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Comparison · Analytics
EpiNow2 vs xts
A side-by-side editorial comparison of EpiNow2 and xts — release velocity, themes, recent moves, and the top alternatives to consider.
EpiNow2 vs xts: at a glance
What is EpiNow2?
EpiNow2 unified its model interface, then went back to deepen the estimators behind it
EpiNow2 estimates reproduction numbers, infections and delay distributions from incomplete epidemiological reporting data. 1.8.0 was the structural turning point: every main modelling function now returns a consistent S3 object with `fit`, `args` and `observations`, reachable through shared accessors. The releases either side of it work on estimator quality — accumulation of irregularly reported data in 1.7.0, and a substantial expansion of `estimate_truncation()` in 1.9.0.
What is xts?
xts is finished software, and its releases now track R's C API more than user requests.
xts is the time-series class underpinning much of R's financial stack, and it behaves like infrastructure: the visible releases are bug fixes, plotting repairs and conformance work. A recurring thread is removing calls R no longer considers public — SET_TYPEOF in 0.14.0 and 0.14.1, then ATTRIB() and SET_ATTRIB() in 0.14.2. Feature additions are rare and small, the last cluster being open-ended time-of-day subsetting and na.fill performance in 0.13.0.
EpiNow2 vs xts: editorial side-by-side
EpiNow2
0.0ANALYTICS
EpiNow2 unified its model interface, then went back to deepen the estimators behind it
◆ Current state
EpiNow2 estimates reproduction numbers, infections and delay distributions from incomplete epidemiological reporting data. 1.8.0 was the structural turning point: every main modelling function now returns a consistent S3 object with `fit`, `args` and `observations`, reachable through shared accessors. The releases either side of it work on estimator quality — accumulation of irregularly reported data in 1.7.0, and a substantial expansion of `estimate_truncation()` in 1.9.0.
◆ Where it's heading
The package spent this window paying down interface debt and is now extending from the tidier base. Options that existed only for `estimate_infections()` have been propagated outward: `estimate_truncation()` gained the full `dist_spec` delay families, `obs_opts()` observation model selection between Poisson and negative binomial, and the `likelihood` and `return_likelihood` settings that make prior-only fits and loo-compatible output possible. Hardcoded assumptions are being replaced by specifiable ones in the same motion — the truncation model's additive noise term was a fixed `sigma ~ normal(0, 1)` prior and is now a `dist_spec` argument.
◆ Prediction
Expect the remaining modelling functions to keep converging on the shared options interface, since the last two releases have each moved another function onto it. A new `estimate_dist()` for interval-censored linelist data suggests delay estimation is the area still gaining surface.
xts
0.0ANALYTICS
xts is finished software, and its releases now track R's C API more than user requests.
◆ Current state
xts is the time-series class underpinning much of R's financial stack, and it behaves like infrastructure: the visible releases are bug fixes, plotting repairs and conformance work. A recurring thread is removing calls R no longer considers public — SET_TYPEOF in 0.14.0 and 0.14.1, then ATTRIB() and SET_ATTRIB() in 0.14.2. Feature additions are rare and small, the last cluster being open-ended time-of-day subsetting and na.fill performance in 0.13.0.
◆ Where it's heading
Two forces drive releases. R core keeps narrowing its public C API, and xts keeps rewriting internals to stay inside it; separately, ggplot-era changes elsewhere in the ecosystem surface plotting bugs that get fixed one report at a time. Nearly every entry credits an outside reporter, which is what maintenance of a dependency this widely used looks like.
◆ Prediction
Further C API conformance work is the safest expectation, since two consecutive releases have each removed a different non-API entry point and R has continued tightening that boundary.
Alternatives to EpiNow2 and xts
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 EpiNow2 or xts.
tidytransit
tidytransit tracks the GTFS spec as it grows, one reader and one router feature at a time.
oblicubes
A tiny grid renderer for oblique-projection cubes, complete since its first release.
biocro
BioCro swapped an unstable iteration for real root finders, changing what its crop models compute.
redist
redist keeps rewriting the sampler underneath a district-drawing API it has held stable since 4.0.
epiflows
epiflows has shipped four releases in eight years, none of which changed the code.
Recent activity from EpiNow2 and xts
Latest ship moves from both products, interleaved chronologically. ⚡ = editorial spark.
- 1mo agoEpiNow2estimate_truncation gains full delay and observation options
- 5mo agoxtsmulti.panel plots beyond 8 columns; SET_TYPEOF removed from C
- 5mo agoxtsATTRIB removed from C; rollapply.xts accepts vector widths
- 6mo agoEpiNow2Unified return objects and shared accessors across all models ⚡
- 1y agoEpiNow2Patch for an upstream rstan issue
- 1y agoEpiNow2Accumulation for irregularly reported data; unified priors
- 1y agoEpiNow2Matern kernel spectral density fix and GP prior revert
- 1y agoEpiNow2Gaussian Process model improvements and explicit defaults
- 2y agoxtsMulti-panel event lines; first SET_TYPEOF replacement
- 2y agoxtstclass changes now alter index values; log-scale y-axis added
- 3y agoxtsUpdate path for pre-0.12 objects missing index attributes
- 3y agoxtsOpen-ended time-of-day subsetting; fast scalar na.fill
Frequently asked questions
What is the difference between EpiNow2 and xts?
They serve adjacent needs but don't currently overlap on shipped themes. EpiNow2 and xts 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 EpiNow2 better than xts?
Sparkpulse doesn't pick a winner — we score release velocity, not feature parity. EpiNow2 and xts 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 EpiNow2?
Top EpiNow2 alternatives in Analytics are ranked by recent ship velocity. Browse the "EpiNow2 alternatives" section above for the current picks, or visit /alternatives/epinow2 for the full list with editorial commentary on each.
What are the best alternatives to xts?
Top xts alternatives in Analytics are ranked by recent ship velocity. Browse the "xts alternatives" section above for the current picks, or visit /alternatives/xts-r for the full list with editorial commentary on each.