NEWS

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ShortForm 1.0.0.9000

ShortForm 1.0.0 (2026-09-10)

Breaking Changes

This release standardizes the three top-level algorithm functions’ arguments and, in a few cases, their names, so the same concept is expressed the same way regardless of which algorithm you’re calling.

• Renamed antcolony.lavaan() to antColony(), and tabuShortForm() to tabuSearch(), to match simulatedAnnealing()’s naming style. antcolony.mplus() and tabu.sem() (the lower-level Tabu function) are unchanged.
• Renamed antColony()’s antModel argument to initialModel, matching simulatedAnnealing()/tabuSearch().
• Unified item/factor specification across all three functions: antColony()’s list.items, full, i.per.f, and factors arguments are replaced by items (an optional flat vector of candidate item names, defaulting to colnames(data)) and itemsPerFactor (target item count per factor); factors is now always derived from initialModel’s syntax, the same way simulatedAnnealing() already did it. simulatedAnnealing()’s maxItems and tabuSearch()’s numItems are both renamed to itemsPerFactor to match, and tabuSearch() gains the same optional items argument.
• Renamed the iteration-count argument to maxIterations across all three functions (previously simulatedAnnealing()’s maxSteps, tabuSearch()’s niter, and antColony()’s max.run). antColony()’s steps argument (its separate, stagnation-based stopping rule) is unchanged.
• Unified bifactor to a character factor name (or NULL) across all three functions. simulatedAnnealing()/tabuSearch() previously took a logical flag and always assumed the last factor in the model syntax was the bifactor; they now name it explicitly, matching antColony()’s existing behavior.
• Replaced simulatedAnnealing()’s fitStatistic/maximize arguments with criterion/negateCriterion, matching tabuSearch()/tabu.sem(). criterion now accepts either a character fit-measure name (e.g. "cfi") or an arbitrary function for all three of simulatedAnnealing(), tabuSearch(), and tabu.sem() (previously function-only for the latter two).
• Removed antColony()’s summaryfile/feedbackfile arguments and their file-writing side effects; the same information is already available from the returned object’s summary/final_solution slots and the console progress output. Added a verbose argument (matching tabuSearch()) to control that console progress output.

Bugfixes

• Fixed tabuSearch crashing with “could not find function ‘%dopar%’” when run with parallel = TRUE under CRAN-style core-limited environments (e.g., when _R_CHECK_LIMIT_CORES_ is set)
• Fixed simulatedAnnealing hanging indefinitely when a candidate short-form change asked for more item swaps than a factor had available capacity
• Fixed tabu.sem crashing when a candidate neighbor failed to refit entirely, rather than just failing to converge
• Fixed tabu.sem crashing when every candidate neighbor was invalid or already on the tabu list
• Fixed antColony crashing when a partial lavaan.model.specs override was supplied, due to an internal default for ordered that didn’t match the function’s own documented default
• Fixed antColony silently dropping the group/group.label/group.equal/group.partial/group.w.free elements of lavaan.model.specs, due to a duplicated auto.var entry in its internal defaults and those elements never being wired into the underlying lavaan() call
• Fixed simulatedAnnealing producing a spurious “multiple local function definitions for ‘progressCallback’” NOTE under R CMD check, and restored its per-step “Current Step” progress output (previously assigned to an unreachable code path) for both serial and parallel runs
• Fixed simulatedAnnealing and tabu.sem crashing with “missing value where TRUE/FALSE needed” whenever a candidate (or the initial) model’s criterion value came back NA – most easily triggered by under-identified or poorly-specified models. An NA candidate is now always treated as worse than the current best, and an NA best is always displaced by any valid candidate.

