qtl2fst
The out-of-memory backend for R/qtl2, feature-complete since 2020 and now purely on upkeep
Comparison · Analytics
cTMed vs PurpleAir
A side-by-side editorial comparison of cTMed and PurpleAir — release velocity, themes, recent moves, and the top alternatives to consider.
Shared themes:r-package
cTMed vs PurpleAir: at a glance
What is cTMed?
Continuous-time mediation effects get standardized centrality, six years into steady patch work
cTMed computes direct, indirect and total effects for continuous-time mediation models, with delta-method, Monte Carlo and bootstrap variants of each. Development is a long run of patch releases from the jeksterslab account, roughly every two months, each adding a function or two. The latest adds standardized centrality measures and allows a diagonal sigma across ten standardized estimators.
What is PurpleAir?
The R client for PurpleAir sensors keeps finding its time-averaging was wrong.
PurpleAir is a small R client for the PurpleAir air quality sensor API, covering sensor queries, historical readings, and — more recently — finding a sensor on the local network by IP address and id. Authentication has been simplified to an environment variable only, with the redundant key argument removed. The package is maintained reactively, and most of what ships is correctness work on the queries it already makes.
cTMed vs PurpleAir: editorial side-by-side
cTMed
2.5ANALYTICS
Continuous-time mediation effects get standardized centrality, six years into steady patch work
◆ Current state
cTMed computes direct, indirect and total effects for continuous-time mediation models, with delta-method, Monte Carlo and bootstrap variants of each. Development is a long run of patch releases from the jeksterslab account, roughly every two months, each adding a function or two. The latest adds standardized centrality measures and allows a diagonal sigma across ten standardized estimators.
◆ Where it's heading
The package is filling out a matrix rather than changing shape: for each effect type there is a delta-method, a Monte Carlo and a bootstrap path, and each release closes another cell. The 2025 releases were largely externally forced — an Armadillo 15.0.x transition at CRAN, a citation addition after the Psychological Methods paper landed — which suggests the statistical core has been settled since the 1.0.6 standardization revision.
◆ Prediction
The diagonal-sigma option has now reached the standardized estimators; extending it to the remaining unstandardized variants is the obvious next cell to fill.
PurpleAir
0.0ANALYTICS
The R client for PurpleAir sensors keeps finding its time-averaging was wrong.
◆ Current state
PurpleAir is a small R client for the PurpleAir air quality sensor API, covering sensor queries, historical readings, and — more recently — finding a sensor on the local network by IP address and id. Authentication has been simplified to an environment variable only, with the redundant key argument removed. The package is maintained reactively, and most of what ships is correctness work on the queries it already makes.
◆ Where it's heading
The recurring theme is time aggregation. Weekly, monthly and yearly average intervals were wrong and fixed in one release; the weekly average was wrong again and fixed in the next. For an air quality package that is not incidental — averaging window is what turns a stream of sensor readings into an exposure estimate, and downstream analyses inherit the error silently. The other thread is failing earlier and more clearly: explicit errors for spatial inputs the sensor query does not accept, better index parsing so malformed requests never reach the API, and handling for history calls that return nothing. Local sensor discovery is the one genuine capability addition, opening a path that does not depend on the cloud API at all.
◆ Prediction
On this record, further aggregation and input-validation fixes are the likeliest next releases; whether local network access grows past discovery into full local data retrieval is not something the entries indicate.
Alternatives to cTMed and PurpleAir
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 cTMed or PurpleAir.
mmconvert
A single-purpose mouse map interpolator that solved its problem in 2023 and has coasted since
qtl2convert
A conversion utility in pure maintenance mode, tracking R-devel breakage release by release
piecepackr
A board game graphics package runs one of the most disciplined deprecation cycles in R.
e2tree
The explainable-ensemble-tree package now measures whether its own explanations are faithful.
discretefdr
The discrete-data FDR package is being pared into one piece of a larger multiple-testing suite.
See all cTMed alternatives → · See all PurpleAir alternatives →
Recent activity from cTMed and PurpleAir
Latest ship moves from both products, interleaved chronologically. ⚡ = editorial spark.
- 27d agocTMedStandardized centrality measures and diagonal-sigma support
- 3mo agoPurpleAirWeekly averages fixed again; API key argument dropped
- 6mo agocTMedMinor method edits
- 10mo agocTMedPackage citation added for the Psychological Methods paper
- 10mo agocTMedArmadillo 15.0.x compatibility for CRAN
- 10mo agoPurpleAirLocal sensor discovery, and averaging intervals corrected
- 1y agocTMedStandardization reworked around the steady-state covariance matrix
- 1y agocTMedBootstrap centrality estimators and MCPhiSigma()
- 1y agoPurpleAirBounding box sensor queries fixed
Frequently asked questions
What is the difference between cTMed and PurpleAir?
Both compete on the same themes — r-package — within Analytics. cTMed is currently shipping more aggressively (velocity 2.5 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 cTMed better than PurpleAir?
Sparkpulse doesn't pick a winner — we score release velocity, not feature parity. cTMed is currently shipping more aggressively (velocity 2.5 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 cTMed?
Top cTMed alternatives in Analytics are ranked by recent ship velocity. Browse the "cTMed alternatives" section above for the current picks, or visit /alternatives/ctmed for the full list with editorial commentary on each.
What are the best alternatives to PurpleAir?
Top PurpleAir alternatives in Analytics are ranked by recent ship velocity. Browse the "PurpleAir alternatives" section above for the current picks, or visit /alternatives/purpleair for the full list with editorial commentary on each.