Understand the failure.
Verify the repair.
Small, reproducible software failures. The broken implementation, the fix that didn’t work, and the one that passed—preserved together.
Explore the cases ↓How results are verified ↗WHAT THE ARCHIVE CONTAINS
100840 executable cases. 20168 are open.
Every case records the implementation that fails, the fix that did not work, and the repair that passed its checks—with recorded outputs and source hashes. This release adds 100840 cases across 20168 failure mechanisms and 254 domains.
The open tier gives you the failure and the unsuccessful fix for one case in every mechanism. The remaining 80672 cases, 5 variants per mechanism, are member-only: the verified repair, its recorded checks, and the full fixture suite are held in the member archive. Read the methodology ↗
A RECORD OF WHAT WENT WRONG
Browse the archive / 100840
Two-sample mark-recapture abundance: chapman offset · case 01
Chapman estimates are one animal too high.
Two-sample mark-recapture abundance: chapman offset · case 02
Chapman estimates are one animal too high.
Two-sample mark-recapture abundance: chapman offset · case 03
Chapman estimates are one animal too high.
Two-sample mark-recapture abundance: chapman offset · case 04
Chapman estimates are one animal too high.
Two-sample mark-recapture abundance: chapman offset · case 05
Chapman estimates are one animal too high.
Two-sample mark-recapture abundance: chapman numerator · case 01
Chapman estimates are biased low, especially with few recaptures.
Two-sample mark-recapture abundance: chapman numerator · case 02
Chapman estimates are biased low, especially with few recaptures.
Two-sample mark-recapture abundance: chapman numerator · case 03
Chapman estimates are biased low, especially with few recaptures.
Two-sample mark-recapture abundance: chapman numerator · case 04
Chapman estimates are biased low, especially with few recaptures.
Two-sample mark-recapture abundance: chapman numerator · case 05
Chapman estimates are biased low, especially with few recaptures.
Two-sample mark-recapture abundance: variance denominator · case 01
Confidence intervals are far too wide.
Two-sample mark-recapture abundance: variance denominator · case 02
Confidence intervals are far too wide.
Two-sample mark-recapture abundance: variance denominator · case 03
Confidence intervals are far too wide.
Two-sample mark-recapture abundance: variance denominator · case 04
Confidence intervals are far too wide.
Two-sample mark-recapture abundance: variance denominator · case 05
Confidence intervals are far too wide.
Two-sample mark-recapture abundance: recapture feasibility · case 01
Impossible samples with more recaptures than animals caught are estimated.
Two-sample mark-recapture abundance: recapture feasibility · case 02
Impossible samples with more recaptures than animals caught are estimated.
Two-sample mark-recapture abundance: recapture feasibility · case 03
Impossible samples with more recaptures than animals caught are estimated.
Two-sample mark-recapture abundance: recapture feasibility · case 04
Impossible samples with more recaptures than animals caught are estimated.
Two-sample mark-recapture abundance: recapture feasibility · case 05
Impossible samples with more recaptures than animals caught are estimated.
Two-sample mark-recapture abundance: zero-recapture Petersen · case 01
A survey with no recaptures reports a finite abundance.
Two-sample mark-recapture abundance: zero-recapture Petersen · case 02
A survey with no recaptures reports a finite abundance.
Two-sample mark-recapture abundance: zero-recapture Petersen · case 03
A survey with no recaptures reports a finite abundance.
Two-sample mark-recapture abundance: zero-recapture Petersen · case 04
A survey with no recaptures reports a finite abundance.
Two-sample mark-recapture abundance: zero-recapture Petersen · case 05
A survey with no recaptures reports a finite abundance.
Lotka-Volterra competition outcome: species1 invasion criterion · case 01
Outcomes flip when competition coefficients are asymmetric.
Lotka-Volterra competition outcome: species1 invasion criterion · case 02
Outcomes flip when competition coefficients are asymmetric.
Lotka-Volterra competition outcome: species1 invasion criterion · case 03
Outcomes flip when competition coefficients are asymmetric.
Lotka-Volterra competition outcome: species1 invasion criterion · case 04
Outcomes flip when competition coefficients are asymmetric.
Lotka-Volterra competition outcome: species1 invasion criterion · case 05
Outcomes flip when competition coefficients are asymmetric.
