NEWS

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AccelStab 2.3.1 (2025-07-01)

This is a minor release that changes the following...

step1_down() and step1_sample_mvt()

• Replaced sigma with chisq for multi-temperature models
• The residual error standard deviation (sigma) is now sampled from its own distribution rather than being treated as fixed.

step1_sample_mvt()

• Updated to align with step1_down()
• Added ... (ellipsis) to support optional arguments passed to minpack.lm::nlsLM() during model fitting.

excursion()

• Updated procedure for excursion() to draw from multi-t dist like used in step1_down() and step1_sample_mvt().

AccelStab 2.2.1 (2025-05-27)

• Fixed a minor plot issue in the vignette.

AccelStab 2.2.0 (2025-05-19)

This is a minor release which adds extra functionality to existing functions plus a vignette has been added that gives more background to the package.

Enhancements

step1_plot_diagnostic()

• Includes validation data in observed vs predicted and residuals vs predicted scatter plots, if provided.
• Adds a new plot: residuals vs time, color-coded by temperature, and includes validation data points when present.
• Vignette updated to reflect that the function now generates five plots (previously four).

Plotting Functions (step1_plot_CI(), step1_plot_desc(), step1_plot_PI(), step1_plot_pred(), step1_plot_T())

• xlim and ylim now truncate the visible plot area only, without removing data used in the plot.

Bug Fixes

step1_plot_diagnostic()

• Fixed QQ plot to show quantiles for all data, rather than temperature-specific quantiles.

step1_down() and step1_down_basic()

• Added ... to allow passing optional arguments to minpack.lm.
• When reparam = TRUE, now prints a message: default lower bounds are 0, but custom bounds may be specified.
• Fixed issue with Kelvin temperature inputs.

Documentation

• Updated function descriptions across all relevant functions for clarity and completeness.

AccelStab 2.1.1 (2025-01-20)

This is a minor release updating authors and email addresses

AccelStab 2.1.0 (2025-01-08)

This is a major release adding new functionality, adjusting the data sets and documentation.

New features

• step1_down_basic() This new function allows for rapid testing of the fit without all of the features.

• antigenicity Changed example data and added a validation column.

• step1_down() Adjusted the help page and added validation options to the examples. The function will now also return sampled parameters, reducing the need for the step1_sample_mvt function.

• step1_plot_diagnostic() Added argument to use either classic, standardized or studentized residuals.

AccelStab 2.0.2 (2024-10-21)

This release has a minor bug fix and additional descriptions added.

Bug fixes

• step1_sample_mvt() Fixed issue when no values at time point zero

• potency.rda File data adjusted slightly

• step1_down() Added to some arguments' description and new print when any of the k3 draws are below zero.

AccelStab 2.0.0 (2024-02-13)

This is a major release adding a few new functions and fixing a bug.

New features

• step1_down_rmse() added which allows the user to calculate the root mean squared error for their data and chosen parameters

• step1_down_diagnostic() added which allows the user to plot residual diagnostic plots after fitting the model

• step1_sample_mvt() added which allows the user to draw a chosen number of sample parameters from the multivariate t distribution for their own analyses

• step1_down() now accepts an extra argument validation which sidelines some of the data allowing the user to save it for testing purposes

• step1_plot_desc() now accepts an extra argument validation which sidelines some of the data allowing the user to save it for testing purposes

Bug fixes

• When selecting a temperature outside the data set for step1_plot_T() the colours of the prediction line and the ribbon are now consistent
• When using the argument temp_pred_C within step1_down() no longer are predictions duplicated if the temperature is already in the data
• Issue when no time = 0 rows present in the data and no parms provided to step1_down() now resolved

AccelStab 1.0.0 (2023-12-10)

• Added a NEWS.md file to track changes to the package.