Chapter 2

A cumulative frequency distribution is

• a. a tabular summary of a set of data showing the relative frequency.

• b. a tabular summary of a set of data showing sums of frequencies.

• c. a tabular summary of a set of data showing the frequency of items in each of several nonoverlapping classes.

• d. a graphical device for presenting categorical data.

A researcher is gathering data from four geographical areas designated: South = 1; North = 2; East = 3; West = 4. The designated geographical regions represent

• a. categorical data.

• b. quantitative data.

• c. crosstabular data.

• d. either categorical or quantitative data.

In quality control applications, bar charts are used to identify the most important causes of problems. When the bars are arranged in descending order of height from left to right with the most frequently occurring cause appearing first, the bar chart is called a

• a. Cause-and-effect diagram.

• b. Ogive.

• c. Pareto diagram.

• d. Stacked bar chart.

A graphical device for depicting categorical data that have been summarized in a frequency distribution, relative frequency distribution, or percent frequency distribution is a

• a. histogram.

• b. stem-and-leaf display.

• c. dot plot.

• d. bar chart.

Which of the following is least useful in making comparisons or showing the relationships of two variables?

• a. Stacked bar chart

• b. Stem-and-leaf display

• c. Crosstabulation

• d. Scatter diagram

A tabular summary of a set of data showing the fraction of the total number of items in several classes is a _____ distribution.

• a. frequency

• b. relative frequency

• c. cumulative relative frequency

• d. cumulative frequency

The numbers of hours worked (per week) by 400 statistics students are shown below. The relative frequency of students working 0 - 9 hours per week is

• .05

• .20

• .25

• .50

In a crosstabulation

• both variables must be categorical.

• both variables must be quantitative.

• one variable must be categorical and the other must be quantitative.

• either or both variables can be categorical or quantitative.

The most common graphical presentation of quantitative data is a

• histogram.

• bar chart.

• dot plot.

• pie chart.

For stem-and-leaf displays where the leaf unit is not stated, the leaf unit is assumed to equal

• 0.

• -1.

• 1.

• 10.