
Concept explainers
H0 or Ha? For each of the following hypotheses, explain whether it is a null hypothesis or an alternative hypothesis:
- a. For females, the population
mean on the political ideology scale is equal to 4.0. - b. For males, the population proportion who support the death penalty is larger than 0.50.
- c. The diet has an effect, the population mean change in weight being less than 0.
- d. For all Subway (submarine sandwich) stores worldwide, the difference between sales this month and in the corresponding month a year ago has a mean of 0.
a.

Identify whether the statement is null hypothesis or alternative hypothesis.
Answer to Problem 67CP
The given statement is null hypothesis.
Explanation of Solution
The given statement is that the population mean on the political ideology scale for female is equal to 4.
Null hypothesis:
It is a statement in which the parameter takes certain value and it is denoted as
Alternative hypothesis:
If the statement tells that the parameter falls in alternative range of values then it is termed as alternative hypothesis. It is denoted as
The value in the hypothesis generally represents no effect then the value in alternative hypothesis represents an effect of some type.
Here, the value in hypothesis represents no effect. That is, the population mean on the political ideology scale for female is equal to 4. Hence, the statement is null hypothesis.
b.

Identify whether the statement is null hypothesis or alternative hypothesis.
Answer to Problem 67CP
The given statement is Alternative hypothesis.
Explanation of Solution
It is given that the population proportion who support the death penalty is larger than 0.50.
Here, the hypothesis represents the greater than or larger than
c.

Identify whether the statement is null hypothesis or alternative hypothesis.
Answer to Problem 67CP
The given statement is Alternative hypothesis.
Explanation of Solution
It is given that the diet has an effect and the population mean change in weight is less than 0.
Here, the hypothesis represents the less than
d.

Identify whether the statement is null hypothesis or alternative hypothesis.
Answer to Problem 67CP
The given statement is null hypothesis.
Explanation of Solution
The given statement is that the difference between sales at current month and in the corresponding month a year ago is 0.
The value in the hypothesis generally represents no effect then the value in alternative hypothesis represents an effect of some type.
Here, the value in hypothesis represents no effect. That is, the population mean difference between sales at current month and in the corresponding month a year ago, is equal to 0. Hence, the given statement is a null hypothesis.
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Chapter 9 Solutions
Statistics: The Art and Science of Learning from Data (4th Edition)
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