Regression Using a Power Series

MULTIPLE LINEAR REGRESSION USING A POWER SERIES 

LINEST can also be used to find the regression coefficients for equations of higher order. It is sometimes convenient, in the absence of a suitable equation, to fit data to a power series. The equation can then be used for data interpolation. Often a power series y = a + hx + cx + dx is sufficient to fit data of moderate curvature. The lowest order polynomial that produces a satisfactory fit should be used if there are N data points, the highest order polynomial that can be used is of order (N -1). 

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