Polynomial Interpolation: Extrapolation

Extrapolation

Extrapolation is the process of predicting a value that lies outside the range of the known base points. Extrapolation using polynomials should be treated with extreme care. For example, the Runge function described above predicts, when , the value of . Had we used extrapolation using the fitted polynomial, the predicted value would have been which does not really follow the trend of the interpolated points!