Statistics - 2

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Pergunta 1
1 em 1 pontos
	
	
	
	The Dean of Students at a large university wants to know what proportion of a freshmen students are happy with the academic advising the university provides. The Dean obtains a list of all freshman students who visited the Academic Advising Center during the past month and selects and collects data from a random sample of 100 students from that list.
Skill: Identify the sampling method and its potential limitations.
"multiple choice" question: select the correct answer. In this case the population of interest is:
	
	
	
	
		Resposta Selecionada:
	 
All the Freshman students at the university
	Resposta Correta:
	 
All the Freshman students at the university
	
	
	
Pergunta 2
1 em 1 pontos
	
	
	
	The Dean of Students at a large university wants to know what proportion of a freshmen students are happy with the academic advising the university provides. The Dean obtains a list of all freshman students who visited the Academic Advising Center during the past month and selects and collects data from a random sample of 100 students from that list.
Skill: Identify the sampling method and its potential limitations.
"multiple choice" question: select the correct answer. In this case, all the Freshman students who are happy with the advising that the university provides is the:
	
	
	
	
		Resposta Selecionada:
	 
None of the above
	Resposta Correta:
	 
None of the above
	
	
	
Pergunta 3
1 em 1 pontos
	
	
	
	The Dean of Students at a large university wants to know what proportion of a freshmen students are happy with the academic advising the university provides. The Dean obtains a list of all freshman students who visited the Academic Advising Center during the past month and selects and collects data from a random sample of 100 students from that list.
Skill: Identify the sampling method and its potential limitations.
"multiple choice" question: select the correct answer. The HR department chooses a random sample of 5 employees from each of the 120 bank’s branches and collects data from the 600 selected employees. The sampling method in this case is:
	
	
	
	
		Resposta Selecionada:
	 
Stratified sampling
	Resposta Correta:
	 
Stratified sampling
	
	
	
Pergunta 4
1 em 1 pontos
	
	
	
	Unit: Producing Data
Module: Designing Studies
A weight loss program provides three follow-up methods to choose from for individuals who went through the program and reached their desired weight: monthly in-person meeting, monthly on-line meeting, and monthly newsletter by mail. In order to assess the effectiveness of the three follow-up methods, the program selects a random sample of 291 individuals who went through the program and reached their desired weight and classifies them according to the follow-up method that they sign-up for. A year later the study finds that 30% of those who chose to sign up for the in-person follow-up method regained more than 5 pounds, 50% of those who chose to sign-up for the online method regained more than 5 pounds and 70% of those who chose to sign-up for the newsletter method regained more than 5 pounds.
Skill: Identify the design and other features of a study
"multiple choice" question: select the correct answer.
Which of the following is the correct design of this study?
	
	
	
	
		Resposta Selecionada:
	 
An observational study
	Resposta Correta:
	 
An observational study
	Feedback da resposta:
	This is correct.
	
	
	
Pergunta 5
0 em 1 pontos
	
	
	
	The Dean of Students at a large university wants to know what proportion of a freshmen students are happy with the academic advising the university provides. The Dean obtains a list of all freshman students who visited the Academic Advising Center during the past month and selects and collects data from a random sample of 100 students from that list.
Skill: Identify the sampling method and its potential limitations.
"multiple choice" question: select the correct answer. In this case, the sampling frame is:
	
	
	
	
		Resposta Selecionada:
	 
All the Freshman students at the university
	Resposta Correta:
	 
All the Freshman students who visited the Academic Advising Center during the past month
	
	
	
Pergunta 6
1 em 1 pontos
	
	
	
	Skill: Determine how the features of a survey impacts the quality of the collected data
"multiple choice" question: select the correct answer. Which of the following would be the best question to include in a poll in order to assess the opinions of U.S. adults about legalizing marijuana?
	
