## Changes in 'drc' 

2011-09-20: Problem with logDose argument in drm() and subsequent plotting haas been solved (reported by Ralf Schfer). 

2011-09-02: Constrained estimation uses the actual limits provided (bug report by Andrew Kniss).

2011-08-31: The functions genLoewe(), genLoewe2(), genBliss(), genBliss2(), and ursa() have been improved w.r.t. starting values. The model specification has also been simplified.

2011-08-24: genBliss() and genBliss2() has been updated (after suggestions from Hugo Ceulemans). Functions iceLoewe1() and iceLoewe2.1() have
benn added.

2011-08-23: Error in ED calculation for the logistic models (e.g., L.4()) has been fixed (after a report from Daniel Gerhard).
Error caused by update of the function deltaMethod() in alr3 has been fixed.

2011-07-04: Small changes for the anova method. Adding df for event time and Poisson models.

2011-07-01: Small update in the calculation of confidence intervals (after a suggestion from Scott Ray). 

2011-06-24: The model function W2x.4() has been added (after a suggestion by Ccile Cornou).

2011-05-24: Small improvement in the calculation of ED value for the log-normal and Weibull type 2 models. 
"display" and "type" arguments have been added to maED(). 

2011-05-19: The argument "type" can now also take the value "event" for fitting event times. 

2011-05-10: The help page for spinach has been improved.

2011-05-02: Simplifying the R lines in print.summary.drc() for printing the summary output of a model fit.

2011-05-02: The self starter function for llogistic models can now handle infinite dose values (after a report from Marc Weimer).

2011-04-09: multdrc() has been completely removed. 

2011-04-04: The model function weibull2x() (a model including a sort of "lag time" parameter) 
has been added (after a suggestion by Ccile Cornou).

2011-03-23: A small bug in ED() has been fixed (after a report from Nathan Pace).

2011-03-09: The BIC method has been removed (after suggestion from Prof. Brian Ripley).

2011-02-04: The functions isobole() and mixture() have been modified in order to fix an error in the plotting of
the isoboles (after a report from Andreas Betz).

2010-12-16: The model function genursa2() has been replaced by actimL().

2010-12-14: The model genursa2() for fitting the generalized URSA model has been included (after an idea by Hugo Ceulemans).

2010-12-10: The model genursa() for fitting the generalized URSA model has been included (after an idea by Hugo Ceulemans).

2010-12-09: The model function genBliss(), genBliss2(), and genLoewe2() for fitting generalized Bliss independence and Loewe additivity with different maxima has been included (after an idea by Hugo Ceulemans). 

2010-11-23: The model function genLoewe() for fitting generalized Loewe additivity has been included (after an idea by Hugo Ceulemans). 

2010-11-16: Small improvement in the summary output. Now the actual curve names are used.

2010-11-11: A small bug in ED() (mismatch of curve names and parameter estimates) has been fixecd (after a report from Andreas Betz). 

2010-11-03: A small bug in the plot produced by isobole() has been fixed (after an inquiry from Andreas Betz). 

2010-10-12: A bug in the calculation of standard errors in SI() has been fixed (after a report from Andrea Onofri).

2010-09-23: mselect() has been extended to include an argument for specifying the type of information criterion to use. 

2010-09-20: maED() has been extended to include simple linear regression.

2010-09-16: mselect() has been extended to include a few standard polynomial regression models. 

2010-08-03: Studentised residuals are now also available for binomial responses (after an inquiry from Stuart Rosen). 

2010-06-04: Studentised residuals are now also available (after an inquiry from John). 

2010-06-02: ED values are now correct for cedergreen() models (after a bug report by Claire Della Vedova). 

2010-05-31: Small bug in plot.drc() related to "xt" and "xtlab" arguments has been fixed (after a comment by Anja Coors). A small bug in comped() has also been fixed (after a question from Jochen Zubrod). 

2010-05-06: The argument "clevel" has been added to ED(). The function maED() has been extended and now also handles model fits 
involving several curves (after a suggestion from Andre Kleensang). 

2010-04-29: Dataset 'ecvam' has been removed. The mixdrc() function has been temperarily removed. 

2010-04-23: Minor bug in the predict method has been fixed. This means that type="bars" in the plot method now works again 
(after a bug report by Andy Robinson). 

2010-04-16: The help for NEC() has been improved (after a question from Ins Gonzlez). 

2010-04-15: The comped() has been re-introduced (after suggestion from Jochen Zubrod). 

2010-03-17: logLik has been extended with a "nobs" attribute (provided by Tobias Verbeke). A S4 BIC method has been added 
(also provided by Tobias Verbeke). 

2010-03-12: The help page of drm() has been improved a bit w.r.t. the use of weights (after a question by Xuesong Yu). 

2010-03-10: A slight modification in vcov.drc() to suppress unnecessary error messages (reported by Xuesong Yu). 

2010-01-26: A slightly different bisection method has been implemented in ursa(). The corresponding help page has also been extended (more example lines). 

2010-01-13: The model function ursa() for describing combination effects has been added (after an idea by Hugo Ceulemans). 
The help page for MM.2() and MM.3() has been improved. 

2010-01-11: The model function cedergreen() has been updated to ensure correct calculation of ED values (reported by Claire Della Vedova). 

2009-11-17: The help page of drm() has been updated. 

