
1
|
|
31
|
1
|
|
32
|
0
|
|
33
|
1
|
|
34
|
1
|
|
35
|
2
|
|
36
|
1
|
|
37
|
2
|
|
38
|
2
|
|
39
|
1
|
|
40
|
0
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41
|
2
|
|
42
|
1
|
|
43
|
2
|
|
44
|
2
|
|
45
|
1
|
|
46
|
3
|
|
47
|
1
|
|
48
|
1
|
|
49
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5
|
|
50
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0
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|
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SHOW ALL WORK