	
	
	
		Resposta Selecionada:
	 
Which of the following best describes your view about legalizing the use of marijuana?
Strongly favor legalizing the use of marijuana
Favor legalizing the use of marijuana
Oppose legalizing the use of marijuana
Strongly oppose legalizing the use of marijuana
Not sure
	Resposta Correta:
	 
Which of the following best describes your view about legalizing the use of marijuana?
Strongly favor legalizing the use of marijuana
Favor legalizing the use of marijuana
Oppose legalizing the use of marijuana
Strongly oppose legalizing the use of marijuana
Not sure
	
	
	
Pergunta 7
1 em 1 pontos
	
	
	
	Skills: Identify the design and other features of a study
Understand how the design of a study impacts the type of conclusions that can be drawn
"multiple choice" question: select the correct answer.
A study explored the relationship between drinking diet soda and the risk of stroke. The researchers followed a group of individuals who are ‘diet soda drinkers’ and a group of individuals who are not diet soda drinkers and found a higher rate of stroke among those who are diet soda drinkers. After the researchers collected more data, they discovered that the weight of the individuals was significantly higher, on average, in the diet soda drinkers group.
Which of the following is true?
	
	
	
	
		Resposta Selecionada:
	 
Weight is a lurking variable
	Resposta Correta:
	 
Weight is a lurking variable
	
	
	
Pergunta 8
1 em 1 pontos
	
	
	
	Unit: Producing Data
Module: Designing Studies
A weight loss program provides three follow-up methods to choose from for individuals who went through the program and reached their desired weight: monthly in-person meeting, monthly on-line meeting, and monthly newsletter by mail. In order to assess the effectiveness of the three follow-up methods, the program selects a random sample of 291 individuals who went through the program and reached their desired weight and classifies them according to the follow-up method that they sign-up for. A year later the study finds that 30% of those who chose to sign up for the in-person follow-up method regained more than 5 pounds, 50% of those who chose to sign-up for the online method regained more than 5 pounds and 70% of those who chose to sign-up for the newsletter method regained more than 5 pounds.
'Smart drinks' are beverages containing vitamins and amino acids, which are marketed as helpful to mental performance. To investigate the claimed effect of a particular 'smart drink' for the general adult population, a health researcher obtains 250 adults who volunteer for a beverage-and-memory study. Each of the subjects is then randomly assigned to get one beverage from among two possible: Either the 'smart drink' or else a ‘fake smart drink’ – a drink that looks and tastes the same as the 'smart drink', but does not contain any vitamins or amino acids). The subjects did not know which of the two beverages they were assigned to drink. After drinking, each subject is told to memorize a list of words; the subjects are then tested on how many words they can correctly recall. The number of correctly-recalled words is recorded for each subject.
Skill: Understand how the design of a study impacts the type of conclusions that can be drawn"multiple choice" question: select the correct answer. If the number of words recalled is really significantly higher on average in the 'smart drink' group, can we reasonably conclude that the improved recall of those in the 'smart drink' group was actually caused by the smart drink?
	
	
	
	
		Resposta Selecionada:
	 
Yes, since the individuals were randomly assigned to drink either the ‘smart drink’ or the ‘fake smart drink’.
	Resposta Correta:
	 
Yes, since the individuals were randomly assigned to drink either the ‘smart drink’ or the ‘fake smart drink’.
	
	
	
Pergunta 9
1 em 1 pontos
	
	
	
	Skill: Identify the sampling method and its potential limitations.
"multiple choice" question: select the correct answer. The HR department collects data from the 578 of bank’s employees who happen to call the HR department during the past two months. The sampling method in this case is:
	
	
	
	
		Resposta Selecionada:
	 
Convenience Sampling
	Resposta Correta:
	 
Convenience Sampling
	
	
	
Pergunta 10
1 em 1 pontos
	
	
	
	Skill: Identify the sampling method and its potential limitations.
"multiple choice" question: select the correct answer. At random, the HR Department selects 20 of the 120 bank’s branches, and from each of the selected branches selects a random sample of 15 male and 15 female employees. The sampling method in this case is:
	
	
	
	
		Resposta Selecionada:
	 
Multistage sampling
	Resposta Correta:
	 
Multistage sampling
	Feedback da resposta:
	This is correct. This is an example of multistage sampling (first stage: cluster sampling, second stage: stratified sampling).