Cogito
Probability and Statistics · Chapter 1 · Lesson 1
Types of Data and Their Displays
Choose the graph the data deserves.
12 problems · about 20 minutes · TEKS P.S.1.A, S-ID.A.1
What this lesson teaches
The student distinguishes categorical from quantitative data and selects an appropriate display.
- Categorical data sorts; quantitative data measures.
- If averaging the values is meaningless, the data is categorical.
- Describe a distribution by shape, centre, spread and outliers.
Warm Up
Straightforward practice. Get the method working first.
5 problemsHair colour is which kind of data? 1 categorical, 2 quantitative.
Answer 1
Why Categorical.
Why do histogram bars touch while bar chart bars do not?
Answer Histogram values run continuously; bar chart categories are separate.
Why The gap reflects genuinely separate categories.
Height in centimetres. 1 categorical, 2 quantitative.
Answer 2
Why An amount.
Favourite sport. 1 or 2?
Answer 1
Why A group.
Number of siblings. 1 or 2?
Answer 2
Why A count you could average.
Build It Up
The same ideas with more to keep track of.
3 problemsPostcode. 1 or 2?
Answer 1
Why A numeric label.
Do histogram bars touch? 1 for yes, 0 for no.
Answer 1
Why The numbers run continuously.
How many features describe a distribution: shape, centre, spread and outliers?
Answer 4
Why Count them.
Stretch Yourself
Mixed problems. Work out what kind of question it is before you start.
4 problemsSort each variable by its type.
Answer Categorical: Blood type, Shoe brand · Quantitative: Weight in kilograms, Test score
Why Ask whether averaging the values would mean anything.
Temperature in degrees. 1 or 2?
Answer 2
Why A measured amount.
The Survey: Eye colour is which kind of data? Enter 1 for categorical, 2 for quantitative.
Answer 1
Why Categorical.
The Jerseys: Jersey numbers on a team are which kind? 1 categorical, 2 quantitative.
Answer 1
Why Categorical, despite looking numeric.