Lotka-Volterra competition outcome: interior classification · case 01
Stable coexistence and founder control are swapped.
Lotka-Volterra competition outcome: interior classification · case 02
Stable coexistence and founder control are swapped.
Lotka-Volterra competition outcome: interior classification · case 03
Stable coexistence and founder control are swapped.
Lotka-Volterra competition outcome: interior classification · case 04
Stable coexistence and founder control are swapped.
Lotka-Volterra competition outcome: interior classification · case 05
Stable coexistence and founder control are swapped.
Lotka-Volterra competition outcome: interior equilibrium numerator · case 01
The coexistence abundance of species 1 is wrong whenever a12 differs from a21.
Lotka-Volterra competition outcome: interior equilibrium numerator · case 02
The coexistence abundance of species 1 is wrong whenever a12 differs from a21.
Lotka-Volterra competition outcome: interior equilibrium numerator · case 03
The coexistence abundance of species 1 is wrong whenever a12 differs from a21.
Lotka-Volterra competition outcome: interior equilibrium numerator · case 04
The coexistence abundance of species 1 is wrong whenever a12 differs from a21.
Lotka-Volterra competition outcome: interior equilibrium numerator · case 05
The coexistence abundance of species 1 is wrong whenever a12 differs from a21.
Lotka-Volterra competition outcome: neutral tie detection · case 01
A knife-edge isocline tie is reported as founder control or coexistence.
Lotka-Volterra competition outcome: neutral tie detection · case 02
A knife-edge isocline tie is reported as founder control or coexistence.
Lotka-Volterra competition outcome: neutral tie detection · case 03
A knife-edge isocline tie is reported as founder control or coexistence.
Lotka-Volterra competition outcome: neutral tie detection · case 04
A knife-edge isocline tie is reported as founder control or coexistence.
Lotka-Volterra competition outcome: neutral tie detection · case 05
A knife-edge isocline tie is reported as founder control or coexistence.
Lotka-Volterra competition outcome: coefficient validation · case 01
Species that do not compete at all are rejected as invalid input.
Lotka-Volterra competition outcome: coefficient validation · case 02
Species that do not compete at all are rejected as invalid input.
Lotka-Volterra competition outcome: coefficient validation · case 03
Species that do not compete at all are rejected as invalid input.
Lotka-Volterra competition outcome: coefficient validation · case 04
Species that do not compete at all are rejected as invalid input.
Lotka-Volterra competition outcome: coefficient validation · case 05
Species that do not compete at all are rejected as invalid input.
Schaefer surplus-production harvest reference points: maximum sustainable yield · case 01
MSY is double the surplus production possible at half capacity.
Schaefer surplus-production harvest reference points: maximum sustainable yield · case 02
MSY is double the surplus production possible at half capacity.
Schaefer surplus-production harvest reference points: maximum sustainable yield · case 03
MSY is double the surplus production possible at half capacity.
Schaefer surplus-production harvest reference points: maximum sustainable yield · case 04
MSY is double the surplus production possible at half capacity.
Schaefer surplus-production harvest reference points: maximum sustainable yield · case 05
MSY is double the surplus production possible at half capacity.
Schaefer surplus-production harvest reference points: effort at MSY · case 01
Effort reference points ignore gear catchability.
Schaefer surplus-production harvest reference points: effort at MSY · case 02
Effort reference points ignore gear catchability.
Schaefer surplus-production harvest reference points: effort at MSY · case 03
Effort reference points ignore gear catchability.
Schaefer surplus-production harvest reference points: effort at MSY · case 04
Effort reference points ignore gear catchability.
Schaefer surplus-production harvest reference points: effort at MSY · case 05
Effort reference points ignore gear catchability.
Schaefer surplus-production harvest reference points: collapse threshold · case 01
Excessive effort yields negative biomass and negative catch.
Schaefer surplus-production harvest reference points: collapse threshold · case 02
Excessive effort yields negative biomass and negative catch.
Schaefer surplus-production harvest reference points: collapse threshold · case 03
Excessive effort yields negative biomass and negative catch.
Schaefer surplus-production harvest reference points: collapse threshold · case 04
Excessive effort yields negative biomass and negative catch.
Schaefer surplus-production harvest reference points: collapse threshold · case 05
Excessive effort yields negative biomass and negative catch.
