Chapter 2 Test Statistics

What should not be done when constructing a frequency distribution?

Use a class width with an even number.

What is the range of the data: 4, 7, 3, 16, 5, 22, and 8?

19

If a frequency distribution had class boundaries of 132.5–147.5, what would be the class width?

15

Is a grouped frequency distribution used when the range of the data values is relatively small?

False.

What does the lower class limit represent?

The smallest data value that can be included in the class.

What is the number of values in a specific class of distribution called?

Frequency.

When data are collected in original form, what are they called?

Raw data.

What type of frequency distribution should Greg use for political affiliation?

Categorical.

What is the lower class boundary in the class 13–17?

13.5.

What is the midpoint of the classes 13.5–17.3?

15.4.

Using the class 23–35, what is the upper class boundary?

35.5.

What is obtained by first adding the lower and upper limits and then dividing by 2?

Midpoint.

If the limits for a class were 20–38, what would the boundaries be?

19.5–38.5.

When the range is large, what type of frequency distribution is used?

Grouped.

For the class 16.3–23.8, what is the width?

False.

What are the boundaries of the class 1.87–3.43?

1.879–3.439.

How do you find the class with the least number of data values?

Look at the frequencies and identify the lowest.

What is an ogive graph also called?

Cumulative frequency graph.

What is the cumulative frequency?

The sum of the frequencies accumulated to the upper boundary of a class.

What are the three most commonly used graphs in research?

Histogram, bar graph, and cumulative frequency graph.

What type of graphs display distributions as proportions instead of raw data?

Relative frequency graphs.

Which type of graph uses vertical bars to indicate frequencies?

Histogram.

What is a frequency polygon?

A graph that displays data using lines that connect points plotted for the frequencies at the midpoints.

How does a histogram represent data?

Uses midpoints for x-values and frequencies for y-values.

What do we call data that are less than 28.5 in the provided distribution?

What is it called when data is clustered at one end?

Skewed.

What graph should a weatherman use to record rain data over time?

Time series graph.

What type of graph shows data in a visual way for easier analysis?

Graphs.

What does a time series graph represent?

Data occurring over a specific period.

What sizes do units in a Pareto chart follow?

Decreasing in size.

In an automobile dealer's pie graph, how many degrees do convertibles represent?

80°.

If pepperoni pizza makes up 24/72 of a pie chart, how many degrees represent it?

120°.

Which graph is best to represent classes taken at a school?

Pie graph.

What does it mean to exaggerate a one-dimensional increase in a graph?

Misleading graph.

What does a Pareto chart do with its data?

Arranges data from largest to smallest according to frequencies.

What is a compound time series graph?

When two sets of data are compared on the same graph using two lines.

Is a pie graph suitable to represent inches of rain over two months?

False.

What graph best shows weekly bread sales at a supermarket?

Pie chart.

What graph would represent statistics enrollments over ten years?

Time series.

Is the section depicting families with three children in a pie graph accurate?

True.

If Karen found that 8/24 did homework for three hours, how many degrees is that?

120°.