Revisar envio do teste_ Atividade - Statistics 4 _

Prévia do material em texto

13/06/2020 Revisar envio do teste: Atividade - Statistics 4 – ...
https://anhembi.blackboard.com/webapps/assessment/review/review.jsp?attempt_id=_35215752_1&course_id=_469700_1&content_id=_959495… 1/4
 
Revisar envio do teste: Atividade - Statistics 4
Estatística Avaliação e Certificado Acesse a atividade e o Certificado de Statistics 4
Revisar envio do teste: Atividade - Statistics 4 
Usuário MANOEL AMBROSIO MAGESTE DOS SANTOS
Curso Estatística
Teste Atividade - Statistics 4
Iniciado 13/06/20 15:48
Enviado 13/06/20 17:46
Status Completada
Resultado da tentativa 7 em 10 pontos 
Tempo decorrido 1 hora, 58 minutos
Resultados exibidos Respostas enviadas, Respostas corretas, Comentários
Pergunta 1
Resposta Selecionada: 
Resposta Correta: 
Feedback
da
resposta:
Skill: Determine the likelihood of making type I and type II errors, and explain how to reduce them, in
context.
"multiple choice" question: select the correct answer.
A pharmaceutical company would like to asses the effectiveness of a new pain reliever and test the
following:H0: The drug is not effectiveHa: The drug is effectiveThe company runs an experiment and the
data do not provide enough evidence to conclude that the drug is effective. What type of error is possible in
this situation?
 Type II
 Type II
This is correct. It is possible that even though based on the data the researchers cannot
conclude that the drug is effective, in reality the drug actually is effective. In other words, there
is a risk that the researchers fail to reject the null hypothesis by mistake. This is type II error.
Pergunta 2
Skill: Perform inference for the linear relationship between two quantitative variables
"multiple choice" question: select the correct answer. The following output is available:
Based on the output, which of the following is the appropriate conclusion?
Minha Área
1 em 1 pontos
1 em 1 pontos
MANOEL AMBROSIO MAGESTE DOS SANTOS
http://portal.anhembi.br/
https://anhembi.blackboard.com/webapps/blackboard/execute/courseMain?course_id=_469700_1
https://anhembi.blackboard.com/webapps/blackboard/content/listContent.jsp?course_id=_469700_1&content_id=_9594944_1&mode=reset
https://anhembi.blackboard.com/webapps/blackboard/content/listContent.jsp?course_id=_469700_1&content_id=_9594954_1&mode=reset
https://anhembi.blackboard.com/webapps/portal/execute/tabs/tabAction?tab_tab_group_id=_358_1
https://anhembi.blackboard.com/webapps/login/?action=logout
13/06/2020 Revisar envio do teste: Atividade - Statistics 4 – ...
https://anhembi.blackboard.com/webapps/assessment/review/review.jsp?attempt_id=_35215752_1&course_id=_469700_1&content_id=_959495… 2/4
Resposta Selecionada: 
Resposta Correta: 
Feedback da resposta:
The data provide strong evidence that IQ and DI are linearly related.
The data provide strong evidence that IQ and DI are linearly related.
This is correct.
Pergunta 3
Resposta Selecionada: 
Resposta Correta: 
Feedback da
resposta:
Skill: Carry out the chi-square test for the independence of two categorical variables and draw meaningful
conclusions.
"multiple choice" question: select the correct answer. 
The Chi-square test statistic is calculated using the observed and expected counts of the cells of the two-
way table. Suppose that for one particular cell:
Observed count = 35
Expected count =25
What is the contribution of this cell to the Chi-square test statistic? 
4
4
This is correct. The contribution to the Chi-square test statistic of this cell is:(Observed
count − Expected Count)2 Expected Count=(35−25)225=10025=4.
Pergunta 4
Resposta Selecionada: 
Resposta Correta: 
Feedback da
resposta:
The Medical College Admission Test (MCAT) is an examination for prospective medical students.Suppose
that based on data collected from a random sample of 100 MCAT takers, the 95% confidence interval for μ,
the mean MCAT score, was calculated to be (497, 503).
Skills:
Calculate interpret the confidence interval for the population mean , and recognize the effect of level of
confidence and sample size on the precision of the interval estimation. Calculate interpret the confidence
interval for the population proportion p, and recognize the effect of level of confidence and sample size on
the precision of the interval estimation.
"multiple choice" question: select the correct answer.
What is the margin of error of this confidence interval?
3
3
This is correct. The margin of error is half the width of the confidence interval which in
this case is (503-497)/2=3.
Pergunta 5
Resposta Selecionada: 
Resposta Correta: 
Skill: Determine the likelihood of making type I and type II errors, and explain how to reduce them, in
context.
"multiple choice" question: select the correct answer. What can be done in order to reduce the risk of Type I
error?
Increase the sample size
Choose a smaller significance level (for example, 0.01 instead of 0.05)
