Quiz
Chapter 8
Crie uma conta grátis para terminar este quiz
Salve seu progresso e veja sua nota final.
Já tem uma conta? Inicie sessão
Perguntas do quiz (19)
1A sample of n = 16 individuals is selected from a population with μ = 40 and σ = 12, and a treatment is administered to the sample. After treatment, the sample mean is M = 42. How does this sample compare to samples that should be obtained if the treatment has no effect?
- AIt is an extreme value that would be very unlikely if the treatment has no effect.
- BIt is much the same as samples that would be obtained if the treatment has no
effect. - CThe mean is noticeably larger than would be expected if the treatment has no
effect but it is not quite an extreme sample. - DThere is no way to compare this sample with those that would be obtained if the
treatment had no effect.
2A researcher selects a sample of n = 20 from a normal population with μ = 80 and σ = 20, and a treatment is administered to the sample. If a hypothesis test is used to evaluate the effect of the treatment, what is the null hypothesis?
- Aμ = 80
- BM = 80
- Cμ ≠ 80
- DM ≠ 80
3What is the correct decision in a hypothesis if the data produce a z-score that is in the critical region?
- AReject H0
- BFail to reject H0
- CReject H1
- DFail to reject H1
4A researcher administers a treatment to a sample of n = 25 participants and uses a hypothesis test to evaluate the effect of the treatment. The hypothesis test produces a z-score of z = 1.77. Assuming that the researcher is using a two-tailed test,
- AThe researcher should reject the null hypothesis with α = .05 but not with α = .01.
- BThe researcher should reject the null hypothesis with either α = .05 or α = .01.
- CThe researcher should fail to reject H0 with either α = .05 or α = .01.
- DCannot answer without additional information.
5When does a researcher risk a Type I error?
- Aanytime H0 is rejected
- Banytime H1 is rejected
- Canytime the decision is “fail to reject H0”
- DAll of the other options are correct.
6Which of the following defines a Type II error?
- Arejecting a false null hypothesis
- Brejecting a true null hypothesis
- Cfailing to reject a false null hypothesis
- Dfailing to reject a true null hypothesis
7What is a likely outcome for a hypothesis test if a treatment has a very small effect?
- AA type I error.
- BA type II error.
- CCorrectly reject the null hypothesis.
- DCorrectly fail to reject the null hypothesis.
8A research report summarizes the results of the hypothesis test by stating, “z = 2.13, p < .05.” Which of the following is a correct interpretation of this report?
- AThe null hypothesis was rejected and the probability of a Type I error is less than .05.
- BThe null hypothesis was rejected and the probability of a Type II error is less than .05.
- CThe null hypothesis was not rejected and the probability of a Type I error is less than .05.
- DThe null hypothesis was not rejected and the probability of a Type II error is less than .05.
9The null hypothesis was not rejected and the probability of a Type II error is less than .05.
- AThe observations must be independent.
- BThe value for μ must be the same after treatment as it was before treatment.
- CThe value for σ must be the same after treatment as it was before treatment.
- DThe sample must be obtained by random sampling.
10A sample of n = 16 individuals is selected from a population with µ = 80 and σ = 5, and a treatment is administered to the sample. If the treatment really does have an effect, then what would be the effect of increasing the standard deviation to σ = 25?
- AIncrease the chances that the sample will produce an extreme z-score and increase the likelihood that you will conclude that a treatment effect exists.
- BIncrease the chances that the sample will produce an extreme z-score and increase the likelihood that you will conclude that a treatment effect does not exist.
- CIncrease the chances that the sample will produce a z-score near zero and increase the likelihood that you will conclude that a treatment effect exists.
- DIncrease the chances that the sample will produce a z-score near zero and increase the likelihood that you will conclude that a treatment effect does not exist.
11A researcher is predicting that a treatment will increase scores. If this treatment is evaluated using a directional hypothesis test, then the critical region for the test ______.
- AWould be entirely in the right-hand tail of the distribution.
- BWould be entirely in the left-hand tail of the distribution.
- CWould be divided equally between the two tails of the distribution.
- DCannot answer without knowing the value of the alpha level.
12A sample is selected from a population with a mean of µ = 45 and a treatment is administered to the sample. If the treatment is expected to produce a decrease in the scores, then what would be the null hypothesis for a directional hypothesis test?
- Aµ ≥ 45
- Bµ ≤ 45
- CM ≤ 45
- DM ≥ 45
13A researcher expects a treatment to produce an increase in the population mean. The treatment is evaluated using a one-tailed hypothesis test, and the test produces z = –1.85. Based on this result, what is the correct statistical decision?
- AThe researcher should reject the null hypothesis with α = .05 but not with α = .01.
- BThe researcher should reject the null hypothesis with either α = .05 or α = .01.
- CThe researcher should fail to reject H0 with either α = .05 or α = .01.
- DCannot answer without additional information.
14Which of the following is most likely to reject the null hypothesis even if the treatment effect is very small?
- AA small sample and a small value for σ.
- BA small sample and a large value for σ.
- CA large sample and a small value for σ.
- DA large sample and a large value for σ.
15A treatment is administered to a sample selected from a population with a mean of µ = 80 and a standard deviation of σ = 10. After treatment, the sample mean is M = 85. Based on this information, the effect size as measured by Cohen’s d is _____.
- Ad = 5.00
- Bd = 2.00
- Cd = 0.50
- DImpossible to calculate without more information.
16If other factors are held constant, then how does the size of the standard deviation affect the likelihood of rejecting the null hypothesis and the value for Cohen’s d?
- AA larger standard deviation increases the likelihood of rejecting the null hypothesis and increases the value of Cohen’s d.
- BA larger standard deviation increases the likelihood of rejecting the null hypothesis but decreases the value of Cohen’s d.
- CA larger standard deviation decreases the likelihood of rejecting the null hypothesis but increases the value of Cohen’s d.
- DA larger standard deviation decreases the likelihood of rejecting the null hypothesis and decreases the value of Cohen’s d.
17Which of the following defines the power of a hypothesis test?
- AThe probability of rejecting a true null hypothesis.
- BThe probability of supporting true null hypothesis.
- CThe probability of rejecting a false null hypothesis.
- DThe probability of supporting a false null hypothesis.
18How does increasing the sample size influence the likelihood of rejecting the null hypothesis and the power of the hypothesis test?
- AThe likelihood of rejecting H0 and the power of the test both increase.
- BThe likelihood of rejecting H0 and the power of the test both decrease.
- CThe likelihood of rejecting H0 increases but the power of the test is unchanged.
- DThe likelihood of rejecting H0 decreases but the power of the test is unchanged.
19How does an increase in the value of σ influence the likelihood of rejecting the null hypothesis and the power of the hypothesis test?
- AThe likelihood of rejecting H0 and the power of the test both increase.
- BThe likelihood of rejecting H0 and the power of the test both decrease.
- CThe likelihood of rejecting H0 increases but the power of the test is unchanged.
- DThe likelihood of rejecting H0 decreases but the power of the test is unchanged.
Informações
- Descrição
- Year 1 Statistics I Quiz sobre Chapter 8, criado por Eloise Brisson em 29-08-2022.
- Autor
- Eloise Brisson
- Idioma
- English
- Visualizações
- 0
- Etiquetas
- Avaliação
- Ainda sem avaliações Avalie este quiz