Chapter 2: Describing Data: Frequency Tables, Frequency Distributions,
Suppose that the miles per gallon for 80 cars is summarized in a frequency distribution. Below is a part of the distribution. What would the relative frequency be for the class "20 up to 24?" MPG Frequency 16 up to 20 10 20 up to 24 16
0.20
A frequency distribution table shows the number of observations for each class interval of data. How is this data plotted as a frequency polygon?
Frequency is plotted on the vertical axis and the class midpoint is plotted on the horizontal axis.
Which of the following would useful to represent as a frequency table?
Gender of students in a business statistics course. Majors of students in a business statistics course. State of residence of students in a business statistics course.
Which of the following is an advantage of a cumulative frequency polygon over a histogram or frequency polygon?
It can show the total number of observations less than a particular class' upper limit.
Which one of the following is not a characteristic of a frequency distribution?
It summarizes qualitative data.
Which of the following best describes a frequency table?
No observation can fit into more than one class. They can be used for qualitative data.
Which of the following are characteristics of frequency distributions?
Organize raw data Use classes and frequencies to organize data It provides the tally for each class.
Which of the following are characteristics of bar charts?
Plotted rectangles should be the same width. Bar charts are used for qualitative data. There should be gaps between bars.
Which of the following can be observed from a histogram?
The concentration of the data. The approximate number of observations. The spread of the data. The shape of the distribution.
Which of the following features is not part of a histogram?
The frequency of occurrence of a nominal variable.
What information is shown on the horizontal axis of a bar chart?
The qualitative class labels.
Which of the following operations is true regarding relative frequency distributions?
The relative frequency is found by dividing the class frequencies by the total number of observations.
Which of the following is a feature of a relative frequency distribution?
The sum of the relative frequencies must be one (assuming no rounding errors).
Which of the following are characteristics of frequency tables?
They can be used for qualitative data. No observation can fit into more than one class.
A frequency polygon shows the shape of a distribution and is similar to:
a histogram
In a frequency polygon the points are plotted at the intersection of the class frequencies and the:
class midpoints
The value shown on the vertical axis of a cumulative frequency polygon for a particular class is found by:
counting the number of observations less than the upper limit of the class
A relative frequency distribution shows:
the fraction or percentage of observations in each class interval