2009-10-13: confint has been improved to automatically use the appropriate reference distribution for the confidence intervals; 
Internal structure of ED() has also been modified (reported by Marc Weimer). 

2009-10-12: The self starter for twophase() has been slightly improved. 

2009-09-03: The functions NEC.2(), NEC.3(), NEC.4() for estimation of no effect concentration have been included (after an idea by Ralf Schaefer). 

2009-09-03: The function comped() has been removed. 

2009-09-02: The argument "extended" has been added to the function maED(). 

2009-09-01: The model function twophase() based on log-logistic models has been added (after an idea by Ida Katarina Auf der Maur Hindrichsen). 

2009-07-28: Small bug in cedergreen() and ucedergreen() related to calculation of ED values has been fixed (reported by Clare Della Vedova). 

2009-07-27: Small bug in the function modelFit() has been fixed (after feedback from Heike Schmitt). 

2009-07-27: Help page for CRS.5a has been improved (after comment from Claire Della Vedova). 

2009-07-06: The functions lin.test(), mr.test(), and neill.test() have been added. 

2009-06-30: The data frame etmotc has been included. 

2009-06-08: The argument 'display' (with same functionality as in Ed()) has been added for compParm() (after a suggestion from Scott Ray). 

2009-06-02: The help pages for anova.drc and BC.4(), BC.5(), CRS.5.() have been improved. 

2009-05-29: The dataset ecvam has been included (migrated from the package 'mrdrc'). 

2009-05-28: The function maED() for parametric model averaging has been added. 

2009-05-27: The functions fplogistic() and FPL.4() enable fitting dose-response models based on fractional polynomials. The function maED() 
can be used to do model-average based estimation of ED values. 

2009-05-24: Structure of self starter functions has been completely revamped. Four initial value procedure are now available for 
almost all implemented dose-response models. 

2009-05-23: The function getInitial() has been included. 

2009-05-20: Help page for ED() has been improved (after comment from Claire Della Vedova). 

2009-05-07: Bug in ED() concerning the arguments type="absolute" and reference="upper" has been resolved (reported by Yue Zeng-Li). 

2009-04-22: Help page for gompertz() has been improved slightly. 

2009-04-08: Help page for earthworms dataset has been improved. Error in likelihood calculation for some binomial models has been fixed. 

2009-04-07: mixture() also works for binomial data. Argument "legendCex" in the plot method renamed into "cex.legend" in line with other cex arguments. 

2009-04-01: Minor internals changes in drm() and in the plot method. 

2009-03-27: The convenience functions b.3(), B.3(), b.4(), B.4(), b.5(), B.5(), and boltzmann have been removed. Use L.3(), L.4(), and L.5() instead. 
compParm(), ED(), SI() have been  restructured. drm() has been extended to allow fitting models separately for each curve. 
confint, summary, vcov, ED, MAX, SI have a new argument "pool" to allow pooling of separate fits. Argument "ci" in relpot() and SI() has 
been renamed into "interval". modelFit() now also works for binomial data. 

2009-03-25: The dataset "algae" has been included. vcov method has been re-structured. 

2009-03-24: The function plotraw() has been removed. Initial plots of the data should be done using R's standard plotting functionality, 
e.g. plot and xyplot(). 

2009-03-19: The argument "conLevel" has a more sensible default (no longer hardcorded at 0.01). The argument "xsty" has been introduced 
to control the arrangement of tick marks on the dose axis. 

2009-03-17: The function yieldLoss() has been included to handle a different parameterization of the Michaelis-Menten model 
(after a suggestion by Andrew Kniss). 

2009-03-11: The argument "fctList" has been removed from drm(). 

2009-03-06: mixture() has been completely revised with a lot of changes to the arguments. The model function richards() has been removed 
as it is simply a different parameterization of the five-parameter log-logistic model. colFct() has also been removed. 

2009-03-04: A new function modelFit() has been introduced for assessing the model fit, partly replacing the anova method. 

2009-02-27: Bug in mselect() has been fixed (reported by John Lewis). 

2009-02-25: Bug in boxcox.drc has been fixed. Moreover, this method has been extended to include functionality previously available through drm(). 

2009-02-19: multdrc() and associated mdControl have been taken completely out of use. drm() has been improved w.r.t. handling extremely 
small or large dose or response values. Arguments "lowerc" and "upperc" have been removed in model functions as they were redundant. 

2009-02-13: Argument "ci" renames into "interval" in ED(). 

2009-02-12: Bug in predict.drc fixed (thanks to Mario D'Antuono). 

2009-02-09: Redundant encoding removed. Argument "fixed" added to BC.4() and BC.5() (thanks to Nina Cedergreen). 

2008-12-02: Dataset "H.virescens" added. Asymptotic regression and exponential decay implemented differently. 

2008-11-26: "lnormal" function has been added plus three new datasets. 

2008-11-18: "gompertz" function has been added. 

2008-11-13: Error in level argument in plot method has been fixed. 

2008-11-03 Datasets 'lepidium' and 'nasturtium' have been added. 

2008-10-31: Bug in 'level' argument in plot method has been fixed. 

2008-10-02: New function mrdrm() for model-robust modelling included. Accompanying ED and predict methods also added. 

2008-09-30: The lettuce dataset got correct row numbers. 