Scatterplots and Correlations - Problem 2 3,507 views
It’s really easy to determine a correlation between two variables if you are given a graph but you can still do it even if you don’t have a graph by using logic. Let’s look at this what kind of correlation would you expect between age and hearing ability?
Well you guys know that in general, this isn’t true for every person but in general as people get older their hearing gets worse. So as one variable gets larger right, as your age gets larger your hearing ability gets smaller it decreases. That’s what we call a negative correlation. As one gets larger the other one get smaller.
Let’s look at this one what kind of correlation would you expect between a person’s GPA and height? Well GPA and height aren’t really related. You might be able to urge that the taller you are the better you can see over people or maybe tall people maybe you're on the basketball team and so they don’t spend enough time whatever doing their how work we don’t know. In general this would be a no correlation.
When you're doing these problems try not to get caught up in the details like maybe somebody this or maybe somebody that and maybe somebody went to the concert when they were 6 and they lost it, whatever. Don’t try to get caught up in those little specifics, just go with in general, general trends.
Correlations describe a general association between two variables.