 Statistics and Excel. Correlation and Regression. Got data? Let's get stuck into it with statistics and Excel. First question. What is correlation? Correlation measures the strength and direction of the linear relationship between two variables. And whenever we think about correlation, we have to keep in mind the common phrase of correlation does not necessarily mean causation. However, when a phrase becomes as common as this one, correlation does not equal causation. It often loses some meaning. People often saying it as a kind of mantra without really thinking deeply about what the mantra originally meant. So we'll come back to this phrase here and possibly multiple times through the presentation. But first, a quick recap of what we have done in prior sections and prior sections. We have just tried to describe different data sets using both math math.