Question 1

To convert a frequency distribution to a relative frequency distribution, divide each class frequency by the number of classes.

Accepted Answer

To convert a frequency distribution to a relative frequency distribution, divide each class frequency by the total number of data points, not the number of classes.

Question 2

When data is collected using a qualitative, nominal variable, what is true about a frequency distribution that summarizes the data?
A) The upper and lower class limits must be calculated.
B) A pie chart can be used to summarize the data.
C) The number of classes is equal to the number of variable's values plus 2.
D) The "5 to the k rule" can be applieD.

Accepted Answer

Since qualitative, nominal variables are categorical data with no inherent order, the best way to summarize the data is to use a pie chart. Frequency distributions are more commonly used for quantitative data. The upper and lower class limits are not calculated for nominal variables, and the number of classes is equal to the number of variable's values. The "5 to the k rule" is also not applicable in this case.

Question 3

When data is collected using a quantitative, ratio variable, what is true about a frequency distribution that summarizes the data?
A) Upper and lower class limits must be calculated.
B) A pie chart can be used to summarize the data.
C) The number of classes is equal to the number of variable's values.
D) The "5 to the k rule" can be applieD.

Accepted Answer

When data is collected using a quantitative, ratio variable, upper and lower class limits must be calculated in order to create an accurate frequency distribution.

Question 4

A pie chart is similar to a relative frequency distribution.

Accepted Answer

Both a pie chart and a relative frequency distribution show the proportions of different categories within a data set. A pie chart displays this information visually using slices of a circle, while a relative frequency distribution presents it in a table format.

Question 5

To convert a frequency distribution to a relative frequency distribution, divide each class frequency by the sum of the class frequencies.

Accepted Answer

To obtain relative frequencies, we need to divide the class frequency by the total frequency, which is the sum of all the class frequencies.

Question 6

A cumulative frequency distribution is used when we want to determine how many observations lie above or below certain values.

Accepted Answer

A cumulative frequency distribution shows the cumulative frequency of data values that fall below a certain value. This can be used to determine how many observations lie above or below certain values.

Question 7

When data is collected using a qualitative, nominal variable (in other words, male or female), what is true about a frequency distribution that summarizes the data?
A) The upper and lower class limits must be calculated.
B) Class midpoints can be computed.
C) The number of classes corresponds to the number of a variable's values.
D) The "2 to the k rule" can be applieD.

Accepted Answer

When data is collected using a qualitative, nominal variable, such as gender (male or female), the frequency distribution can be created by grouping the data into categories that correspond to the variable's values (male or female). Therefore, the number of classes in the frequency distribution corresponds to the number of values of the variable. The upper and lower class limits are not relevant since there is no numerical data to assign to them, and class midpoints cannot be computed. The "2 to the k rule" is also not applicable for this type of data.

Question 8

The midpoint of a class, which is also called a class mark, is halfway between the lower and upper limits.

Accepted Answer

The statement is true. The midpoint or class mark is calculated by adding the lower and upper limits of a class interval and dividing by 2.

Question 9

Monthly commissions of first-year insurance brokers are $1,270, $1,310, $1,680, $1,380, $1,410, $1,570, $1,180 and $1,420. These figures are referred to as a(n) __________.
A) Histogram
B) Raw data
C) Frequency distribution
D) Frequency polygon

Accepted Answer

Raw data is the unorganized data that has not been processed or summarized. In this case, the monthly commissions of first-year insurance brokers are the raw data.

Question 10

A pie chart shows the relative frequency in each class.

Accepted Answer

A pie chart is a graphical representation that shows the relative frequency or proportion of each class as a sector or slice of a circle.

Question 11

A frequency distribution for qualitative data has class limits.

Accepted Answer

Qualitative data is categorized into classes or categories, not numerical intervals, so it does not have class limits.

Question 12

In a bar chart, the heights of the bars represent the frequencies in each class.

Accepted Answer

The heights of the bars in a bar chart represent the frequencies or values for each category or class being represented.

Question 13

To summarize the gender of students attending a college, the number of classes in a frequency distribution depends on the number of students.

Accepted Answer

The number of classes in a frequency distribution for categorical data like gender is determined by the number of categories (e.g., male, female, non-binary), not the number of students.

Question 14

A small sample of computer operators shows monthly incomes of $1,950, $1,775, $2,060, $1,840, $1,795, $1,890, $1,925, and $1,810. What are these ungrouped numbers called?
A) Histogram
B) Class limits
C) Class frequencies
D) Raw data

Accepted Answer

Raw data refers to unorganized, ungrouped data that has not been put into any categories or classes.

Question 15

A class interval, or class width, can be determined by subtracting the lower limit of a class from the lower limit of the next higher class.

Accepted Answer

This is the correct formula for determining the class interval or class width of a frequency distribution.

Question 16

A frequency distribution groups data into classes showing the number of observations in each class.

Accepted Answer

A frequency distribution is a way of grouping numerical data into classes or intervals and displaying the count or percentage of observations that fall into each class. Therefore, the statement is true.

Question 17

To construct a pie chart, relative class frequencies are used to graph the "slices" of the pie.

Accepted Answer

Pie charts represent relative class frequencies as the angles of the "slices" of the pie, with each slice representing a different class/category.

Question 18

A frequency polygon is a very useful graphic technique when comparing two or more distributions.

Accepted Answer

A frequency polygon is a type of graph that displays the shape of a data distribution by connecting data points representing the frequencies of the values in the dataset, making it easier to compare two or more distributions.

Question 19

In frequency distributions, classes are mutually exclusive if each individual, object, or measurement is included in only one category.

Accepted Answer

Classes in frequency distributions are mutually exclusive if each individual, object or measurement is included in only one category.

Question 20

In a bar chart, the x-axis is labeled with the values of a qualitative variable.

Accepted Answer

A bar chart is used to display the distribution of a categorical (qualitative) variable, with the x-axis representing the categories and the y-axis representing the frequency or count of each category.

Quiz 2: Describing Data: Frequency Tables, Frequency Distributions, and Graphic Presentation