Understanding Scatter Plots
A scatter plot turns two columns of numbers into a picture, revealing at a glance whether two things move together, apart, or not at all.
The Idea
A scatter plot graphs bivariate data, two variables, as points on an x-y plane, making patterns and relationships between them visible.
A scatter plot makes a relationship between two variables something you can see, not just calculate.
How to Read One
Direction
An upward trend means a positive relationship; a downward trend means a negative one.
Strength
Tightly clustered points indicate a strong relationship; scattered ones indicate a weak one.
Form
The pattern can be linear, curved, or random with no relationship at all.
Outliers
Points far from the pattern may be errors or unusual cases worth investigating.
Atomic Ideas From This Page
A scatter plot makes a relationship between two variables visible.Plotting paired values as points turns numbers into a pattern you can see.
Direction shows whether variables move together or apart.An upward trend is a positive relationship; a downward one is negative.
The tightness of the cluster shows the strength of a relationship.Points near a line indicate a strong link; scattered points a weak one.
The form of a relationship can be linear, curved, or absent.The shape of the points tells you what kind of relationship exists, if any.
Outliers are points that break the pattern.They may signal data errors or genuinely unusual cases worth a closer look.
Two columns of numbers, one revealing picture.