statistics: types of variables claire 12b. qualitative variables a qualitative variable is a...
TRANSCRIPT
STATISTICS: TYPES OF VARIABLES
Claire 12B
Qualitative Variables
A qualitative variable is a categorical variable that represents different groups and relates to non-numerical data like hair colors and favorite books.
1) Nominal Variables
A variable that divides the sample into different groups.
Examples
Gender: male and female
Marital status: unmarried and married
2) Ordinal Variables
An ordinal variable ranks or divides a sequence in order, but the intervals may not be the same.
Examples
Best student cities ranking
Best universities ranking
Customer satisfaction rate (very unsatisfactory, unsatisfactory, moderate, satisfactory, very satisfactory)
Quantitative Variables
A quantitative variable relates to numerical data and is measured on a quantitative scale. Examples include a country’s population and a book’s price.
1) Discrete Variables
A discrete variable can only take integers as its value, and its number of values is finite (limited). Examples include AP scoring scale (1-5) and SAT scoring scale (200-800). An AP score cannot be 4.5, and an SAT score cannot be 2345.4.
Examples
Number of countries in the world
Number of girls in a class
Number of cousins you have
Number of books you have
2) Continuous Variables
A continuous variable represents numerical data as accurately as possible.
Examples
Price of books Age of students in
a class Temperature
Quiz
1) If I divide a group of people into different sections based on their hair colors, is the variable qualitative? Quantitative?
2) If I rank the world universities, what kind of variable is it? Explain.
3) Explain four sub-groups of two types of variables.
Quiz 2
4) If I divide the test scores based on gender, what type of variable is it? (State specifically)
5) Can I use continuous variables to indicate the number of pencils I have? Why or why not?
Answers
1) Qualitative 2) Ordinal because it ranks the
universities with different intervals. 3) Qualitative (nominal, ordinal)
Quantitative (discrete, continuous) 4) Nominal (Qualitative) 5) No because only discrete variable can
be used to indicate countable numbers (integers) with limited value.