NEWS

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PSTR 2.1.0

New features

• Parallel bootstrap support is migrated from the snowfall backend to the future and future.apply frameworks, enabling cross-platform parallel execution.
• Internal parallel helper functions are introduced to provide a unified interface for serial and parallel evaluation.

Improvements

• Bootstrap routines are refactored to use the new internal parallel helpers, simplifying the code base and removing backend-specific logic.
• Additional safeguards are implemented for parallel execution, including validation of the number of workers and protection against exporting excessively large globals.
• Documentation and examples are updated to reflect the new parallel infrastructure.

Bug fixes

• Minor robustness improvements in numerical routines, including safer handling of near-singular matrix inversion using an SVD-based pseudoinverse.
• Small fixes and consistency improvements across internal helper functions.

PSTR 2.0.0 (2026-02-27)

Breaking changes

• The internal architecture is fully refactored to an R6 design.
• Direct access to internal slots is no longer supported.
• Users relying on previous S3-style behaviour may need to update their code.

New features

• The PSTR class now follows an R6 design with reference semantics.
• The main modelling steps are implemented as class methods.
• Exported wrapper functions remain available for backward compatibility.
• The command line output is redesigned using the cli package.
• The print layout is modernised using knitr::kable.
• Separate print views are available for summary, tests, estimation, and evaluation.
• Internal getters and setters are added to support a clean R6 workflow.

Improvements

• Evaluation and bootstrap routines are rewritten under the R6 structure.
• Result objects are stored with consistent naming (tv, ht, wcb_tv, wcb_ht).
• Numerical robustness is improved in near-singular matrix inversion cases.
• An SVD-based pseudoinverse is used when necessary.
• Bootstrap routines use deep cloning to avoid overwriting the original object.
• Internal print helpers are reorganised into dedicated private methods.

PSTR 1.3.0

• fix the errors in R version 4.
• change documentation.

PSTR 1.2.5

• fix the bug in the function “plot_transition”.
• fix the bug in the function “plot_coefficients”.

PSTR 1.2.4 (2019-06-03)

• improve the plotting function “plot_transition” and “plot_response”.
• add new plotting function “plot_coefficients”.
• change documentation.

PSTR 1.2.3 (2018-12-09)

• fix some bugs found in the previous version.

PSTR 1.2.2

• fix some bugs found in the previous version.

PSTR 1.2.1 (2018-06-01)

• Link to the working paper.

PSTR 1.2.0

• New function “plot_response” which use the ggplot2 and plotly packages to plot the curve or surface of the expected response (contribution) against some variable and the transition variable.
• The estimation function “EstPSTR” will return the estimated time-invariante individule effects.
• The width of the separating lines in printing the results can adjust itself automatically to fit the width of the console.
• Rewrite the “version” function.

PSTR 1.1.0 (2017-09-25)

• Better documentation.
• In the function “EstPSTR”, now the initial value for “gamma” is allowed. The user can freely choose either “gamma” or “delta” to input for the estimation.
• Estimation of a linear panel regression model with fixed effects.
• The initial values can now be chosen automatically and will be returned after estimation.
• New function “plot_transition” which use the ggplot2 package to plot the estimated transition function.
• The package ggplot2 imported.
• A new data set “sunspot” included.
• Some bugs fixed.

PSTR 1.0.1 (2017-09-13)

• All the functions
• Documetation including README, LICENSE and etc.