Question 1

The mean age of bus drivers in Chicago is greater than 54.4 years. If a hypothesis test is performed, how should you interpret a decision that fails to reject the null hypothesis?

Accepted Answer

Failing to reject the null hypothesis means there isn't enough evidence to support the alternative hypothesis, which in this context is the claim that the mean age is greater than 54.4 years.

Question 2

A candidate for governor of a certain state claims to be favored by at least half of the voters. If a hypothesis test is performed, how should you interpret a decision that fails to reject the null hypothesis?

Accepted Answer

Failing to reject the null hypothesis means there is not enough statistical evidence to refute the claim, which in this context is that the candidate is favored by at least half of the voters.

Question 3

The mean score for all NBA games during a particular season was less than 90 points per game. Identify the
type I and type II errors for the hypothesis test of this claim.

Accepted Answer

The answer of The mean score for all NBA games...

Question 4

The mean age of bus drivers in Chicago is 51.3 years. Identify the type I and type II errors for the hypothesis
test of this claim.

Accepted Answer

The answer of The mean age of bus drivers in...

Question 5

The mean score for all NBA games during a particular season was less than 104 points per game. If a hypothesis test is performed, how should you interpret a decision that fails to reject the null hypothesis?

Accepted Answer

The answer of The mean score for all NBA games...

Question 6

The mean score for all NBA games during a particular season was less than 104 points per game. If a hypothesis test is performed, how should you interpret a decision that rejects the null hypothesis?

Accepted Answer

Rejecting the null hypothesis means that there is sufficient evidence to support the alternative hypothesis, which is that the mean score is less than 104 points per game.

Question 7

The mean IQ of statistics teachers is greater than 130. Identify the type I and type II errors for the hypothesis
test of this claim.

Accepted Answer

The answer of The mean IQ of statistics teachers is...

Question 8

The mean IQ of statistics teachers is greater than 110. If a hypothesis test is performed, how should you interpret a decision that fails to reject the null hypothesis?

Accepted Answer

CA decision that fails to reject the null hypothesis means there is not enough evidence to support the alternative hypothesis. In this context, it indicates there is not sufficient evidence to conclude that the mean IQ of statistics teachers is greater than 110.

Question 9

The mean IQ of statistics teachers is greater than 130. If a hypothesis test is performed, how should you interpret a decision that rejects the null hypothesis?

Accepted Answer

Rejecting the null hypothesis in this context means that the data provides sufficient evidence to support the alternative hypothesis, which is that the mean IQ of statistics teachers is greater than 130.

Question 10

A candidate for governor of a certain state claims to be favored by at least half of the voters. Identify the type I
and type II errors for the hypothesis test of this claim.

Accepted Answer

The answer of A candidate for governor of a certain...

Question 11

The owner of a professional basketball team claims that the mean attendance at games is over 22,000 and therefore the team needs a new arena. Determine whether the hypothesis test for this claim is left-tailed,
Right-tailed, or two-tailed.

Accepted Answer

The hypothesis test is right-tailed because the claim is about the mean attendance being greater than a specific value (22,000), which suggests looking for values to the right of the mean in the distribution.

Question 12

An elementary school claims that the standard deviation in reading scores of its fourth grade students is less than 3.75. Determine whether the hypothesis test for this claim is left-tailed, right-tailed, or two-tailed.

Accepted Answer

The hypothesis is testing if the standard deviation is less than a specific value, which indicates a left-tailed test.

Question 13

A car maker claims that its new sub-compact car gets better than 49 miles per gallon on the highway. Determine whether the hypothesis test for this is left-tailed, right-tailed, or two-tailed.

Accepted Answer

The hypothesis is testing if the mileage is greater than a certain value (49 miles per gallon), which means we are looking at values to the right of 49 on the number line, making it a right-tailed test.

Question 14

A candidate for governor of a certain state claims to be favored by at least half of the voters. If a hypothesis test is performed, how should you interpret a decision that rejects the null hypothesis?

Accepted Answer

Rejecting the null hypothesis means the data provides sufficient evidence against the null hypothesis, which in this context is the claim that at least half of the voters favor the candidate.

Question 15

The mean age of bus drivers in Chicago is 50.3 years. If a hypothesis test is performed, how should you interpret a decision that fails to reject the null hypothesis?

Accepted Answer

Failing to reject the null hypothesis means there is not enough statistical evidence to refute the claim that the mean age is 50.3 years, not that it necessarily supports the claim.

Question 16

The dean of a major university claims that the mean time for students to earn a Masterʹs degree is at most 4.1 years. If a hypothesis test is performed, how should you interpret a decision that fails to reject the null
Hypothesis?

Accepted Answer

Failing to reject the null hypothesis means there isn't enough evidence to support a conclusion that contradicts the null hypothesis, which in this case is the claim that the mean time to earn a Master's degree is at most 4.1 years.

Question 17

The dean of a major university claims that the mean time for students to earn a Masterʹs degree is at most 3.5 years. If a hypothesis test is performed, how should you interpret a decision that rejects the null hypothesis?

Accepted Answer

Rejecting the null hypothesis means there is sufficient evidence to conclude that the mean time to earn a Master's degree is more than 3.5 years, contradicting the dean's claim.

Question 18

The mean age of bus drivers in Chicago is greater than 54.1 years. If a hypothesis test is performed, how should you interpret a decision that rejects the null hypothesis?

Accepted Answer

Rejecting the null hypothesis in this context means that the data provides sufficient evidence to support the alternative hypothesis, which is that the mean age of bus drivers in Chicago is greater than 54.1 years.

Question 19

A brewery claims that the mean amount of beer in their bottles is at least 12 ounces. Determine whether the hypothesis test for this claim is left-tailed, right-tailed, or two-tailed.

Accepted Answer

The hypothesis test is left-tailed because the claim is testing if the mean amount is less than 12 ounces, which would be a concern for the brewery.

Question 20

The mean age of bus drivers in Chicago is 51.5 years. If a hypothesis test is performed, how should you interpret a decision that rejects the null hypothesis?

Accepted Answer

Rejecting the null hypothesis means there is sufficient evidence to conclude that the mean age is not equal to 51.5 years, thus rejecting the claim that μ = 51.5.

Quiz 7: Hypothesis Testing With One Sample