| Software Output Summary
data from the previous example
Margin
of Error for Proportions
n
= 500 Proportion = 0.23 Standard Error = 0.0188
Margin
Limits
Confidence Error +/-
Lower
Upper
------------------------------------------------------------
90%
0.0311 0.1989 0.2611
95%
0.0369 0.1931 0.2669
99%
0.0486 0.1814 0.2786
Summary
Table of Margin of Errors for each proportion
(converted
to %)
The
promotion system is … |
Staff |
+/-
Margin of Error |
95%
CI |
Fair |
50% |
9.8% |
40.2%
- 59.8% |
Sometimes
Fair |
30% |
8.9% |
21.0%
– 38.9% |
Not Fair |
20%
|
7.8% |
12.2%
– 27.8% |
Count
(n) |
100 |
|
|
I am 95% confident the percent of all
staff in the population who believe the promotion system is not fair is between 12.2% to
27.8%.
|
