Concept explainers
In Exercises 1–5, use the following survey results: Randomly selected subjects were asked if they were aware that the Earth has lost half of its wildlife population during the past 50years. Among 1121 women, 23% said that they were aware. Among 1084 men, 26% said that they were aware (based on data from a Harris poll).
1. Biodiversity Identify the null and alternative hypotheses resulting from the claim that for the people who were aware of the statement, the proportion of women is equal to the proportion of men.
To identify: The null and alternative hypotheses.
Answer to Problem 1CQQ
Null hypothesis:
Alternative hypothesis:
Explanation of Solution
Given info:
The claim for the hypothesis test is that the proportion of women is equal to the proportion of mean.
Justification:
Let population 1 denotes the women and population 2 denote the men.
Let
Here, the given claim is the proportion of women is equal to the proportion of men. This indicates that
Null hypothesis:
That is, the proportion of women is equal to the proportion of men.
Alternative hypothesis:
That is, the proportion of women differs from the proportion of men
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Chapter 9 Solutions
Elementary Statistics (13th Edition)
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