Chapter 7 iClicker Questions
1. The z test is:
a) another way to calculate the mean.
b) the simplest of the hypothesis tests.
c) a non-parametric test.
d) used only with data that is composed of negative numbers.
2. If Laura received a z score of 1 for her performance on a standardized
math test, approximately what percentage of scores is below her score?
a) 34.13%
b) -34.13%
c) 84.13%
d) -84.13%
3. From the example above, what percentage of scores are between Laura’s
z score and the mean?
a) 34.13%
b) -34.13%
c) -84.13%
d) 84.13%
4. A z score has a known mean and standard deviation. What are they?
a) Mean = 50, SD=2.0
b) Mean = 0, SD=3
c) Mean = 50, SD= 1
d) Mean = 0, SD = 1
5. Roberta scored in the 85th percentile on a standardized test of reading
ability. What is Roberta’s associated z score?
a) -1.04
b) 2.3
c) 3.1
d) 1.04
6. If we obtain a z score of 2.5, what is our raw score for a given population
mean of 800 and a standard deviation of 100?
a) 1000
b) 1600
c) 900
d) 1050
7. The figure below demonstrates the concept of converting a given
percentile to a raw score for a student who scored in the 63rd percentile.
Thirteen percent corresponds to the associated percentage that results from
subtracting the area below the mean from the 63rd percentile. What is the
associated z score?
a) 50
b) 0.33
c) 13
d) 63
8. What are the three assumptions for hypothesis testing?
a) independent variable is measured on an interval scale, participants are
based on a convenience sample, and the population distribution is
approximately normal
b) extraneous variables are controlled for, random selection, and random
assignment
c) dependent variable is measured on an interval or ratio scale,
participants are randomly selected, and population distribution is
approximately normal
d) variables are all continuous, variables are measured on a ration scale of
measurement, and participants are randomly selected
9. _______________ are inferential statistical analyses based on a set of
assumptions about the population.
a) Standardized tests
b) Non-standardized tests
c) Parametric tests
d) Nonparametric tests
10. All of the following are among the six steps of hypothesis testing
EXCEPT:
a) identifying the populations, comparison distribution, and assumptions.
b) determining the characteristics of the comparison distribution.
c) determining critical values, or cutoffs.
d) randomly selecting participants from the population.
11. When researchers say that a result is statistically significant they mean:
a) the data differ from what we would expect by chance if there were, in
fact, no actual difference.
b) the finding must be important and meaningful.
c) the result is huge.
d) the result is important and meaningful to them, but necessarily to other
researchers.
12. A researcher hypothesizes that there is a significant relationship between
stress and fatigue. Specifically, he hypothesizes that, as stress increases,
fatigue levels will also increase. This example best illustrates what type of
hypothesis test?
a) null hypothesis
b) one-tailed test
c) two-tailed test
d) non-directional test
13. A researcher hypothesizes that there is a significant relationship
between stress and fatigue. Specifically, he hypothesizes that, as stress
increases, fatigue levels will change. This example best illustrates what type
of hypothesis test?
a) null hypothesis
b) one-tailed test
c) two-tailed test
d) uni-directional test
14. All of the following are ways that researchers clean up dirty data
EXCEPT:
a) assign the mode or the men for that variable based on the other
participants’ results.
b) assign the mode or the mean from the participant’s own responses if there
are similar items in the database.
c) assign a random number that is within the range of possible numbers for
that data set.
d) assign a random number that is outside the range of numbers for the
data set so it won’t be confused with the real data.