Copyright Malvin Porter, Jr. 2010 - acumen - The University of ...

A test for the Difference in Proportions tested the following null hypothesis: There is no
difference between the proportion of males and the proportion of females who selected
Aggressive Action Choices.
Of the 284 Best Action Choice responses selected by males, 68 were Aggressive Action
Choices (sample p = 0.239437). Of the 348 Best Action Choice responses selected by females,
76 were Aggressive Action Choices (sample p = 0.218391). The estimate of the difference
between male responses and female responses was 0.0210458. The hypothesized difference in
proportions of zero lies within the 95% CI (-0.0448896, 0.0869813) for the difference in
proportions between male responses and female responses to Aggressive Action Choices.
Therefore, zero is a plausible value for the difference in proportions between male responses and
female responses to Aggressive Action Choices. I conclude that there is no significant difference
in the proportion of male responses and the proportion of female responses to Aggressive Action
Choices. Therefore, I fail to reject the null hypothesis and I conclude that males were as likely to
choose Aggressive Action Choices as females. See Table 22.
Table 22
CBVS Test and Confidence Interval for the Proportion of Males and the Proportion of Females
who Selected Aggressive Action Choices
Sample ƒ n Sample p
Male 68 284 0.239437
Female 76 348 0.218391
Test of p = 0 vs. p ≠ 0
Difference = p (male) – p (female)
Estimate for difference: 0.0210458
95% CI (-0.0448896, 0.0869813)
Test for difference = 0 (vs. ≠ 0): Z = 0.63 P-Value = 0.532
Fisher's exact test: P-Value = 0.568
N = 632 responses
103