1. Defect by Units

In many situations, we are interested in estimating the occurrence rate of defective components per unit of measurement.

Example:

Consider a sugarcane harvesting machine where we will check the machine cab. Table 1 lists the types of defects, the units manufactured and the number of opportunities per defect. We will find confidence intervals for the cab product and also for each of its components.

Components	Unit	Defect	Opportunity
Tachometer	57	49	2
Hoses	57	29	2
Fence	57	18	6
Air Conditioning	57	14	1
Doors	57	10	2
Control box	57	6	1
Electrical System in the Panel	57	5	1
Control cables	57	3	2
Instrument	57	2	2
Ventilation	57	2	1
Column	57	1	1

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We will upload the data to the system.

Configure as shown in the figure below to perform the analysis.

Then click Calculate we obtain the results. You can also generate the analyses and download them in Word format.

The results are:

Quality indicator - DPU

	V1
Total PPM	912716.732
Total Yield	0.087
Total probability of defect	0.913
TOTAL SIGMA METRIC	0.000

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DPU Table

	DPU	Yield	Probability of Metric	SIGMA METRIC
Tachometer	0.860	0.423	0.577	0.000
Hoses	0.509	0.601	0.399	1.694
Fence	0.316	0.729	0.271	2.100
Air Conditioning	0.246	0.782	0.218	2.280
Doors	0.175	0.839	0.161	2.497
Control box	0.105	0.900	0.100	2.790
Electrical system in the panel	0.088	0.916	0.084	2.887
Control cables	0.053	0.949	0.051	3.139
Instrument	0.035	0.966	0.034	3.323
Ventilation	0.035	0.966	0.034	3.323
Column	0.018	0.983	0.017	3.613

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