Canonical empirical examples: what can and cannot be compared
Source:vignettes/case-study-summary.Rmd
case-study-summary.RmdThe active freqTLS case-study sequence mirrors the pinned bayesTLS
supplement. The table keeps endpoint, response family, threshold,
and reference time visible because CTmax values defined for
different endpoints, thresholds, or durations are not automatically
comparable.
cases <- data.frame(
Case = c(
"Zebrafish oxygen", "Cereal aphids", "Snow-gum PSII",
"D. suzukii mortality", "D. suzukii awake/coma"
),
Dataset = c("zebrafish_o2", "aphid_tdt", "snowgum_psii",
"dsuzukii", "dsuzukii"),
Endpoint = c("survival", "survival", "retained PSII",
"mortality/survival", "awake/coma"),
Family = c("beta-binomial", "beta-binomial", "Beta",
"beta-binomial", "beta-binomial"),
Threshold = c("relative midpoint", "relative midpoint", "relative midpoint",
"relative CTmax/z; absolute LT50 point check", "relative midpoint"),
`t_ref (min)` = c(60, 60, 60, 240, 60),
Report = rep("CTmax and z (not Tcrit)", 5),
check.names = FALSE
)
knitr::kable(cases)| Case | Dataset | Endpoint | Family | Threshold | t_ref (min) | Report |
|---|---|---|---|---|---|---|
| Zebrafish oxygen | zebrafish_o2 | survival | beta-binomial | relative midpoint | 60 | CTmax and z (not Tcrit) |
| Cereal aphids | aphid_tdt | survival | beta-binomial | relative midpoint | 60 | CTmax and z (not Tcrit) |
| Snow-gum PSII | snowgum_psii | retained PSII | Beta | relative midpoint | 60 | CTmax and z (not Tcrit) |
| D. suzukii mortality | dsuzukii | mortality/survival | beta-binomial | relative CTmax/z; absolute LT50 point check | 240 | CTmax and z (not Tcrit) |
| D. suzukii awake/coma | dsuzukii | awake/coma | beta-binomial | relative midpoint | 60 | CTmax and z (not Tcrit) |
Scientific questions
- Oxygen-gradient zebrafish compare diploid normoxia and hyperoxia;
hypoxia is excluded because
zis weakly identified. - Cereal aphids compare species at age 6, then extend to all heat-branch ages.
- Snow-gum PSII compares Dark and Light recovery with a plant random
intercept on
CTmax. -
D. suzukii mortality reports the direct model’s relative
CTmaxandz, then cross-checks the four-hour absolute LT50 as an ML point. Its exact-model bootstrap interval is not reported because too few refits converged. -
D. suzukii awake/coma uses the first cell duration and
excludes duration zero because
log10(duration)cannot represent it; those controls are not evidence againstup. Censored time-to-coma and hurdle productivity remain bayesTLS-only.
Reading estimates across cases
z is expressed in degrees per order-of-magnitude change
in tolerated duration, but endpoint and model differences still matter.
CTmax is explicitly tied to t_ref and the
threshold. In particular, the four-hour mortality value must not be
ranked against one-hour relative-midpoint values as if all rows measured
one common trait. Cross-case displays must retain the columns above.
freqTLS adds Confidence Eyes, profile/Wald/bootstrap confidence intervals, likelihood contrasts, and explicit identifiability diagnostics. Those are frequentist extensions to the shared scientific examples, not substitute case studies.