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Introduction to correlation

Introduction to correlation - PostgreSQL Tutorial

From the course: SQL for Statistics Essential Training

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Introduction to correlation

- [Instructor] Correlation is a measure of how the values of two variables change with respect to each other. For example, we can see in this screen that, as the value of units sold increases, the value of revenue increases as well. Correlation considers how two columns change value together. When the variables increase in value together, they are considered correlated. We just saw an example of correlated or positively correlated with revenues increasing as the number of units sold increase. When one value increases and another decreases, then we call those values negatively correlated. An example of negative correlation is the relation between a discount on the sale price of a unit and the revenue generated from the sale of that unit.

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