Looking at example seven, I've given you guys another scatter plot of education and salary in thousands of dollars. For starters, would you guys say this trend is linear or nonlinear? Which one would you guys say is this trend: linear or nonlinear? Yeah, it looks pretty linear to me. And so again, when you have linear trends, that is the reason why we can use the correlation coefficient. All right, linear trends are the only time you can use an r correlation coefficient. Now again, when it comes to looking at the correlation coefficient, r, you are looking at both the sign of r. So you're asking, is 0.777 positive or negative? As well as looking at how close r is to either positive or negative one. So I want to emphasize when you are interpreting the correlation coefficient, you need to look at it twice. And that's why I wrote it down in two different colors. So in this case, the first thing you need to do is identify if r is positive or negative. Which one do we have here, is it positive or negative? Yeah, this r value is positive. So because of that, we are going to have a positive association. You look at the r value and you determine, is it close to either 1, 0, or positive one? Which one do we have here? 0.777, is that close to negative 1, zero, or positive one? Yeah, it's close to positive one. And so what type of association are we going to have here? Is it going to be strong or is it going to be weak? It's strong, it's a strong association. Perfect. Again, I wanted to teach you guys how to look at the sign of r to determine the positiveness or negativeness of the trend. I wanted you to look at the value of r to determine the strength of the trend. But here's the thing, after you have interpreted the value of r, you don't want to just write positive association or strong association. What you want to do is you want to emphasize the correlation coefficient in the context of the problem. All right, meaning you're going to want to actually include the variables that this association is representing. So what do I mean by that? Well, we would say that there is a positive and strong association between what? Well, my horizontal variable, education years of education, and my vertical variable, salary in thousands of dollars per year. When it comes to interpreting r, it's not just enough to say positive, negative, weak, strong. You need to still give the context. You still need to include in this association what two things are you looking at. So make sure to include context, AKA both variables, right? That's really the point of this sentence here. I'm trying to emphasize we are including context when you write out the full sentence. And then in addition to that, remembering that the years of education is the horizontal variable, meaning we want to see how does this horizontal variable lead to that vertical variable. And so I want you guys to read example C, read example C, and only one sentence is correct. Correct, and it's because of one word. I want you guys to read through both sentences. Which one do you think is the correct sentence? First or second? Yeah, yeah, you guys tell me. What do you think is the key word here that made this first sentence correct? Yeah, it's the word "tend". It's the word "tend". I want you guys to remember that this positive association, meaning more years of experience tends to have higher salaries. The word "tend" is so important because when it comes to these strong correlations, I mean to emphasize that they are not causations. They are not causations. And that's the reason why it's so important to use the word "tend" because "tend" is emphasizing, I see it generally, more years of education leads to higher salaries, but it's not a causation. The thing I want to emphasize here is that we do not have a causation. Having more education does not automatically give you more money. 100% absolutely. How do I know this? Because me and my friend both went to UC Davis. We both got science degrees. He stopped at his bachelor's degree in computer science, working for Cisco. He makes three times as much as me. I got a master's degree. I got two years more of education. I have an additional degree above him. But because I opted to go into teaching, I make like half of his salary. And so there isn't a one-to-one "more education, more you get paid" scenario. It's just a general upward trending.