Thus the present version of the package drc provides a user-friendly interface for specification of model assumptions about the dose-response relationship (including a flexible suite of built-in model functions) as well as for summarizing fitted models and making inference on derived parameters. Meanwhile it has become a flexible and versatile package for dose-response analyses in general. Subsequently the package has been modified and extended substantially, mostly in response to inquiries and questions from the user community. Originally, drc was developed to provide nonlinear model fitting for specialized analyses that were routinely carried out in weed science. There also exist a number of other R packages related to dose-response analysis: DoseFinding, drfit, grofit, MCPMod, and nlstools.
One such specialized sub system for analysis of dose-response data is provided through the add-on package drc. The programming infrastructure has fuelled the development of highly sophisticated sub systems for more or less specialized statistical analyses within a number of scientific areas (e.g., the Bionconductor suite of packages: ). Over the last 20 years the open-source environment R has developed into an extremely powerful statistical computing environment. We are aware of the commercial software GraphPad ( ) as well as a few standalone programmes (e.g., and ). Availability of specialized commercial statistical software for dose-response analysis is limited.
However, except for a few special cases the analysis easily becomes cumbersome as relevant, but non-standard output requires manual programming. Dose-response analysis can be carried out using multi-purpose commercial statistical software.