Updates

• Reworked negateCriterion (tabu.sem, tabuSearch) so it genuinely controls whether the search looks for the largest or smallest value of the objective/criterion function, rather than requiring users to pre-negate their own criterion function beforehand
• Renamed tabu.sem’s obj argument to criterion, matching tabuSearch
• Changed tabuSearch’s default criterion from a pre-negated -cfi to plain cfi
• Extended partial lavaan.model.specs overrides (previously only supported by antColony) to simulatedAnnealing and tabuSearch, with new typo detection for unrecognized element names across all three algorithms
• Added a burn_in argument and whole-number axis ticks to simulatedAnnealing’s plot method
• Consolidated TS’s show/summary model-syntax reconstruction into one shared internal helper
• Function calls for simulatedAnnealing, tabuSearch, tabu.sem, and antColony are now captured with every argument resolved (specified or defaulted), including the actual merged lavaan.model.specs used
• Corrected @return documentation for tabu.sem, tabuSearch, simulatedAnnealing, and antColony to describe their actual S4 return types instead of stale list descriptions
• Consolidated the parallel cluster bootstrap/teardown boilerplate shared by antColony, simulatedAnnealing, and tabuSearch into shared internal helpers
• Replaced internal mapply(assign, ...) variable-splatting with do.call() (where the values were only ever fed into a single downstream lavaan() call) or plain named-list access (where a couple of values were unpacked for general use), removing several ad hoc internal environments in the process
• Added the selected criterion/fit-statistic and its final-model value to the show/summary output for SA, TS, and ACO objects
• Added a shared resolveCriterion() internal helper so criterion can be a character fit-measure name or a function everywhere it’s accepted
• Added vignettes

ShortForm 0.5.9

Note: v0.5.9 was an internal version only and was not released to CRAN; the changes below were included in the v1.0.0 release.

Bugfixes

• Fixed simulatedAnnealing crashing when run without maxItems (i.e., full-model rather than short-form usage)
• Fixed tabu.sem and tabuShortForm erroring instead of returning a result when no candidate model improved on the initial model
• Fixed simulatedAnnealing’s restart-after-stagnation logic throwing an error instead of restarting
• Fixed antcolony.lavaan’s stopping rule comparing the wrong ant solutions, and a warning/error check that could crash a run
• Fixed a bug where swapping an item for a short form could silently corrupt an unrelated item whose name happened to share a suffix (affected simulatedAnnealing and tabuShortForm)

Updates

• Consolidated the lavaan model syntax-building logic shared by the ACO, SA, and Tabu algorithms into common internal helper functions
• Added substantial unit test coverage for the top-level antcolony.lavaan, simulatedAnnealing, tabuShortForm, and tabu.sem functions
• Deprecated the shortForm argument in simulatedAnnealing; this is now determined automatically from maxItems

ShortForm 0.5.8 (2026-05-06)

Bugfixes

• Fixed issue in tabuShortForm for certain parallel workflows
• Fixed bug in tabuShortForm when using multidimensional models

Updates

• Removed dependencies on ggplot2, ggrepel, and tidyr (ACO and TS plot methods)
• Added some additional unit tests

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ShortForm 0.5.7 (2026-05-03)

Bugfixes

• Fixed issue in ACO algorithm where the best model was not properly updating
• Corrected use of ggplot within the ACO plot method due to depreciated ggplot2 functions
• Fixed issue in SA algorithm where models including factor relationships or outcome variables were not specified correctly after the initial model

Updates

• Modernized the README file
• Fixed CI/CD badge since Travis CI no longer works for this project

ShortForm 0.5.6 (2024-11-27)

• Updates focused on {antcolony.lavaan}.
  • lavaan.model.specs now defaults to the default arugments. If a user removes the arguments, they will be provided for them. If a user overwrites a specific argument (e.g., estimator = 'wls'), that will be respected.
  • Some minor adjustments to checking fitted models for specific warnings/errors that should result in better functioning when these do not exist.

ShortForm 0.5.5 (2024-06-05)

• Further updates to handle changes to lavaan error/warning messages more gracefully. These should continue into the future for the SA and ACo methods without additional issues.

ShortForm 0.5.4 (2024-05-22)

• Updates to handle changes to lavaan error/warning messages
• Fixed internal documentation to match current standards

ShortForm 0.5.3 (2023-12-13)

• Updates to antcolony.lavaan default lavaan.model.specs
• Spelling fixes
• Roxygen manual fixes

ShortForm 0.5.2 (2023-03-08)

Bugfixes

• This version fixes minor bugs, most associated with CRAN messages and warnings

ShortForm 0.5.0

Introduction of S4 Function Classes

• This version (re-)introduces classes to each of the main function outputs using S4 methods (instead of the S3 methods present in the prior version)
• Each method has a show (print), summary, and plot method that provides revamped, concise information about the algorithm
• Functions have been updated to accommodate these changes

Parallelized Short Form Functions

• Some short form functions have been modified to work with parallel processors, resulting in noticeably faster results particularly when the solution space is larger (e.g., more starting items) or with more complex models
  • This has resulted in some function argument changes. Please check any code that was written with older versions!

