Deck 9: Comparing Means Between Two Groups

Question 1

A one-sample t-test and a paired-sample t-tests have what in common?

A) two groups being tested
B) measurements taken at two points in time
C) a dichotomous dependent variable
D) a continuous dependent variable

Answer 1

D

Question 2

One assumption of the t-test, that is often violated, is the assumption that the data is ___________.

A) normally distributed
B) collected by the researcher
C) not missing any responses
D) linear

Answer 2

A

Question 3

The t-test grew out of the work of whom?

A) William Student
B) William Gosset
C) William Guinness
D) A group of students working at the Guinness Brewery

Answer 3

B

Question 4

Professors at a university are interested in the students' level of research skills at the beginning of a course and at the end of that course. What type of research design describes this situation?

A) snapshot design
B) repeated measures design
C) paired-samples design
D) matched-subject design

Question 5

Jim's null hypothesis is that Rockwood Fire Department's response time is ___________ the 5 minute national standard.

A) greater than
B) less than
C) equal to
D) not equal to

Question 6

An appropriate test to use with a repeated measures design is the ________________.

A) one-sample t-test
B) independent samples t-test
C) paired-sample t-test
D) dependent-sample t-test

Question 7

Connor is trying to determine if he is meeting the company standard of loading 60 pallets of grain per hour onto company trucks. What test should he perform to determine if he is significantly higher or lower than the company standard?

A) one-sample t-test
B) independent samples t-test
C) paired sample t-test
D) Levene's test

Question 8

The independent variable in an independent sample t-test must be what type of variable?

A) dichotomous
B) continuous
C) ordinal
D) interval

Question 9

With _________ cases the t-test is said to be fairly robust against the violation of normal distribution.

A) less than 15
B) less than 40
C) 40 or more
D) 100 or more

Question 10

Which of the following pairings would be used in a matched-subjects design?

A) males and females
B) people who ate lunch and people who did not eat lunch
C) a husband and wife pair
D) The same group at times 1 and 2

Question 11

Leo is performing a t-test to examine if there is a significant difference in cultural competency between a group of people who went through a diversity training and a group who did not complete the training. What is the dependent variable in this example?

A) number of trainings attended
B) level of cultural competency
C) the control group
D) there is no dependent variable in this example

Question 12

Jim runs a paired sample t-test to compare emergency vehicle response time in 2009 to emergency vehicle response time in 2010 and obtains a p-value of .04. What does this mean?

A) There is no significant difference between 2009 and 2010 response times
B) There is a significant difference between 2009 and 2010 response times
C) The response time in 2010 was significantly lower than the response time in 2009
D) The response time in 2010 was significantly higher than the response time in 2009

Question 13

Jamie is studying the perception of parental roles by surveying pairs of brothers and sisters. What type of research design describes this situation?

A) matched-subject design
B) independent t-test
C) paired-sample design
D) repeated measures design

Question 14

The assumption in the independent sample t-test that the variances for the two populations are equal is also known as the assumption of __________.

A) heterogeneity of variance
B) homogeneity of variance
C) equality of variation
D) normal distribution

Question 15

An appropriate test to use with a matched-subjects design is the ________________.

A) one-sample t-test
B) independent samples t-test
C) paired-sample t-test
D) dependent-sample t-test

Question 16

If you are comparing the mean scores of two groups with no overlapping members, you would use a(n) _______________.

A) descriptive statistics analysis
B) one-sample t-test
C) paired sample t-test
D) independent samples t-test

Question 17

If you want to compare the level of knowledge about sexual harassment laws of the same group of people before and after training, the test you would use is a __________.

A) before and after t-test
B) one-sample t-test
C) independent samples t-test
D) dependent sample t-test

Question 18

A test which compares the mean of one group to a set value is called a ______________.

A) descriptive statistic test
B) independent samples t-test
C) dependent sample t-test
D) one-sample t-test

Question 19

One of the assumptions of the t-test is that the variable from which the mean is calculated is a _______________ variable.

A) categorical
B) dichotomous
C) continuous
D) ordinal

Question 20

Brian is interested in the level of satisfaction of new clients who visit the city employment department before and after he changes the model of service delivery. What test would you use in this situation?

A) descriptive statistics
B) one-sample t-test
C) paired sample t-test
D) independent samples t-test

Question 21

It is possible to violate the assumption of normal distribution and still have a robust result.

Question 22

A p-value of less than .05 on the Levene's Test indicates that the group means are significantly different from each other.

Question 23

The one-sample t-test has a dichotomous independent variable.

Question 24

The independent samples t-test and paired-sample t-test both have ________________.

A) a continuous dependent variable
B) a continuous independent variable
C) a dichotomous dependent variable
D) repeated measures design

Question 25

For Jim's Case and Emily's case, identify the number and type of independent and dependent variables.

Question 26

Do you think Jim's research is in alignment up to this point? Why or why not?

Question 27

Identify the three types of t-tests. For each type of t-test, identify a research question that could be tested using that t-test.

Question 28

The purpose of both the independent samples t-test and paired sample t-test is to analyze how closely related the two groups are to one another.

Question 29

When Jim compared the response times between 2010 and 2011, this is an example of a repeated measures design.

Question 30

A t-test which examines the difference between a group of males and a group of females on a biology test has two independent variables.

Question 31

A paired-sample t-test can be used to examine the difference between males and females perception of marital satisfaction when the sample is made up of married couples.

Question 32

The __________ is used to determine if the population variances of two groups are equal.

A) independent samples t-test
B) Levene's test
C) paired sample t-test
D) one-sample t-test

Question 33

A t-test assumes a continuous independent variable.

Question 34

If the Levene's test is not significant, you must report the adjusted t-value.

Question 35

When comparing means, you can look at the _______________ to determine if the difference is statistically significant.

A) p-value
B) descriptive statistics
C) mean of each group
D) median of each group
True/False

Question 36

The t-test is used to examine the __________________ between groups.

A) relationship
B) overlap
C) difference
D) correlation

Question 37

The one-sample t-test assumes that the groups have equal variances.

Question 38

An independent samples t-test or paired sample t-test is used when you are comparing the means of _________ group(s).

A) one
B) two
C) three
D) any number of