00:01
A researcher finds that as her subjects increase the number of hours they spent exercising, their weight decreased.
00:07
Is this a positive correlation, b a negative, c a zero, or d, a causal? so i'll start by saying it's not causal.
00:19
We have no reason to believe there's a causation.
00:21
I mean, we can see a correlation, but we'd have to research further to find a causation.
00:26
And we can't say there's zero because it clearly says that as exercise increases, weight decreases.
00:35
So is it negative or positive? well, let's plot it out.
00:39
So as the, we'll put exercise on the bottom here, and we'll put weight along here.
00:47
So low exercise is high weight, and then as exercise increases, weight decreases, like so...