Video Transcript
Suppose variable 𝑥 is the number of hours you work, and variable 𝑦 is your salary. You suspect that the more hours you work, the higher your salary is. Does this follow a positive correlation, a negative correlation, or no correlation?
So to help us understand this question, what I’ve done is drawn a little sketch of some axes. So along the 𝑥-axis, we have hours worked because this is our 𝑥-variable. And with the 𝑦-axis, we have salary because this is our 𝑦-variable. Well, what it says in the question is that you suspect that the more hours you work, the higher your salary is. So therefore, we can see that with some points we plotted here, we can see that as the hours increase, the salary increases.
So before we decide which type of correlation is this, let’s remind ourselves of our correlation types. So we’ve got positive correlation, which we can see usually with a trend that goes up to the right, so from the bottom left up to the right. No correlation would be where the data is not correlated at all, and there’s no definite pattern. And with negative correlation, we’d see it going down to the right, so from the top left down to the right, and that would show us negative correlation.
So if we take a look back at our scenario, we can see that it goes up to the right. And that’s because our 𝑦-variable, salary, increases as the 𝑥-variable, hours worked, increases. So therefore, we can say that the scenario follows a positive correlation.
