Changes in version 2.3.0 (2022-06-10)                  

    o   Added bootstrap confidence intervals (confint.moult function), estimates of covariance matrix and standard errors.

    o   Added dfbeta.moult function to check influence of individual observations.

    o   Updated predict.moult function.

    o   Components for likelihood function are calculated once and components to return are selected depending on type. 

    o   Fixed format error in help files.

                 Changes in version 2.2.1 (2022-02-09)                  

    o   Fixed error in as.vector(data.frame).

                 Changes in version 2.2.0 (2021-07-14)                  

    o   Fixed error in the calculation of SE(SD in start of moult). Thanks to Les Underhill and Tanya Scott for picking this up. 

    o   Moult scores in half steps can be converted to proportion of feather mass grown, e.g. "5 5 5 5 4.5 2 0 0 0" (ms2pfmg).

                 Changes in version 2.1.0 (2018-01-12)                  

    o   moult_alternative provides alternative parameterization, with halfway date instead of start of moult. Still in testing phase. At later stage will be incorporated into moult function.

    o   Addition of prec parameter to define measurement precision of moult index (proportion of feather mass grown). 

    o   Bug fix in type 3 likelihood, now more likely to complete optimization.

    o   New vignette for individual primary analysis.

                 Changes in version 2.0.0 (2016-05-05)                  

    o   Likelihood is calculated differently: not estimated by density but by integrating between y - 0.02 and y + 0.02, where y is the moult score, or PFMG.

    o   'moult' function now allows fixed parameters. 

                  Changes in version 1.4 (2014-10-08)                   

    o     -- Fixed error in predict.moult.

                  Changes in version 1.3 (2013-08-08)                   

    o     -- Bug fix: moult function did not work when added covariates for standard deviation in start date. 
	   Now works, but still only for categorical covariates. 
	-- Improved row and column names for covariance matrix of parameter estimates. 

                  Changes in version 1.2 (2013-01-16)                   

    o     -- Added reference to article in Journal of Statistical Software. 

                  Changes in version 1.1 (2012-06-23)                   

    o     -- The 'weaver' data set now contains only adult birds, and only observations 
	       from years 1988-2005.
	-- 'formula' in function 'moult' has changed to 'moult.index ~ days | x1 + x2 | y1 + y2 | z1', 
	       where the x's are covariates for duration, the y's are covariates for mean start date of 
	       moult and the z can be a single categorical covariate for the standard deviation in start 
	       of moult. 
	-- The above change depends on package 'Formula'. 
	-- 'moult' now has a 'data' argument, similar to 'lm' or 'glm'. 
	-- 'predict.moult' can now be used for predicting mean start dates at different covariate settings.