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Concept explainers
Categorical or quantitative? Identify each of the following variables as categorical or quantitative.
- a. Number of children in family
- b. Amount of time in football game before first points scored
- c. College major (English, history, chemistry,…)
- d. Type of music (rock, jazz, classical, folk, other)
a.
![Check Mark](/static/check-mark.png)
Identify whether the variable is categorical or quantitative variable.
Answer to Problem 90CP
The variable number of children in family is quantitative variable.
Explanation of Solution
The given variable is that “number of children in family”.
Categorical variables and quantitative variables:
The variables are classified as categorical and quantitative variable. Quantitative variables are those variables that take numerical values while categorical variables do not take numerical values. Therefore, categorical variables are those in which observations belong to one set of categories and quantitative are those variables in which observation are numerical values.
The number of children in family can take values 0, 1, 2… etc. That is, the variable “number of pets in family” can take numerical values. Therefore, number of children in family is quantitative variable.
b.
![Check Mark](/static/check-mark.png)
Identify whether the variable is categorical or quantitative variable.
Answer to Problem 90CP
The variable amount of time in football game before first point is quantitative variable.
Explanation of Solution
The given variable is that “amount of time in football game before first point”.
The amount of time in football game before first point can take numerical values. Therefore, amount of time in football game before first point is quantitative variable.
c.
![Check Mark](/static/check-mark.png)
Identify whether the variable is categorical or quantitative variable.
Answer to Problem 90CP
The variable college major is categorical variable.
Explanation of Solution
The given variable is that “college major”.
The variable college major includes name of the subjects such as English, history, chemistry, etc. That is, the variable cannot take numerical values these are different subjects. Therefore, the variable college major is categorical variable.
d.
![Check Mark](/static/check-mark.png)
Identify whether the variable is categorical or quantitative variable.
Answer to Problem 90CP
The variable type of music is categorical variable.
Explanation of Solution
The given variable is that “type of music”.
The type of music is rock, jazz, classical, folk, and others. That is, the variable types of music do not take numerical values. Therefore, the variable type of music is categorical variable.
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Chapter 2 Solutions
Statistics: The Art and Science of Learning from Data (4th Edition)
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