1. STATISTICS: TYPES OF VARIABLES Claire 12B

2. 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.

3. 1) Nominal Variables  A variable that divides the sample into different groups.

4. Examples  Gender: male and female  Marital status: unmarried and married

5. 2) Ordinal Variables  An ordinal variable ranks or divides a sequence in order, but the intervals may not be the same.

6. Examples  Best student cities ranking  Best universities ranking  Customer satisfaction rate (very unsatisfactory, unsatisfactory, moderate, satisfactory, very satisfactory)

7. 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.

8. 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.

9. Examples  Number of countries in the world  Number of girls in a class  Number of cousins you have  Number of books you have

10. 2) Continuous Variables  A continuous variable represents numerical data as accurately as possible.

11. Examples Price of books  Age of students in a class  Temperature

12. 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.

13. 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?

14. 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.