How to compare the fitting of function?
Thank you. The problem was the implementation of the goodness-of-fit in R (any method, really). regards
On Tue, Jul 7, 2020 at 1:31 PM Ivan Krylov <krylov.r00t at gmail.com> wrote:
On Tue, 7 Jul 2020 08:57:28 +0200 Luigi Marongiu <marongiu.luigi at gmail.com> wrote:
I would say that the function Gompertz is better than the function Holling type III; how can I give a number to this hunch?
There are many different goodness-of-fit measures; typically, regression problems are solved by minimising the sums of squared residuals, so you can just take a look at those (sum((y.predicted - y.reference)^2)). Root-mean-square-error [*] is another widely used metric. When comparing different methods, one should be aware of multiple comparisons problem [**] and potential for overfitting [***]. All this and more is discussed in books on statistics and regression, such as Regression Modeling Strategies by Frank E. Harrell, Jr. [doi:10.1007/978-3-319-19425-7]. For more advice on statistics, consider dedicated communities such as <https://stats.stackexchange.com/>, since statistics advice is considered off-topic here in R-help. -- Best regards, Ivan [*] https://en.wikipedia.org/wiki/RMSE [**] https://en.wikipedia.org/wiki/Multiple_testing [***] https://en.wikipedia.org/wiki/Overfitting
Best regards, Luigi