Abstract
The use of linear regression to obtain the parameter estimates for a nonlinear model could lead to imprecise results. This comment is to point out the problem of linearization in the parameter estimation for a nonlinear model. In Oke (2008), the reliability of ultimate BOD (L_{0}) and BOD removal rate (k) were first calculated using the Weibull plotting position formula and then the L_{0}reliability and kreliability data were fit to a nonlinear systemreliability model. Model parameters were estimated based on a linearized model and the linear regression. In this comment, we examine and compare the results of parameter estimation from the linear and nonlinear regressions. According to the residual plots, the nonlinear regression gives better estimates of the parameters than the linear one.
Original language  English 

Pages (fromto)  13651367 
Number of pages  3 
Journal  Environmental Engineering Science 
Volume  26 
Issue number  8 
DOIs 

State  Published  1 Aug 2009 
Keywords
 Probability plot; linearization; nonlinear regression; residual plot