
Quality in Procurement 429
left-hand side of the graph� The intersection of this line with the scale on
the right-hand side of the graph gives Pa = 0�94� Because designing the SSP
is equivalent to nding the value of (n, c) that is common to two given
values of (p, Pa(p)), the graph can be used to design SSPs, as shown in the
following example�
Nomograph of the cumulative binomial distribution
.01
5
0
1000
700
500
400
300
200
140
100
70
50
40
30
20
10
5
2
Occurrences (c)
10
20
30
40
50
70
100
140
200
.02
.001
.005
.01
.02
.05
.10
.20
.30
.40
.50
.60
.70
.80
.90
.95
.98
.99
.995
.999
.03
.04
.05
0
1
2
3
4
5
7
9
.06
.07
Probability of occurrence in a single trial (p)
Probability of c or fewer occur ...