Changes in version 0.3-0                        

  - Major revision of the package, refactoring some crucial
    infrastructure. Rootograms and other visualizations are in topmodels
    (currently on R-Forge), see
    https://topmodels.R-Forge.R-project.org/articles/topmodels.html.
    Distribution functions (d/p/q/r) are in distributions3 (on CRAN),
    see https://www.zeileis.org/news/user2022/.

  - Also, data sets SerumPotassium and VolcanoHeights are now in
    topmodels.

  - Improved predict() method with more type of predictions, including
    moments (type = "mean" or "variance"), "quantile", "density",
    cumulative distribution function ("probability") etc. By default,
    the prediction is computed for the "full" outcome model (e.g.,
    hurdle or zero-inflation) but can also be just the "count" or "zero"
    component or the distribution "truncated" at zero.

                        Changes in version 0.2-1                        

  - Bug fix in dhpois() and dhnbinom() when x is a vector and pi is a
    scalar (reported by Andrea Gilardi).

  - Try to auto-detect columns in regressor matrices that are aliased,
    i.e., whose coefficients cannot be estimated. This is based on pivot
    and rank from qr() and can detect, e.g., constant or linearly
    dependent columns.

  - Catch errors when inverting the Hessian from optim, returning an NA
    matrix of correct dimension instead.

  - Conditionally register autoplot.rootogram() method.

                        Changes in version 0.2-0                        

  - New d/p/q/r/s functions for all combinations of Poisson vs. negative
    binomial (NB) and zero-truncated vs. zero-inflated vs. hurdle. The
    parameter names are all greek letters: lambda for Poisson mean, mu
    for NB mean, theta for NB dispersion, pi for zero-modification
    probability (either inflation or hurdle crossing). The theta
    parameter may also be called size for consistency with base R's
    nbinom family.

  - New generic function pit() for extracting the probability integral
    transform F(y) where F is the predicted cumulative density function
    and y the observed response.

  - Quantile residuals are now computed based on the pit() extractor.

  - New graphics function pithist() for PIT histograms based on pit().

  - New data set OralHealthNL accompanying Hofstetter et al. (2016):
    "Modeling Caries Experience: Advantages of the Use of the Hurdle
    Model", Caries Research, 50(6), 517-526. doi:10.1159/000448197

                        Changes in version 0.1-5                        

  - New d/p/q/r/s functions for the zero-truncated Poisson distribution
    where the parameter can either be specified in terms of the
    zero-truncated mean or the untruncated mean lambda.

  - New ztpoisson() family object for the estimation of zero-truncated
    Poisson regression model via glm().

                        Changes in version 0.1-4                        

  - New qresiduals() generic for computing (randomized) quantile
    residuals along with methods for various objects. (This is somewhat
    more flexible than statmod::qresiduals() which is not generic.)

  - A Q-Q plot based on quantile residuals is available in the new
    function qqrplot().

                        Changes in version 0.1-3                        

  - The hurdle() function now allows for the restriction of the theta
    parameter for the negative binomial distribution across the censored
    zero and truncated count components. The restriction is applied if
    dist = "negbin", zero.dist = "negbin", and separate = FALSE.

  - Bug fix in the computation of the standard error of log(theta) in
    zeroinfl() when with weighted data. The weights were used for the
    estimation of log(theta) but the standard error was not scaled
    accordingly.

                        Changes in version 0.1-2                        

  - The style and scale are now added as attributes to rootogram objects
    so that they can be re-used in the c() and + methods.

                        Changes in version 0.1-1                        

  - New data sets SerumPotassium, TakeoverBids, VolcanoHeights.

  - New function disptest() providing several (score) tests for
    over/underdispersion.

  - New rootogram() function with a wide range methods for creating
    rootograms based on various fitted model objects (fitdistr, glm,
    hurdle, zeroinfl, zerotrunc, ...)

  - FLXMRnegbin() driver for estimating mixtures of negative binomial
    models using flexmix.

  - MBnegbin(), MBztnegbin(), MBztpoisson() and MBbinomial() families
    for estimating boosted components of hurdle models using mboost.

                        Changes in version 0.1-0                        

  - Ported zeroinfl() and hurdle() along with corresponding vignette
    from pscl to countreg.

  - Added zerotrunc() for estimating zero-truncated count regressions.