Survival instinct: refusing to place a disc above its vertical-clear height extends life
web/content/research/TH-20260822-survival-instinct-vertical-clear-26f173b5.mdx and it will appear here. The registered record is shown below.The registered record
Claim
Survival instinct: when the next disc (value n >= 3) would land as the (n+1)-th or higher disc of a column it can never clear vertically, and refusing such placements at the root of the fair depth-4 search — leaving the search to choose among the remaining legal columns — extends mean paired lifetime and score on fresh development games relative to the unchanged search, by more than a 128-game paired cohort's detection floor.
Mechanism
Proposed by the repository owner from watching the depth-4 search: it places 3s and 4s above the row where they could ever clear vertically and dies under them a few rises later, while a human treats such a placement as a danger that must be cracked horizontally and avoids making it. The corpus analysis (RS-20260822T051732Z-ceb257d7) established that an entombed disc is present at 75% of depth-4 deaths with a median 11-move lead, and that the search's leaf already VALUES such positions correctly; what is untested is the ACTION: whether the move that creates the disc was avoidable at acceptable cost. A root-level refusal is the minimal form of an 'emergency mode' — a trigger computed from public state and a corrective constraint that overrides the search's preferred column — and its coverage (how often it overrides) is measured alongside its effect.
What would prove it wrong
- The strict-filter arm's paired score delta against the unchanged search on 128 fresh development games has a one-sided 95% bootstrap lower bound at or below zero, or a lower-quartile regression, or opposite-sign halves: refusing entombing placements does not help at this budget.
- The filter overrides the unchanged search's column in fewer than 2% of decisions: the rule rarely applies and cannot explain the observed deaths.
- If both arms lose on the mean but raise the lower quartile, the rule trades the upper tail for the floor, which finding-14 showed is the wrong trade for the million-point target; recorded as fail, not mixed.
- Coordinator's prior, stated before the run: the occupancy-matched corpus numbers (about two moves of life per entombed disc) predict an effect below the 128-game floor; a null here is expected and would be a non-measurement for effects under roughly 33,000 points.
Experiments that test it
- Paired SCREEN of fair D4 with the survival-instinct root filter (strict and literal) against unchanged fair D4 on 128 fresh development gamesfast-d4s5-survival-instinct-strict vs fair-d4 · SCREEN · completed
Results recorded against it
Held-out SCREEN of the survival-instinct root filter, depth 4 five strata, 128 paired never-read games 0xa52c0000+. STRICT (refuse a landing that is vertically dead AND entombed by its row): mean 346838 vs unchanged 348808, paired delta -1970 (bootstrap 95% bounds -27738 to +22313, paired sd 171933, floor 24999), W-T-L 41-26-61, moves 100.95 vs 101.32; the filter refused a column at 811 of 12922 decisions and overrode the unchanged search's column at 254 (1.97%), just under the preregistered 2% coverage bar, so the primary gate is recorded as INCONCLUSIVE by its own rule: the strict rule neither helps nor hurts measurably and rarely applies. LITERAL (the owner's wording, refuse every vertically dead landing that does not clear on arrival; secondary arm): mean 251744, paired delta -97064 (LB -136887, UB -59500), W-T-L 43-0-85, moves 75.67 vs 101.32, overrides 1243 of 9686 (12.8%): a clear, valid negative — forbidding vertically dead landings outright costs about a quarter of the game's length. Both arms: 0 incomplete and 0 illegal decisions.
- ✓CHECK gates passed before the lease was opened — observed: RUN-20260822T063817Z-a5d4c143: 7 of 7 (mask units re-run after a corrected test expectation)
- ✓incompleteDecisionsTotal 0 and illegalDecisionsTotal 0 — observed: 0 / 0
- ✕strict minus none: bootstrap and Student-t 95% lower bounds > 0 — observed: -27738 / -27150
- ✕strict minus none: Q25 >= and both halves > 0 — observed: Q25 delta -13513; halves +1721 / -5661
- ✕strict arm overrides >= 2% of decisions (else inconclusive) — observed: 254 of 12922 = 1.97%
Recorded metrics
- candidate
- name
- strict
- games
- 128
- score
- mean
- 346838.4609
- median
- 285244.5000
- sd
- 234288.6063
- q25
- 175358.2500
- min
- 86,228
- max
- 1,312,546
