Judging associations

In this activity, students can use the reference information on the strength of association of scatter plots found in Is There an Association?

The scatter plots below show data about 136 students at age 18 for three variables: leg length (cm), weight (kg) and strength (kg).

Which plot do you think represents which pairs of variables?

  1. leg length and weight
  2. leg length and strength
  3. strength and weight
Three plots with clusters of values rising from left to right showing moderate spread, less spread and greater spread.

The scatter plots.

Give reasons for your choices.

You can download the file Judging Associations: Answers.

There are other activities available in difficulties with informal inference.

Curriculum links

Year 10: Use scatter plots to investigate and comment on relationships between two numerical variables