An education counselor records the number of high school graduates enrolled in
community colleges, four-year colleges, and universities. What scale of measurement is
the type of college?
A) nominal
B) ordinal
C) interval
D) ratio - Answer A
A researcher records the following data: 4, 4, 4, 4, and 3. How would you describe the
variability of these data?
A) It is equal to zero because scores are approximately the same.
B) It is negative because 3 is less than the other scores in the distribution.
C) It is very small (close to 0) because scores are approximately the same.
D) It is very large (much greater than 0) because 3 is an outlier in the data. - Answer C
A researcher reports that "the average shopper in the sample (n = 12) purchased
$65.00 worth of items ( = $65.00) during a busy shopping day." What mistake was
made is this citation?
A) None; this citation is written appropriately.
B) The sample mean is written using the wrong notation.
C) The sample size is written using the wrong notation.
D) both B and C - Answer B
The sample variance is:
A) an unbiased estimator of the population variance
B) associated with n - 1 degrees of freedom
C) computed by dividing SS by df
D) all of the above - Answer D
Regardless of the number of scores in a distribution, the range only includes ___
score(s) in its calculation.
A) one
B) two
C) at most two
D) the average - Answer b
A researcher records 17 scores. What is the median position of these scores?
A) the 9th score in numeric order
B) the average of the 9th and 10th scores in numeric order
C) the average of the 8th and 9th scores in numeric order
D) It's not possible to know this without the raw scores. - Answer A
, A researcher records the following data for the number of dreams recalled during a
night of sleep for 10 college students: 3, 2, 4, 4, 3, 1, 1, 0, 2, and 0. Is the mean equal to
the median in this example?
Yes.
No; the median is larger than the mean.
No; the mean is larger than the median.
There is not enough information to answer this question. - Answer a
A researcher selects a sample of 24 participants and has them complete a survey on
dating preferences. In this example, what are the degrees of freedom for sample
variance and what does this figure represent?
A) df = 24; it represents the number of scores that are free to vary in a sample.
B) df = 23; it represents the number of scores that are free to vary in a sample.
C) df = 23; dividing SS by df makes the sample variance a biased estimator of the
population variance.
D) df = 24; dividing SS by df makes the sample variance an unbiased estimator of the
population variance. - Answer B
Which of the following best describes a dependent variable?
A) the sample variable
B) the measured behavior
C) the manipulated variable
D) the population variable - Answer B
10. The "empirical rule" states that
A) all scores will fall within 3 standard deviations of the mean.
B) at least 68% of scores fall within 1 standard deviation of the mean.
C) at least 95% of scores fall within 2 standard deviation of the mean.
D) both b and c - Answer D
Which of the following will decrease the value of the mean?
A) deleting a score below the mean
B) adding a score below the mean
C) adding a score exactly equal to the mean
D) none of the above - Answer B
12. To construct a pie chart, first distribute the data as
A) cumulative percentages
B) relative percentages
C) cumulative frequencies
D) cumulative relative percentages - Answer B
13. A researcher records the time in seconds it takes a sample of participants to walk
alone through a dark portion of campus. The researcher computes SS = 1,000.
Assuming that a sample of 11 participants was observed in this study, what is the
standard deviation for these data?