# Johannes Ranke

#### 7 packages on CRAN

Simple functions for plotting linear calibration functions and estimating standard errors for measurements according to the Handbook of Chemometrics and Qualimetrics: Part A by Massart et al. There are also functions estimating the limit of detection (LOD) and limit of quantification (LOQ). The functions work on model objects from - optionally weighted - linear regression (lm) or robust linear regression ('rlm' from the 'MASS' package).

Calculation routines based on the FOCUS Kinetics Report (2006, 2014). Includes a function for conveniently defining differential equation models, model solution based on eigenvalues if possible or using numerical solvers and a choice of the optimisation methods made available by the 'FME' package. If a C compiler (on windows: 'Rtools') is installed, differential equation models are solved using compiled C functions. Please note that no warranty is implied for correctness of results or fitness for a particular purpose.

A somewhat outdated package of basic and easy-to-use functions for fitting dose-response curves to continuous dose-response data, calculating some toxicological parameters and plotting the results. Please consider using the more powerful and actively developed 'drc' package. Functions that are fitted are the cumulative density function of the log-normal distribution ('probit' fit), of the logistic distribution ('logit' fit), of the Weibull distribution ('weibull' fit) and a linear-logistic model ('linlogit' fit), derived from the latter, which is used to describe data showing stimulation at low doses (hormesis). In addition, functions checking, plotting and retrieving dose-response data retrieved from a database accessed via 'odbc' are included. As an alternative to the original fitting methods, the algorithms from the 'drc' package can be used.

Utilities for writing to 'LibreOffice Writer' (see <https://www.libreoffice.org/discover/writer/> for more information) documents using the 'Python-UNO' bridge.

The FOCUS Kinetics Report first published in 2006 describes mathematical models and recommends statistical methods for the evaluation of chemical degradation data. This package implements fitting the kinetic models suitable for observations of the decline of a single chemical compound (no metabolite formation/decline or multi-compartment kinetics). Please note that no warranty is implied for correctness of results or fitness for a particular purpose. 'kinfit' is maintained, but not actively developed at the moment. Please check the 'mkin' package for an actively developed package for kinetic evaluations of degradation data.

Provides a general-purpose tool for dynamic report generation in R using Literate Programming techniques.

Chemical information from around the web. This package interacts with a suite of web APIs for chemical information.