# Effect of Outliers on Fit of Growth Models

Effect of Outliers on Fit of Growth Models

The choice of a population’s growth model is frequently influenced by its fit to experimental growth curves, which in turn can be discernibly affected by the data scatter and presence of outliers. This Demonstration allows visualization and quantification of these effects by generating smooth or randomly scattered growth data with the shifted logistic equation and fitting them with the Gompertz and stretched exponential (Weibullian) models by nonlinear regression. One to three outliers can be added manually at chosen locations and their effect on the fitted growth curve’s shape and fit parameters assessed.