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cIRT vs tulpa

A side-by-side editorial comparison of cIRT and tulpa — release velocity, themes, recent moves, and the top alternatives to consider.

cIRT vs tulpa: at a glance

FeaturecIRTtulpa
SectorAnalyticsAnalytics
Velocity score0.07.5
Sparks · 30d02
Top themesitem-response-theory, psychometrics, rcpparmadillo, maintenance-modebayesian-inference, cran-release, r-packages, spatial-modeling
Last editorial update3d ago9h ago
WebsiteVisit →Visit →

What is cIRT?

A choice-based IRT model published once in 2019 and kept compiling ever since

cIRT implements Choice Item Response Theory, jointly modelling which item a respondent picks and how they perform on it — the setting where subjects choose between a harder and an easier question and the choice itself carries information. It comes out of the TMSA Lab, is built on Rcpp and RcppArmadillo, and has had one substantive release since reaching CRAN. Everything after early 2019 is build-system and toolchain upkeep.

Read the full cIRT trajectory →

What is tulpa?

The 0.0.x train stops at CRAN: tulpa's engine ships to the ecosystem it already anchors.

tulpa is the C++/R Bayesian spatial inference engine sitting under gcol33's family of ecological occupancy packages, tagging 0.0.x releases several times a week. 0.1.0 is its first CRAN release, and the notes state outright that the engine surface is unchanged from 0.0.198 — the work is packaging discipline: local T bindings rebound to n_t/n_times, OpenMP teams capped under R CMD check, the pkgdown deploy narrowed, an aspell dictionary added. The window behind it splits between the S3 generics conversion and numerical-correctness work in the nested-Laplace grid.

Read the full tulpa trajectory →

cIRT vs tulpa: editorial side-by-side

C
cIRT
ANALYTICS
0.0

A choice-based IRT model published once in 2019 and kept compiling ever since

◆ Current state

cIRT implements Choice Item Response Theory, jointly modelling which item a respondent picks and how they perform on it — the setting where subjects choose between a harder and an easier question and the choice itself carries information. It comes out of the TMSA Lab, is built on Rcpp and RcppArmadillo, and has had one substantive release since reaching CRAN. Everything after early 2019 is build-system and toolchain upkeep.

◆ Where it's heading

The package's whole functional history fits in a two-day window in January 2019, when the CRAN release and its immediate follow-ups were tagged in one batch, followed a day later by a release enabling C++11 and OpenMP and fixing the choice generation procedure. Since then the releases track other people's deprecations: Armadillo dropping conversions, RcppArmadillo requiring a different Makevars, R raising its floor. The 2025 release is entirely of that kind, down to swapping the README to Quarto.

◆ Prediction

The dependency floors were just raised to current Rcpp and RcppArmadillo, so the next release is most likely the one after Armadillo deprecates something else.

T
tulpa
ANALYTICS
7.5

The 0.0.x train stops at CRAN: tulpa's engine ships to the ecosystem it already anchors.

◆ Current state

tulpa is the C++/R Bayesian spatial inference engine sitting under gcol33's family of ecological occupancy packages, tagging 0.0.x releases several times a week. 0.1.0 is its first CRAN release, and the notes state outright that the engine surface is unchanged from 0.0.198 — the work is packaging discipline: local T bindings rebound to n_t/n_times, OpenMP teams capped under R CMD check, the pkgdown deploy narrowed, an aspell dictionary added. The window behind it splits between the S3 generics conversion and numerical-correctness work in the nested-Laplace grid.

◆ Where it's heading

Two moves in nine days point at the same destination: the generics conversion made tulpa extensible by downstream packages, and CRAN admission makes it installable by them. The current cadence — several tags a week, some existing only to record a measurement that produced no code change — does not survive CRAN's submission overhead, so the release rhythm has to slow whether or not the project intends it. The correctness work still clusters on the joint nested-Laplace driver, and 0.1.0 extends the same diagnostics habit with .NL_AXIS_SD_REASONS, a closed vocabulary for an outer axis whose grid does not contain its own posterior mode.

◆ Prediction

Expect tulpaObs to follow tulpa onto CRAN, since it is the consumer whose registrations the engine has spent this window unblocking, and expect the version line to move in larger, less frequent steps now that each one carries a submission.

Alternatives to cIRT and tulpa

Other Analytics products tracked by Sparkpulse, ranked by recent ship velocity. Each card links to a full editorial trajectory and lets you pivot into a head-to-head comparison with either cIRT or tulpa.

See all cIRT alternatives → · See all tulpa alternatives →

Recent activity from cIRT and tulpa

Latest ship moves from both products, interleaved chronologically. ⚡ = editorial spark.

  1. 18h agotulpaFirst CRAN release: engine surface unchanged from 0.0.198
  2. 4d agotulpatulpa_re_aghq() exposes the mode/theta cross-Hessian
  3. 8d agotulpaDense batched joint path could silently drop a grid cell
  4. 8d agotulpaCalibration and goodness-of-fit entry points become S3 generics
  5. 9d agotulpaCUDA backend had two definitions; link order decided if it ran
  6. 9d agotulpaHyperparameter bounds now flag when they leave the node range
  7. 10mo agocIRTArmadillo deprecations cleared, build config modernised
  8. 4y agocIRTperson() argument fix and dependency floor raise
  9. 6y agocIRTpkgdown site added, CI moved to GitHub Actions
  10. 7y agocIRTOpenMP enabled and the choice generation bug fixed
  11. 7y agocIRTcIRT 1.0.0: Initial Package Released to CRAN
  12. 7y agocIRTChoice matrix gains hard and easy question ids

Frequently asked questions

What is the difference between cIRT and tulpa?

They serve adjacent needs but don't currently overlap on shipped themes. tulpa is currently shipping more aggressively (velocity 7.5 vs 0.0), with 2 editorial sparks in the last 30 days against 0. See the at-a-glance table above for a side-by-side breakdown of velocity, recent sparks, and editorial themes.

Is cIRT better than tulpa?

Sparkpulse doesn't pick a winner — we score release velocity, not feature parity. tulpa is currently shipping more aggressively (velocity 7.5 vs 0.0), with 2 editorial sparks in the last 30 days against 0. For your specific use case, the alternatives sections above list other Analytics products to evaluate alongside.

What are the best alternatives to cIRT?

Top cIRT alternatives in Analytics are ranked by recent ship velocity. Browse the "cIRT alternatives" section above for the current picks, or visit /alternatives/cirt for the full list with editorial commentary on each.

What are the best alternatives to tulpa?

Top tulpa alternatives in Analytics are ranked by recent ship velocity. Browse the "tulpa alternatives" section above for the current picks, or visit /alternatives/tulpa for the full list with editorial commentary on each.