Fundamentals of Probability and Statistics for Engineers

and 100 daily output readings are taken, as shown in Table 10.7. On the basis of

this sample, does the second production line behave in the same statistical manner

as the first? U se

10.5 In a given plant, a sample of a given number of production items was taken from
each of the five production lines; the number of defective items was recorded, as
shown in Table 10.8. Test the hypothesis that the proportion of defects is constant
from one production line to another. Use

10.6 We have rejected in Example 10.2 the Poisson distribution with
basis of accident data at the 1% significance level. At the same :
(a) Would a Poisson distribution with estimated from the data be acceptable?
(b) Would a negative binomial distribution be more appropriate?

10.7 The data on the number of arrivals of cars at an intersection in 360 10 s intervals
are as shown in Table 10.9.
Three models are proposed:
model 1:

Table 10.7 Production-line data for Problem 10.4

Daily output interval Number of occurrences

< 4 000 3

4 000–5 000 3

5 000–6 000 7

6 000–7 000 16

7 000–8 000 27

8 000–9 000 22

9 000–10 000 11

10 000–11 000 8

11 000–12 000 2

> 12 000 1

n 100

Table 10.8 Production-line data for Problem 10.5

Production line Number of defects

111

213

39

412

58

M odel Verification 331

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