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cfrnow vs constants

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

cfrnow vs constants: at a glance

Featurecfrnowconstants
SectorAnalyticsAnalytics
Velocity score5.00.0
Sparks · 30d00
Top themesepidemiology, bayesian-modelling, cfr-estimation, r-packagephysical-constants, codata, units, uncertainty-propagation
Last editorial update12h ago1h ago
WebsiteVisit →Visit →

What is cfrnow?

A Bayesian real-time CFR estimator that now ships stratified fits and posterior-predictive checks

cfrnow estimates case fatality ratios from line-list data while an outbreak is still running, using a Bayesian mixture-cure survival model registered as an `epidist` model type. Three releases in a month took it from first public release to stratified, partially-pooled fits with posterior-predictive checking. It leans on `distspec` for delay parameterisation, which reached CRAN alongside the 0.2.1 patch.

Read the full cfrnow trajectory →

What is constants?

The R package for CODATA constants rebuilt its symbol table on NIST's naming so future updates stop being hand work.

constants exposes the CODATA recommended values of the physical constants to R, as a data frame plus symbol lists that carry units, uncertainties, or both. The package reached 1.0.0 on the 2018 CODATA release and has shipped once since, purely to track a units package update. Its surface is small and its release cadence is bound to CODATA, which revises every few years.

Read the full constants trajectory →

cfrnow vs constants: editorial side-by-side

C
cfrnow
ANALYTICS
5.0

A Bayesian real-time CFR estimator that now ships stratified fits and posterior-predictive checks

◆ Current state

cfrnow estimates case fatality ratios from line-list data while an outbreak is still running, using a Bayesian mixture-cure survival model registered as an `epidist` model type. Three releases in a month took it from first public release to stratified, partially-pooled fits with posterior-predictive checking. It leans on `distspec` for delay parameterisation, which reached CRAN alongside the 0.2.1 patch.

◆ Where it's heading

The arc runs from producing a single corrected CFR number toward supporting a full model-checking workflow. 0.2.0 added the pieces a modeller needs to defend an estimate: replicate line lists replayed through the real-time truncation, an ascertainment-ratio correction for when fatal and non-fatal cases enter the line list at different rates, and per-group CFRs from `brms` formulas. Delay coverage widened from LogNormal and Gamma to Weibull in the same release.

◆ Prediction

Expect the next release to keep widening covariate and pooling support rather than adding new outcome types, since every 0.2.0 addition extended the existing formula interface instead of replacing it.

C
constants
ANALYTICS
0.0

The R package for CODATA constants rebuilt its symbol table on NIST's naming so future updates stop being hand work.

◆ Current state

constants exposes the CODATA recommended values of the physical constants to R, as a data frame plus symbol lists that carry units, uncertainties, or both. The package reached 1.0.0 on the 2018 CODATA release and has shipped once since, purely to track a units package update. Its surface is small and its release cadence is bound to CODATA, which revises every few years.

◆ Where it's heading

The direction set at 1.0.0 was to stop being a curated convenience wrapper and become a mechanical mirror of NIST. Hand-crafted symbol names were replaced with NIST's own ASCII symbols, categories adopted NIST's, and uncertainty switched from relative to absolute — all framed by the maintainer as necessary to make future CODATA updates routine. On top of that the package gained a correlation matrix and optional integration with the quantities package, moving it from a lookup table toward something that can propagate uncertainty.

◆ Prediction

Having rebuilt the symbol table specifically so CODATA revisions become mechanical, the next substantive release most likely tracks a new CODATA dataset rather than adding API. The experimental correlated-value support, disabled by default at 1.0.0, is the one part these entries flag as unfinished.

Alternatives to cfrnow and constants

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 cfrnow or constants.

See all cfrnow alternatives → · See all constants alternatives →

Recent activity from cfrnow and constants

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

  1. 5d agocfrnowdistspec dependency moves to CRAN
  2. 6d agocfrnowStratified CFR fits, Weibull delays, posterior-predictive checks
  3. 1mo agocfrnowFirst release: real-time CFR from a Bayesian mixture-cure model
  4. 5y agoconstantsCompatibility fix for units 0.7-0
  5. 5y agoconstantsconstants 1.0.0
  6. 8y agoconstantsUnit handling fixes ahead of the 1.0.0 rebuild

Frequently asked questions

What is the difference between cfrnow and constants?

They serve adjacent needs but don't currently overlap on shipped themes. cfrnow is currently shipping more aggressively (velocity 5.0 vs 0.0), with 0 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 cfrnow better than constants?

Sparkpulse doesn't pick a winner — we score release velocity, not feature parity. cfrnow is currently shipping more aggressively (velocity 5.0 vs 0.0), with 0 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 cfrnow?

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

What are the best alternatives to constants?

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