Trend Lines and Regression Lines

Regression: Fitting Functions to Data shows us how to create trend lines, or regression lines. These lines are very popular in graphs, helping to visualize the trend of the data.

> ...we see how to obtain a linear or exponential model from two data points: we only need to find the equation of the line or exponential curve passing through them. However, it often happens that we have many data points that don't quite all lie on one line or exponential curve. The problem then is to find the line, exponential curve, quadratic curve, or what have you coming closest to passing through all of the points. the relationship between price and demand, or cost. In this interactive module, we discuss how we can come up with such a model.

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