1 em 1 pontos
1 em 1 pontos
0 em 1 pontos
13/06/2020 Revisar envio do teste: Atividade - Statistics 4 – ...
https://anhembi.blackboard.com/webapps/assessment/review/review.jsp?attempt_id=_35215752_1&course_id=_469700_1&content_id=_959495… 3/4
Pergunta 6
Resposta Selecionada: 
Resposta Correta: 
Skill: Determine the likelihood of making type I and type II errors, and explain how to reduce them, in
context.
"multiple choice" question: select the correct answer. What can be done in order to reduce the risk of Type
II error?
Choose a smaller significance level (for example, 0.01 instead of 0.05).
Increase the sample size.
Pergunta 7
Resposta
Selecionada:
Resposta Correta: 
Skill: Carry out the hypothesis test for the population proportion and draw conclusions in context. "multiple
choice" question: select the correct answer.
Recall that in order to assess whether the new Intro Stats course format reduces the non-completion rate, a
random sample of 300 California community college students who took the course in the new format was
chosen and it was found that 66 of them (22%) did not complete the course.Which of the following would
have provided stronger evidence that the new course format reduces the non-completion? In other words,
which of the following would have resulted in a smaller p-value for this test?
A random sample of 500 students was chosen and 110 of them (22%) did not
complete the course.
Both (B) and (C) are correct
Pergunta 8
Resposta Selecionada: 
Resposta Correta: 
Feedback da
resposta:
Skills: Carry out the hypothesis test for the population proportion and draw conclusions in context
Carry out the hypothesis test for the population mean and draw conclusions in context
"multiple choice" question: select the correct answer. Suppose that we would like to test:H0:μ=10Ha:μ≠10at
the 5% significance level. In addition, suppose that based on the collected data the 95% confidence interval
for μ is (8.4, 11.1). Which of the following is correct?
Since 10 falls inside the confidence interval we can reject H0.
Since 10 falls inside the confidence interval we can reject H0.
This is correct. Since 10 falls inside the confidence interval, it is, based on the data, a
plausible value for μ. We therefore cannot reject H0.
Pergunta 9
Resposta
Selecionada:
Skill: Carry out the hypothesis test for the population proportion and draw conclusions in context. "multiple
choice" question: select the correct answer.
In 2015 60% of all U.S. adults supported same-sex marriage. We would like to test whether the proportion
of all U.S. adults who support same-sex marriage has increased since then. In a recent poll, 20 U.S. adults
were randomly chosen and 13 of them (65%) supported same-sex marriage.Can we safely use the z-test
for p in this case?
Which of the following is correct?
0 em 1 pontos
0 em 1 pontos
1 em 1 pontos
1 em 1 pontos
13/06/2020 Revisar envio do teste: Atividade - Statistics 4 – ...
https://anhembi.blackboard.com/webapps/assessment/review/review.jsp?attempt_id=_35215752_1&course_id=_469700_1&content_id=_959495… 4/4
Sábado,13 de Junho de 2020 17h48min02s BRT
Resposta Correta:
Feedback da
resposta:
It is not safe to use the z-test for p in this case since 20*(1-.60) is not large
enough.
It is not safe to use the z-test for p in this case since 20*(1-.60) is not large
enough.
This is correct. It is not safe to use the z-test for p in this case since n(1-
p0)=20(1-.60)=8 is not at least 10.
Pergunta 10
Resposta Selecionada: 
Resposta Correta: 
Feedback da resposta:
Skill: Carry out the hypothesis test for the population mean and draw conclusions in context
"Fill in the blank" question: select the correct answer.
Consider the following two scenarios involving hypothesis testing the population mean, and complete the
sentences that follow.
I. The mean IQ score of adults is known to be 100. In order to test whether the mean IQ of lawyers is higher
than 100, a random sample of 10 lawyers was chosen and their IQ measured and recorded. It was found
that for the 10 sampled lawyers the average IQ score was 101.4 with a standard deviation of 14.5. It is
known that IQ scores follow a normal distribution.
II. The mean IQ score of adults is known to be 100. In order to test whether the mean IQ of lawyers is
higher than 100, a random sample of 10 lawyers was chosen and their IQ measured and recorded. It was
found that for the 10 sampled lawyers the average IQ score was 101.4. It is known that IQ scores follow a
normal distribution with standard deviation of 15.
Complete the following sentences: In scenario I, the , and therefore the should be used.In scenario II, the ,
and therefore the should be used.
standard deviation is calculated from the sample
standard deviation is calculated from the sample
This is correct.
← OK
1 em 1 pontos
javascript:launch('/webapps/gradebook/do/student/viewAttempts?course_id=_469700_1&method=list&nolaunch_after_review=true');