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Comparison · Analytics

cIRT vs MultiSpline

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

Shared themes:r-package

cIRT vs MultiSpline: at a glance

FeaturecIRTMultiSpline
SectorAnalyticsAnalytics
Velocity score0.00.0
Sparks · 30d00
Top themesitem-response-theory, psychometrics, rcpparmadillo, maintenance-modesplines, multilevel-models, longitudinal-data, r-package
Last editorial update19m ago1h 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 MultiSpline?

MultiSpline went from five functions to a full multilevel spline framework in seven weeks.

MultiSpline fits spline-based nonlinear models to multilevel and longitudinal data in R. The package reached CRAN in February 2026 with five functions covering fitting, summary, prediction, plotting and intraclass correlations. Version 0.2.0, seven weeks later, adds cross-classified and nested random-effect structures, automatic knot selection, a multilevel R-squared variance partition, derivative-based interpretation with turning points, model comparison against polynomials, and cluster heterogeneity analysis, while keeping every 0.1.0 call valid.

Read the full MultiSpline trajectory →

cIRT vs MultiSpline: 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.

M
MultiSpline
ANALYTICS
0.0

MultiSpline went from five functions to a full multilevel spline framework in seven weeks.

◆ Current state

MultiSpline fits spline-based nonlinear models to multilevel and longitudinal data in R. The package reached CRAN in February 2026 with five functions covering fitting, summary, prediction, plotting and intraclass correlations. Version 0.2.0, seven weeks later, adds cross-classified and nested random-effect structures, automatic knot selection, a multilevel R-squared variance partition, derivative-based interpretation with turning points, model comparison against polynomials, and cluster heterogeneity analysis, while keeping every 0.1.0 call valid.

◆ Where it's heading

The arc is a research package being built out into a workflow at speed: 0.1.0 could fit a curve, 0.2.0 can tell you where the curve turns, how much variance each level explains, and whether a spline beats a polynomial at all. Backward compatibility was preserved across that expansion, which suggests the author is building for outside users rather than a single paper. The JOSS submission referenced in 0.1.1 points at academic distribution as the intended channel.

◆ Prediction

With the interpretation and diagnostics layers now in place, the next release will most likely extend the supported model families beyond the current lmer and glmer backends.

Alternatives to cIRT and MultiSpline

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 MultiSpline.

See all cIRT alternatives → · See all MultiSpline alternatives →

Recent activity from cIRT and MultiSpline

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

  1. 4mo agoMultiSplineCross-classified and nested structures turn MultiSpline into a framework
  2. 5mo agoMultiSplineMultiSpline v0.1.1
  3. 5mo agoMultiSplineMultiSpline v0.1.0 - Initial Release
  4. 5mo agoMultiSplinev0.1.0.1
  5. 10mo agocIRTArmadillo deprecations cleared, build config modernised
  6. 4y agocIRTperson() argument fix and dependency floor raise
  7. 6y agocIRTpkgdown site added, CI moved to GitHub Actions
  8. 7y agocIRTOpenMP enabled and the choice generation bug fixed
  9. 7y agocIRTcIRT 1.0.0: Initial Package Released to CRAN
  10. 7y agocIRTChoice matrix gains hard and easy question ids

Frequently asked questions

What is the difference between cIRT and MultiSpline?

Both compete on the same themes — r-package — within Analytics. cIRT and MultiSpline are shipping at a similar cadence (velocity 0.0 vs 0.0, both within Sparkpulse's "active" band). See the at-a-glance table above for a side-by-side breakdown of velocity, recent sparks, and editorial themes.

Is cIRT better than MultiSpline?

Sparkpulse doesn't pick a winner — we score release velocity, not feature parity. cIRT and MultiSpline are shipping at a similar cadence (velocity 0.0 vs 0.0, both within Sparkpulse's "active" band). 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 MultiSpline?

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