Overfitting can make you miss overarching trends by inviting you to model too much detail, resulting in some bizarre predictions. Here is a graph of twelve data points for population values in the United States since the beginning of the last century. The overall trend is best described by a quadratic equation, but if we use an equation of degree 11 to match the point exactly and extend this equation into the future, it takes a dramatic lurch downward, absurdly predicting complete annihilation of the US population in the middle of October 2028. (Or perhaps the mathematics knows something we
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