Quiz
5
Question
1 of 25
1.0
Points
The
__________ is a hypothesis-testing procedure used when a sample mean is being
compared to a known population mean and the population variance is unknown.
A.ANOVA
B.t test for a single sample
C.t test for multiple samples
D.Z test
Question
2 of 25
1.0
Points
In
the formula for estimating the population variance from the scores in a sample,
the sum of squared deviations is divided by:
A.the number of participants in the sample
B.the number of participants in the sample
minus one
C.the number of participants in the population
D.the number of participants in the population
minus one
Question
3 of 25
1.0
Points
Which
of the following is TRUE about t distributions?
A.There are exactly 10 categories of t distributions.
B.For any given sample size, there are between
two and N-1 appropriate t distributions.
C.The larger the sample size, the more a t
distribution resembles a normal curve.
D.t distributions are generally bimodal.
Question
4 of 25
1.0
Points
The
variance of a sample is said to be “biased” because it consistently __________
the actual variance of the population.
A.overestimates
B.underestimates
C.enlarges
D.divides
Question
5 of 25
1.0
Points
A
local newspaper reports that young women in your town (i.e., a known
population) sleep an average of only 5 hours per night. However, you think that
women in your town who are enrolled at your college sleep more than that. You
randomly select 200 women from your college and ask them to accurately record
their hours of sleep. You find that they sleep an average of 7 hours per night.
What test would you use to determine whether this mean difference is
statistically meaningful?
A.ANOVA
B.t test for dependent means
C.t test for a single sample
D.regression
Question
6 of 25
1.0
Points
What
is the main difference between Z score and t score?
A.t scores are used when the study requires a
one-tailed test
B.t scores are used when the population
variance is unknown
C.t scores are used whenever the sample size
is greater than 30
D.t scores are only used when inferences are
made about other samples
Question
7 of 25
1.0
Points
The
shape of a t distribution:
A.is typically bimodal
B.is typically rectangular
C.will vary according to the mean of the
population you used to estimate sample variance
D.will vary according to the degrees of
freedom in the sample you used to estimate population variance
Question
8 of 25
1.0
Points
The
t score is your sample’s mean minus the __________ divided by the __________.
A.sample size; variance of the distribution of
means
B.sample size minus 1; standard deviation of
the distribution of means
C.population mean; standard deviation of the
distribution of means
D.population median; variance of the distribution
of means
Question
9 of 25
1.0
Points
Difference
scores are usually used with:
A.a t test for a single sample
B.a t test for dependent means
C.a t test for independent means
D.all of the above
Question
10 of 25
1.0
Points
Other
names for the t test for dependent means include all of the following EXCEPT:
A.paired-sample t test
B.t test for matched samples
C.t test for matched pairs
D.independent-sample t test
Question
11 of 25
1.0
Points
The
difference between a person’s score on one testing and the same person’s score
on another testing:
A.test score
B.deleted score
C.distance score
D.difference score
Question
12 of 25
1.0
Points
Suppose
a researcher conducted a t test for dependent means using scores from pairs of
research participants (i.e., mothers and sons). The researcher considered each
pair as if it were one person and calculated a difference score for each pair.
In this example, the t test could also be called a:
A.t test for matched pairs
B.t test for unmatched pairs
C.t test for mixed pairs
D.t test for independent pairs
Question
13 of 25
1.0
Points
Which
of the following is an assumption or requirement within the logic and
mathematics of the t test?
A.A sample of more than 50 people
B.A normal population
C.A normal sample
D.A mean change score that is greater than 10
Question
14 of 25
1.0
Points
The
estimated effect size for a study using a t test for dependent means is the
mean of the difference scores divided by the:
A.difference scores
B.estimated variance of the sample of
difference scores
C.estimated standard deviation of the
population of difference scores
D.estimated mean of the population of
difference scores
Question
15 of 25
1.0
Points
What
is considered a medium effect size for a t test for dependent means?
A..20
B..30
C..50
D..80
Question
16 of 25
1.0
Points
Which
of the following is an assumption for the t test for dependent means?
A.The population variance is known.
B.The population mean is greater than the sample
mean.
C.The population follows a normal
distribution.
D.The sample follows a normal distribution.
Question
17 of 25
1.0
Points
For
a research study that utilized a t test for dependent means, an effect size of .98
would be considered:
A.small
B.medium
C.large
D.very large
Question
18 of 25
1.0
Points
Power
for a t test for dependent means can be determined using:
A.a power software package
B.an Internet power calculator
C.a power table
D.any of the above
Question
19 of 25
1.0
Points
When
utilizing t tests, __________ would be considered an adequate amount of power.
A.40%
B.50%
C.65%
D.80%
Question
20 of 25
1.0
Points
What
is often a limitation of research using a repeated-measure design?
A.low power
B.lack of control group
C.low standard deviation of difference scores
D.all of the above
Question
21 of 25
1.0
Points
What
type of research design would be expected to yield the highest amount of power
(assuming studies with the same sample size)?
A.A study using a Z test
B.A study using a t test
C.A study using a single-sample design
D.A study using a repeated-measures design
Question
22 of 25
1.0
Points
Approximately
how many research participants would be required for 80% power for a study
using the t test for dependent means (assume a one-tailed hypothesis with an
expected medium effect size of .50):
A.12
B.26
C.33
D.196
Question
23 of 25
1.0
Points
Approximately
how many research participants would be required for 80% power for a study
using the t test for dependent means (assume a two-tailed hypothesis with an
expected small effect size of .20):
A.156
B.196
C.26
D.33
Question
24 of 25
1.0
Points
What
is the approximate power for a study using the t test for dependent means with
an expected large effect size, one-tailed and N = 50? Answer: D
A.40
B.77
C.88
D.nearly 1
Question
25 of 25
1.0
Points
If
not otherwise indicated, one should assume that researchers utilized a
__________ test. Answer: B
A.one-tailed
B.two-tailed
C.whole sample
D.partial sample
