to correlate / to be correlated / a correlation
If two things correlate (or: are correlated), it means that there’s a statistical connection between them. So, if the correlation is positive, it means when one thing goes up, the other goes up too. So, for instance, you might find that there’s a positive correlation between self-confidence and success at university. If the correlation is negative, it means that when one thing goes up, the other thing goes down. So, perhaps you’ll find a negative correlation between the amount of time spent watching TV and success at university. The most common statistical calculations used to show correlation are Pearson’s rho and Spearman’s rho (you’ll learn about these when you study research methods). But you always have to be careful not to confuse correlation with cause and effect. Just because, for instance, there’s a correlation between self-confidence and success at university, this doesn’t mean self-confidence causes success. It could be that success causes people to be confident or that both self-confidence and success have a common cause – for instance, family background.
The study found that the two sets of scores were positively correlated.