Power series linear regression using

MULTIPLE LINEAR REGRESSION USING A POWER SERIES... 

Amount Transformation. Step 2. The amount transformation was performed in a way similar to that of response by use of a power series but for a different reason. In this case linearity was desired in order to use a simple linear regression model. This transformation therefore required a test for satisfactory conformity. One can use a variety of criteria including the correlation coefficient or visual examination of the plot of rgsiduals verses amount. We chose the F test for lack of fit,... 

Although the linear model is the model most commonly encountered in analytical science, not all relationships between a pair of variables can be adequately described by linear regression. A calibration curve does not have to approximate a straight line to be of practical value. The use of higher-order equations to model the association between dependent and independent variables may be more appropriate. The most popular function to model non-linear data and include curvature in the graph is to fit a power-series polynomial of the form... 

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