Schaefer surplus-production harvest reference points: equilibrium yield · case 01
Yields are inflated by a factor 1/q.
Schaefer surplus-production harvest reference points: equilibrium yield · case 02
Yields are inflated by a factor 1/q.
Schaefer surplus-production harvest reference points: equilibrium yield · case 03
Yields are inflated by a factor 1/q.
Schaefer surplus-production harvest reference points: equilibrium yield · case 04
Yields are inflated by a factor 1/q.
Schaefer surplus-production harvest reference points: equilibrium yield · case 05
Yields are inflated by a factor 1/q.
Schaefer surplus-production harvest reference points: status boundary · case 01
Fishing exactly at E_msy is labelled overfished.
Schaefer surplus-production harvest reference points: status boundary · case 02
Fishing exactly at E_msy is labelled overfished.
Schaefer surplus-production harvest reference points: status boundary · case 03
Fishing exactly at E_msy is labelled overfished.
Schaefer surplus-production harvest reference points: status boundary · case 04
Fishing exactly at E_msy is labelled overfished.
Schaefer surplus-production harvest reference points: status boundary · case 05
Fishing exactly at E_msy is labelled overfished.
Levins metapopulation with habitat destruction: habitat loss in colonisation · case 01
Destroyed patches are still colonised.
Levins metapopulation with habitat destruction: habitat loss in colonisation · case 02
Destroyed patches are still colonised.
Levins metapopulation with habitat destruction: habitat loss in colonisation · case 03
Destroyed patches are still colonised.
Levins metapopulation with habitat destruction: habitat loss in colonisation · case 04
Destroyed patches are still colonised.
Levins metapopulation with habitat destruction: habitat loss in colonisation · case 05
Destroyed patches are still colonised.
Levins metapopulation with habitat destruction: equilibrium destruction term · case 01
Equilibrium occupancy ignores habitat destruction.
Levins metapopulation with habitat destruction: equilibrium destruction term · case 02
Equilibrium occupancy ignores habitat destruction.
Levins metapopulation with habitat destruction: equilibrium destruction term · case 03
Equilibrium occupancy ignores habitat destruction.
Levins metapopulation with habitat destruction: equilibrium destruction term · case 04
Equilibrium occupancy ignores habitat destruction.
Levins metapopulation with habitat destruction: equilibrium destruction term · case 05
Equilibrium occupancy ignores habitat destruction.
Levins metapopulation with habitat destruction: extinction ratio · case 01
Equilibrium occupancy falls as colonisation improves.
Levins metapopulation with habitat destruction: extinction ratio · case 02
Equilibrium occupancy falls as colonisation improves.
Levins metapopulation with habitat destruction: extinction ratio · case 03
Equilibrium occupancy falls as colonisation improves.
Levins metapopulation with habitat destruction: extinction ratio · case 04
Equilibrium occupancy falls as colonisation improves.
Levins metapopulation with habitat destruction: extinction ratio · case 05
Equilibrium occupancy falls as colonisation improves.
Levins metapopulation with habitat destruction: occupancy ceiling · case 01
Occupancy exceeds the fraction of habitat that still exists.
Levins metapopulation with habitat destruction: occupancy ceiling · case 02
Occupancy exceeds the fraction of habitat that still exists.
Levins metapopulation with habitat destruction: occupancy ceiling · case 03
Occupancy exceeds the fraction of habitat that still exists.
Levins metapopulation with habitat destruction: occupancy ceiling · case 04
Occupancy exceeds the fraction of habitat that still exists.
Levins metapopulation with habitat destruction: occupancy ceiling · case 05
Occupancy exceeds the fraction of habitat that still exists.
Levins metapopulation with habitat destruction: extinction flow · case 01
Extinctions happen in empty patches.
Levins metapopulation with habitat destruction: extinction flow · case 02
Extinctions happen in empty patches.
Levins metapopulation with habitat destruction: extinction flow · case 03
Extinctions happen in empty patches.
Levins metapopulation with habitat destruction: extinction flow · case 04
Extinctions happen in empty patches.
Levins metapopulation with habitat destruction: extinction flow · case 05
Extinctions happen in empty patches.
INSPECTABLE BY DESIGN
Every result has a runnable source.
Runnable implementations with recorded outputs, source hashes, and explicit contracts. Related variants share a failure mechanism and belong together in evaluation splits.
Read the methodology ↗