Consider the following statements with respect to control charts for attributes
1. The lower control limit is non-negative
2. Normal distribution is the order for this data
3. The lower control limit is not significant
4. These charts give the average quality characteristics
Which of the statements given above are correct?
Option (A)
1, 2 and 3
Option (B)
2, 3 and 4
1, 3 and 4
1, 2 and 4
Correct Option:
Question Solution:
Control charts for attributes:
(i) It is attribute control i.e. for quality characteristics that can be classified as either conforming to the specifications. For example, dimensions checked by Go. No-Go gauge.
(ii) P.Chart : Fraction defective : Binomial distribution.
(iii) C-Chart : For defective : Poison distribution.