Minor cleanup

• Removed some unneeded code

ShortForm 0.4.6 (2020-03-13)

Updated argument check

• The argument check for fit statistics (ACO, SA) were updated to include fit statistics related to the “WLSMV” estimator (i.e, for ordered data).

Bugfixes

• A bug in the SA function that sometimes resulted in improper items has been fixed.

• A bug in the Tabu short form function that caused the Tabu list to be erased if the best criterion value was reached has been fixed.

ShortForm 0.4.5 (2020-02-25)

Extra arugment checks

• There are now additional checks for the function arguments related to the fit statistics (ACO, SA) and the fit statistic tests (ACO) with informative warnings for when the function arguments are not valid.

ShortForm 0.4.2 (2018-10-17)

Introduction of Function Classes

• This version introduces classes to each of the main function outputs (antcolony.lavaan == “antcolony”, simulatedAnnealing == “simulatedAnnealing”, tabuShortForm == “tabu”)

• This will allow for plot and print methods for each of these functions

Broken functionality: antcolony_plot

• The function antcolony_plot was replaced with plot.antcolony (aka, a plot method)

New functionality: S3 method for plotting

• With the addition of classes, a plot method and accompanying documentation has been added.

• Future updates will expand S3 methods for print() and summary()

Bugfixes

• Bugfixes to the main functions when using them to create shortforms of bifactor models.
• They should now produce actual bifactor shortforms (in 0.4.1, sometimes the item names would be cut off in later iterations $$FIXED$$ and the relationship between latent variables would be changed when they should have been kept constant $$FIXED$$).

Added a package loading message

• Now, when using an interactive R session, a package message is printed out (with a little Penguin holding it all up)!

ShortForm 0.4.1 (2018-06-13)

New functionality: Simulated Annealing

• The Simulated Annealing (SA) algorithm has been added to the package, with a single user-facing function simulatedAnnealing().
• SA can be used on anything lavaan can run, though the current implementation focuses on traditional confirmatory models using lavaan::cfa(). However, there are plans for more user control in the modeling process to allow for other model defaults.

New functionality: Tabu Search (Short Form)

• An adaptation of the Tabu search to short form creation has been added.

New functionality: ACO Plots

• The antcolony_lavaan() function has been modified so that it no longer will print a summaryfile.txt. Rather, the function maintains the old summary file as an internal object and returns it after completion,
• The new function antcolony_plot() takes the results from antcolony_lavaan() and creates three graphs: (a) a plot showing how pheremone levels change as the algorithm progresses, (b) a plot showing how the mean value of the regression coefficients changes as the algorithm progresses, and (c) a plot showing how the mean variance explained changes as the algorithm progresses.

New functionality: Bifactor Models

• Each of the short form functions utilizing lavaan (antcolony.lavaan(), simulatedAnnealing(), tabuShortForm()) are capable of handling bifactor models.
• In theory, this means relatively arbitrary models can be specified as well, but the functions utilize the “~” and “~~” operators for the additional functionality as well as the bifactor logical option. No guarantee that an arbitrary model will work beyond those currently tested.

Minor revisions

• The lavaan-based functions all have more controlled output to the R console. This is most noticeable with the antcolony.lavaan() function.

ShortForm 0.4.0 (2018-03-30)

New functionality: Tabu Search

• The Tabu search has been added to the package, with user-facing functions tabu.sem() and search.prep() for most of the heavy lifting and various helper and internal functions. The code was taken primarily from Carl Falk and Katerina Marcoulides (see Marcoulides, K. M., & Falk, C. F. (2018). Model Specification Searches in Structural Equation Modeling with R. Structural Equation Modeling: A Multidisciplinary Journal, 1-8.). These have been tested in limited circumstances, so please report any bugs as you find them!

Minor changes

• NEWS.md created.
• Description file updated.
• Authorship has been updated and URLs have been added to the ant colony functions.
• No bugs have been found in the package thus far, but just a reminder for any users that bug reports are helpful and welcome.