1. The number that occurs most frequently in a data set is
a. mean
b. median
c. mode
d. harmonic
2. What type of graphic presents data in terms of frequencies per category?
a. Pie chart
b. Line graph
c. Bimodal distribution
d. Histogram
3. When you are dealing with a normal distribution of scores, which measure of central tendency is preferred?
a. Mean
b. Median
c. Mode
d. All of the above, as they will be the same in this distribution
4. The _______ is a single number that represents the total amount of variability in a distribution.
a. standard deviation
b. variance
c. range
d. mean
5. Correlation coefficients represent
a. The degree of relationship between two variables
b. causality between two relationships
c. whether the independent variable had an effect
d. all of the above
6. Which of the following would probably be negatively correlated?
a. The number of days in class and exam grade
b. The height and weight of college students
c. The number of difficult classes taken and semester GPA
d. Overall college GPA and graduate school GPA
7. A perfect positive correlation occurs when
a. an increase of 1 unit is always accompanied by a proportional increase in the other variable
b. there is no relationship between the two variables
c. an increase of 1 unit is always accompanied by a lesser increase in the other variable
d. an increase of 1 unit is always accompanied by a greater increase in the other variable
8. You are reading an article that says age and number of sick days taken per year has a correlation of -0.72. How would you interpret this correlation?
a. A weak, positive correlation
b. A weak, negative correlation
c. A strong, negative correlation
d. A strong, positive correlation
9. If a data set has the following data pointsâ5,6,7,6,7âyou would expect the standard deviation to be
a. a small number, because the numbers do not vary much from the mean of 6.2
b. a large number, because the numbers do not vary much from the mean of 6.2
c. a large number, because the numbers vary a great deal from the mean of 6.2
d. a small number, because the numbers vary a great deal from the mean of 6.2
10. Descriptive statistics are
a. procedures using the experimental method
b. procedures used to analyze data after an experiment
c. procedures used to summarize a set of data
d. all of the above
11. The standard deviation is the square root of the
a. variance
b. mean
c. range
d. sum of the raw scores
