INDEX multiple linear regression

It should be noted that the above definition of Xj is different from the one often found in linear regression books. There X is defined for the simple or multiple linear regression model and it contains all the measurements. In our case, index i explicitly denotes the i"1 measurement and we do not group our measurements. Matrix X, represents the values of the independent variables from the i,h experiment. 

A simple two-component relationship for hERG blocking potency was proposed by Aptula and Cronin [37], A set of 150 descriptors were calculated for 19 structurally diverse hERG blockers from the literature. The calculated variables included physicochemical parameters, topological indexes, and quantum chemical descriptors. Multiple linear regression was used to derive a relationship between hERG blocking potency and two descriptors, -log D and Dmax (the maximum diameter of molecules) ... 

Hall and Kier reexamined this BCF data set using the response surface optimization technique as reported for a neurotoxicity data set.In this approach the nonlinear parabolic form is extended to a general two-variable parabolic form. The analysis can be performed using ordinary multiple linear regression programs or an extended form of the analysis can be performed using SAS. For the 20 compounds investigated by Sabljic, Hall and Stewart " used the sum and difference of the zero order chi indexes, "x "id defined as follows ... 

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