NEWS

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Colossus 1.5.2

• Added likelihood-based confidence intervals for logistic regression

Colossus 1.5.1 (2026-04-22)

• patch to fix errors on fedora-clang machines
• style updates based on lintr outputs

Colossus 1.5 (2026-04-17)

• partial matching added for many user inputs: control options, subterm types, term combinations, survival types, column names, etc

Colossus 1.4.11

• Convergence results now give feedback on what limit was hit
• Convergence result now also gives a measure of the change in Log-Likelihood in the last iteration
• Fixed bug in matched case-control in updating current best guesses

Colossus 1.4.10 (2026-02-20)

• Likelihood Ratio Tests probabilities corrected

Colossus 1.4.9 (2026-01-23)

• Plotting split into multiple specific functions
• Reduced time/memory use in stratified poisson modeling
• Bug fixes in relative risk calculation and plotting

Colossus 1.4.8

• Updated stratified poisson modeling to correctly update background strata risk levels
• Updated formula reading to not throw errors on long formulas

Colossus 1.4.7

• Updated behavior when negative risk is hit. Partial steps are now smaller, and the overall maximum step size will be checked during loop.
• Regressions that end after hitting a negative limit will now print a warning in the result table.

Colossus 1.4.6 (2025-12-16)

• Fixed bug in second derivative risk calculations, wrong correction to multi-term risk values.
• Improved results printing. Basic regression results only print term number column when multiple terms used. Likelihood boundary results now print the limit and score when negative limit hit.
• ncores option used for Colossus calculations now also applied to data.table operations. Previous number reset after calculations, may need to be manually reset if the regression hits an error.

Colossus 1.4.5 (2025-12-07)

• Updated geometric-mixture code to apply defaults of 0.5 theta and only excess terms
• Corrected normalization for intercept parameters

Colossus 1.4.4

• Corrected factorization not being applied to factored columns
• Fixed event assignment reordering the data
• Multiplicative and Multiplicative-excess models are now distinct. The default is left as multiplicative-excess.

Colossus 1.4.3 (2025-10-30)

• Logistic regression added
• Newton step calculation now checks the predicted change in score, and moves in opposite direction if the expected score is worse

Colossus 1.4.2

• Option added to normalize covariates, either scaled by the mean or maximum values.
• Gradient descent option now calculates standard error and covariance through second derivative after regression.

Colossus 1.4.1

• Formula input now allows more general applications of factor, ns(), bs(), I(var^n), interaction, etc.

Colossus 1.4.0

• Switch to formula inputs and model classes
• Removed unused functions, to simplify documentation

Colossus 1.3.1

• Convergence check performed more often
• Checks the actual maximum step taken to compare to threshold
• Previous versions may have run more iterations than necessary to meet derivative and step size thresholds

Colossus 1.3.0 (2025-06-05)

• Multiple realization code updated to improve speed
• lingering debugging variables removed: fir and der_iden

Colossus 1.2.2

• Additional code cleanup and minor utility function speed improvements

Colossus 1.2.1

• Matched Case-Control base code and equation vignette added

Colossus 1.2 (2025-02-13)

• Both Cox and Poisson functions now all return the expected information matrix derived covariance

Colossus 1.1.10

• Cox based functions updated to improve speed
• Additional curve solving output provided to give final window width and final step

Colossus 1.1.9

• Cox based functions switched covariance matrix calculation from negative inverse of log-likelihood second derivative, to expected information matrix.

Colossus 1.1.8

• Curve solving functions converted to c++ functions
• Testing scaled back to take up less time

Colossus 1.1.7

• Gradient descent algorithms tested further and presented in vignette
• Multiple realization function tested further

Colossus 1.1.6

• MacOS testing with OpenMP finished. MacOS use with OpenMP officially checked.
• By default the only systems that is forced to use single thread is linux using clang. This can be turned off by setting the "R_COLOSSUS_NOT_CRAN" environment variable.

Colossus 1.1.5.5

• Added CoxCurveSolver function to solve likelihood boundaries via bisection method

Colossus 1.1.5

• Started adding simplifications to allow for faster iterations
• Added simplification for linear ERR model
• Started gradient descent code
• Started external rate comparison options
• Added person-count and person-time table generation code and vignette

Colossus 1.1.4.2 (2024-10-21)

• R errors and warnings sent to stop() and warning(). C++ errors and warnings still controlled by verbosity argument
• ggsave defaults to width/height = 7
• Updates started to fix possible OpenMP issues with fedora 36 running clang 18
• Unable to have debug printing as an option and cover the c++ files with testing, but still have test output be readable. debug output removed.

Colossus 1.1.4.1 (2024-09-20)

• Cox plotting functions now return the tables used for plots (only last plot table returned)
• Plotting vignette updated to include more details and plots
• survival package listed as suggested for plotting vignette

Colossus 1.1.3 (2024-09-06)

• Cox regression now removes rows that end before first event and start after last event
• Cox regression now sets constant rows to be constant, helps with aliasing
• Tests now use sink() to avoid printing as much excessive output to console. Tests now consolidated further.

Colossus 1.1.2

• Log-likelihood bound functionality added
• subject to usual convergence issues, manual search option

Colossus 1.1.1 (2024-04-30)

• ggplot2 no longer required, now optional
• additional testing added for coverage
• default Makevars added via bash script

Colossus 1.1.0 (2024-04-03)

• Default Makevars is now fully portable
• By default only windows uses OpenMP now
• The GitHub version will include instructions on activating configuration to use OpenMP on gcc Linux

Colossus 1.0.5

• compilation flags changed to macros

Colossus 1.0.4

• utility checks updated to check term numbers and subterm types in R side
• code will fail if term numbers are not integers, term numbers are missing, or subterm types are

Colossus 1.0.3

• configuration script libraries moved from Suggested: to Imports:
• configuration script functions moved to non-exported functions in Colossus, circumvents note about imported libraries not being used and may be later used to provide the user with a function that informs them of why OpenMP is/isn't supported

Colossus 1.0.2

• utility checks updated to check that keep_constant is 0/1 values
• code will fail if keep_constant is not integer valued and 0/1, with explanation of why

Colossus 1.0.1 (2024-02-26)

• Configuration improved to detect compiler information
• Linux configuration depends on the system wide c++ default and the compiler used to compile R
• OpenMP support is not used if the c++ default or the R compiler is clang

Colossus 1.0.0 (2024-02-20)

• Initial submission
• C++ code modified to not apply OpenMP code if OpenMP isn't detected, to resolve MacOS installation failures

Colossus 0.9

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