- moves
- mean
- 100.9531
- q25
- 55
- numberedClearsPerMove
- 2.0076
- coverRevealsPerMove
- 1.1163
- maxChainDepth
- 13
- meanOccupiedCells
- 23.8341
- censoredGames
- 0
- incompleteDecisions
- 0
- illegalDecisions
- 0
- gamesAtOrAboveMillion
- 1
- reference
- name
- none
- games
- 128
- score
- mean
- 348808.3047
- median
- 268,837
- sd
- 246206.6767
- q25
- 188871.5000
- min
- 103,221
- max
- 1,698,396
- moves
- mean
- 101.3203
- q25
- 55
- numberedClearsPerMove
- 2.0040
- coverRevealsPerMove
- 1.1149
- maxChainDepth
- 13
- meanOccupiedCells
- 24.0289
- censoredGames
- 0
- incompleteDecisions
- 0
- illegalDecisions
- 0
- gamesAtOrAboveMillion
- 3
- pairedScore
- n
- 128
- meanDelta
- -1969.8438
- pairedSd
- 171932.7446
- bootstrapLower95
- -27738.2355
- bootstrapUpper95
- 22313.0406
- studentTLower95
- -27150.1196
- studentTQuantile
- 1.6569
- detectionFloor
- 24998.8202
- detectionFloorNote
- 1.645 * sd / sqrt(n), the z-based floor defined in docs/research/status.md
- wins
- 41
- ties
- 26
- losses
- 61
- firstHalfMeanDelta
- 1721.0313
- secondHalfMeanDelta
- -5660.7188
- q25Delta
- -13513.2500
- largestSwings
- -844,875
- -805,407
- -548,601
- 505,964
- 486,921
- bootstrapSeedHex
- 0xb0071eaf
- resamples
- 20,000
- pairedMoves
- n
- 128
- meanDelta
- -0.3672
- pairedSd
- 46.6503
- bootstrapLower95
- -7.3516
- bootstrapUpper95
- 6.2109
- studentTLower95
- -7.1993
- studentTQuantile
- 1.6569
- detectionFloor
- 6.7829
- detectionFloorNote
- 1.645 * sd / sqrt(n), the z-based floor defined in docs/research/status.md
- wins
- 29
- ties
- 60
- losses
- 39
- firstHalfMeanDelta
- 0.7031
- secondHalfMeanDelta
- -1.4375
- q25Delta
- 0
- largestSwings
- -227
- -220
- -150
- 135
- 134
- bootstrapSeedHex
- 0xb0071eaf
- resamples
- 20,000
- coverage
- decisions
- 12,922
- triggeredDecisions
- 811
- overrides
- 254
- noColumnFallbacks
- 22
- candidate
- name
- literal
- games
- 128
- score
- mean
- 251744.0781
- median
- 236792.5000
- sd
- 112378.7779
- q25
- 159800.2500
- min
- 85,922
- max
- 628,660
- moves
- mean
- 75.6719
- q25
- 50
- numberedClearsPerMove
- 1.8787
- coverRevealsPerMove
- 1.0197
- maxChainDepth
- 11
- meanOccupiedCells
- 24.6577
- censoredGames
- 0
- incompleteDecisions
- 0
- illegalDecisions
- 0
- gamesAtOrAboveMillion
- 0
- reference
- name
- none
- games
- 128
- score
- mean
- 348808.3047
- median
- 268,837
- sd
- 246206.6767
- q25
- 188871.5000
- min
- 103,221
- max
- 1,698,396
- moves
- mean
- 101.3203
- q25
- 55
- numberedClearsPerMove
- 2.0040
- coverRevealsPerMove
- 1.1149
- maxChainDepth
- 13
- meanOccupiedCells
- 24.0289
- censoredGames
- 0
- incompleteDecisions
- 0
- illegalDecisions
- 0
- gamesAtOrAboveMillion
- 3
- pairedScore
- n
- 128
- meanDelta
- -97064.2266
- pairedSd
- 265747.3813
- bootstrapLower95
- -136887.3000
- bootstrapUpper95
- -59499.6051
- studentTLower95
- -135984.0518
- studentTQuantile
- 1.6569
- detectionFloor
- 38639.3588
- detectionFloorNote
- 1.645 * sd / sqrt(n), the z-based floor defined in docs/research/status.md
- wins
- 43
- ties
- 0
- losses
- 85
- firstHalfMeanDelta
- -71884.9844
- secondHalfMeanDelta
- -122243.4688
- q25Delta
- -29071.2500
- largestSwings
- -1,577,399
- -823,508
- -787,758
- -774,508
- -674,807
- bootstrapSeedHex
- 0xb0071eaf
- resamples
- 20,000
- pairedMoves
- n
- 128
- meanDelta
- -25.6484
- pairedSd
- 72.1942
- bootstrapLower95
- -36.4305
- bootstrapUpper95
- -15.4375
- studentTLower95
- -36.2216
- studentTQuantile
- 1.6569
- detectionFloor
- 10.4970
- detectionFloorNote
- 1.645 * sd / sqrt(n), the z-based floor defined in docs/research/status.md
- wins
- 42
- ties
- 10
- losses
- 76
- firstHalfMeanDelta
- -18.7656
- secondHalfMeanDelta
- -32.5313
- q25Delta
- -5
- largestSwings
- -425
- -225
- -212
- -210
- -185
- bootstrapSeedHex
- 0xb0071eaf
- resamples
- 20,000
- coverage
- decisions
- 9,686
- triggeredDecisions
- 3,470
- overrides
- 1,243
- noColumnFallbacks
- 497
- Single 128-game development-tier screen; the strict arm's effect, if any, is below the 25,000-point floor of this cohort.
- The strict coverage of 1.97% is within rounding of the 2% bar; the inconclusive label follows the preregistered rule literally rather than the spirit, and the deltas are reported in full.
- The screen ran after the evolution's own screen on the same otherwise idle machine; decisions are deterministic, wall times are not timing-grade.
- The literal arm's negative rejects the rule as a hard root constraint at depth 4; a soft penalty the search can weigh is a different candidate.