Lesson 12 : Bivariate
Analysis II – Testing Relations
Each question has only one best answer. Circle clearly the letter of the best answer. If
you make a mistake, cross out the circle, and write the letter in capitals next
to the question. If a question has both a capital letter and is circled, the
letter will be considered to be the answer.
1.
Tammy
wants to know whether state levels of Internet usage covary with state education
levels. She represents all 50 states as dots on an usage-by-education graph.
Then she draws a line through the dots that minimizes the distances from each
state’s position in the plot to the line. What is this line called?
a.
The
least squares line
b.
The
regression line
c.
The
best-fitting line
d.
b
and c
e.
a,
b and c
2.
The
formula for the regresssion line is y = a +
bx. What statement(s) is(are) true about the variable a?
a.
a is a constant.
b.
a is
the dependent variable
c.
a represents
the point where the regression line crosses the
y axis.
d.
a is the independent variable
e.
a
and c.
3.
Saskia
correlated respondents’ ages with their incomes and got a Pearson’s r of 0.30 What percentage of the variance did she explain in her
data?
a.
6%
b.
9%
c.
15%
d.
30%
e.
60%
4.
What
is the PRE measure that tells you how much better you could do if you predicted
the separate means for chunks of your data than if you predicted the mean for
all your data?
a.
eta
b.
eta-squared
c.
Pearson’s
r.
d.
r
2
e.
gamma.
5.
Under
what conditions is it acceptable to treat ordinal-level variables as if they
were interval?
a.
When
there are large sample sizes
b.
When
there are fewer than 5 ordinal categories
c.
When
there are at least 11 ordinal categories
d.
When
there are 5 or more ordinal categories
e.
Whenever
you want.
6.
What
is another word for extreme values?
a.
Weights
b.
Outliers
c.
Gemeinschaft
d.
Gesellschaft
e.
Bonferroni
correction.
7.
What
is the best thing to do with outliers?
a.
Eliminate
them
b.
Keep
them in
c.
Report
the results of your analysis with and without them
d.
Divide
them by the sample size
e.
Throw
out the highest and lowest scores.
8.
What
does the Bonferroni correction do?
a.
It
corrects for the probability of getting a correlation significant at some known
level by chance alone.
b.
It
increases the size of the p value
you can accept to reject your null hypothesis.
c.
It
tells you how big a sample you need
d.
It
tells you how many times to repeat an experiment
e.
None
of the above.
9.
What
do you need to calculate statistical power?
a.
The
minimum size of the difference between two outcomes that you will accept as a
real difference.
b.
The
sample size
c.
The
variance
d.
a
and b
e.
a,
b and c.
10.
John
is doing some exploratory research. After collecting data on 20 different
variables, he creates a correlation matrix and looks for relationships that are
statistically significant. What is John doing?
a.
Conducting
an outlier analysis
b.
Shotgunning
c.
Conducting
a confirmatory analysis
d.
Conducting
a power analysis
e.
Calculating
the Bonferroni correction.
11.
T
F To test for the possibility that one mean is higher than another, you need to
do a one-tailed t-test.
a.
True
b.
False
12.
T
F Analysis of variance requires that the Ns from each group must be equal.
a.
True
b.
False
13.
T
F Systematic patterns in data are always linear.
a.
True
b.
False
14.
T
F A lambda of zero means that there is clearly no association between two
variables.
a.
True
b.
False
15.
T
F Sample size affects the value of chi-square
a.
True
b.
False
16.
T
F Cramer’s V and phi are measures of association among two
nominal variables and are based on chi-square.
a.
True
b.
False
17.
T
F Values for gamma range from 0 to 1 .
a.
True
b.
False
18.
T
F it is possible to test whether a value of a Pearson’s r is the result of sampling error or reflects a real covariation in
the larger population.
a.
True
b.
False.