Definition: A scatter plot is a graph of ordered pairs that shows the relationship between two numerical variables, revealing any pattern, trend, or outliers.
What is a scatter plot?
Each dot represents one observation with two measurements, one on each axis. Together, the dots show how the variables relate.
What patterns can you see?
- Positive association: as x increases, y tends to increase.
- Negative association: as x increases, y tends to decrease.
- No association: dots scatter with no clear trend.
The pattern can be linear or curved. Clusters and outliers also stand out.
What does an example show?
Mathbot records study hours and quiz scores: (1, 58), (2, 64), (3, 71), (4, 77), (5, 84). The dots climb steadily, a strong positive linear association. Each extra hour adds about 6.5 points.
How do you describe it?
Mention direction, strength, shape, and unusual points. A tight band means strong association, a loose cloud means weak.
What is a common mistake?
Claiming one variable causes the other. Ice cream sales and sunburns rise together, but ice cream does not cause sunburn. Hot weather drives both.