Chapter 9 assign.
Suppose you are performing a hypothesis test on μ and the value of σ is known. At the 10% significance level, the critical value(s) for a left-tailed test is (are):
-z0.10
Suppose a hypothesis test is conducted at the α=0.05 level, the null would be rejected for p-values between
0 and 0.05
Which of the the following signs in the null would indicate a left-tailed test?
> Reason: The null cannot have < or >. = Reason: This would be a two-tailed test. ≤ Reason: This would be a one right-tailed test. ≥ Reason: The alternative would be <, which makes it a left-tailed test. ≥ answer
Suppose you are performing a hypothesis test on μ and the value of σ is known. At the 10% significance level, the critical value(s) for a right-tailed test is (are):
z0.10
Suppose you are performing a hypothesis test on μ and the value of σ is known. At the 10% significance level, the critical value(s) for a two-tailed test is (are):
-z0.05 and z0.05
Which of the the following signs in the null would indicate a two-tailed test?
=
The null hypothesis is specified by using the following signs:
=, ≤, or ≥
Which of the the following signs in the null would indicate a left-tailed test?
> Reason: The null cannot have < or >. = Reason: This would be a two-tailed test. ≤ Reason: This would be a one right-tailed test. ≥ Reason: The alternative would be <, which makes it a left-tailed test.
Which of the following statements is NOT correct concerning the p-value and critical value approaches to hypothesis testing?
Both approaches use the same decision rule concerning when to reject H0.
Which one of the following is NOT a step we use when formulating the null and alternative hypotheses?
Calculate the value of the sample statistic.
A Type II error occurs when we
Do not reject the null hypothesis when it is actually false.
When H0: μ ≥ 150 and x = 125, the p-value is defined as
P(x ≥125).
If the collected sample data is inconsistent with what is stated in the null hypothesis, which decision is made?
The null is rejected and the alternative is accepted.
True or false: The test statistic for p is valid only if ¯P approximately follows a normal distribution.
True
The significance level is the allowed probability of making
a Type I error.
The conclusions of a hypothesis test that are drawn from the p-value approach versus the critical value approach are
always the same.
For a given sample size n, α can only be reduced
at the expense of increasing β.
The alternative hypothesis typically
contests the status quo and may suggest a corrective action if true.
A test of H0: μ = 10 at the α significance level can be rejected if a 100(1-α)% confidence interval for μ
does not include 10.
Order the steps of formulating the competing hypotheses:
identify, determine, include
We can generally reduce both Type I and Type II errors simultaneously by
increasing the sample size.
If the value of the test statistic falls in the rejection region, then the p-value must be
less than α.
A binomial distribution can be approximated by a ______ distribution for large sample sizes.
normal
The normal distribution approximation for a binomial distribution is valid when
np ≥ 5 and n(1 - p) ≥ 5
The p-value is calculated assuming the
null hypothesis is true.
The hypothesis denoted by H0 is the ______ hypothesis and the hypothesis denoted by HA is the ______ hypothesis.
null, alternative
When performing a hypothesis test on μ when σ is known, H0 can be rejected for which of the following case?
p-value < α
We can reject the null hypothesis when the
p-value < α.
When H0: μ =12 and x = 10, the p-value is defined as
p-value = 2 × P(Z ≤ z)
Unlike the mean and standard deviation, the population proportion p is a descriptive summary measure that can be used for data that are ______.
qualitative
In hypothesis testing, if the sample data provide significant evidence that the null hypothesis is incorrect, then we
reject the null hypothesis.
If the chosen significance level is α = 0.05, then there is a 5% chance of
rejecting a true null hypothesis.
The critical value approach specifies a region of values, called the ______. If the test statistic falls into this region, we reject the ______.
rejection region, null hypothesis
When testing μ and σ is known, H0 can never be rejected if z ≤ 0 for a
right-tailed test.
For a hypothesis test on μ when the value of σ is unknown, the value of the test statistic is calculated as ______, provided that we sample from a normal population.
tdf = x−μ0s/s√n
When performing a hypothesis test on μ when the value of σ is unknown, the test statistic is computed as x−μ0s/√n and it follows the
tdf distribution with (n - 1) degrees of freedom.
The basic principle of hypothesis testing is to assume that
the null hypothesis is true and see if the sample data contradict this assumption.
The proportion would be the appropriate descriptive measure when trying to estimate the
the percentage of students living off-campus.
All of the following are approaches to implementing a hypothesis test EXCEPT:
the sample test
The critical value of a hypothesis test is
the value that separates the rejection region from the non-rejection region.
For a hypothesis test concerning the population proportion p, the value of the test statistic is calculated as
z = p−p0√p0(1−p0)n
Which of the following is true?
α = the probability of committing a Type I error; β = the probability of committing a Type II error.
We do NOT reject the null hypothesis when the p-value is
≥ α
A 100(1-α)% confidence interval can be used to test which types of hypotheses tests?
A two-tailed test at the α significance level.