In: Statistics and Probability
A popular theory is that presidential candidates have an advantage if they are taller than their main opponents. Listed are heights (in centimeters) of randomly selected presidents along with the heights of their main opponents. Complete parts (a) and (b) below.
Height (cm) of President Height (cm) of Main
Opponent
179 166
182 173
173 175
191 174
192 180
182 175
a. Use the sample data with a
0.050.05
significance level to test the claim that for the population of heights for presidents and their main opponents, the differences have a mean greater than 0 cm.In this example,
mu Subscript dμd
is the mean value of the differences d for the population of all pairs of data, where each individual difference d is defined as the president's height minus their mainopponent's height. What are the null and alternative hypotheses for the hypothesis test?
Upper H 0H0:
mu Subscript dμd
▼
not equals≠
equals=
greater than>
less than<
nothing cm
Upper H 1H1:
mu Subscript dμd
▼
not equals≠
greater than>
less than<
equals=
nothing cm
(Type integers or decimals. Do not round.)
Identify the test statistic.
tequals=nothing
(Round to two decimal places as needed.)
Identify the P-value.
P-valueequals=nothing
(Round to three decimal places as needed.)
What is the conclusion based on the hypothesis test?
Since the P-value is
▼
less than or equal to
greater than
the significance level,
▼
reject
fail to reject
the null hypothesis. There
▼
is
is not
sufficient evidence to support the claim that presidents tend to be taller than their opponents.
b. Construct the confidence interval that could be used for the hypothesis test described in part (a). What feature of the confidence interval leads to the same conclusion reached in part (a)?
The confidence interval is
nothing
cmless than<mu Subscript dμdless than<nothing
cm.
(Round to one decimal place as needed.)
What feature of the confidence interval leads to the same conclusion reached in part (a)?
Since the confidence interval contains
▼
only positive numbers,
zero,
only negative numbers,
▼
reject
fail to reject
the null hypothesis.
Enter your answer in each of the answer boxes.