correlated

Everyday

1. (adjective) When two things are correlated, they tend to change together: when one goes up, the other usually goes up (or down) too: «Height and shoe size are correlated». tree →
2. (verb, past) Compared or connected two things to see how they match: «The scientist correlated the temperature with ice-cream sales». tree →

In the lessons

In maths and science lessons on data and graphs, pupils learn that points on a scatter graph can show a positive correlation (both rise), a negative correlation (one rises as the other falls) or no correlation. A key lesson is «correlation does not mean causation»: two things changing together does not prove one causes the other. Phrases: «positively correlated», «negatively correlated», «correlated with», «strongly correlated».

Examples

• Hours of practice and test scores were correlated. tree →
• Ice-cream sales and sunny days are positively correlated. tree →
• Temperature and the number of people wearing coats are negatively correlated. tree →
• The researchers correlated the children's sleep with their marks. tree →
• Just because two things are correlated does not mean one causes the other. tree →
• Our scatter graph showed that arm span and height are strongly correlated. tree →

Note

The verb is «correlate» (correlates, correlated, correlating); the noun is «correlation». Spelled with double r. Trap: ice-cream sales and sunburn are correlated, but ice cream does not cause sunburn; both are caused by sunny weather. In maths, «positively correlated» means both numbers grow together; «negatively correlated» means one grows as the other shrinks.