ab8d3831212396166fc28d15a20acd138cbe7fed
1 Commits
| Author | SHA1 | Message | Date | |
|---|---|---|---|---|
|
|
f9f8d84671 |
TM diagnostics kit: VALIDATED (finds a known dead input), and it found a real bug
Built `common_libs/tm_diag/` as a first-class offline diagnostics kit for Tsetlin
work, BEFORE writing the new gun - because we hit two data problems tonight that no
amount of reading the TM's clauses would have revealed (a 38.8% majority answer,
and 36-58% mislabelled training samples).
WHAT IT PROVIDES
- `feature_spec.nim`: a NAMED feature container, so a learned clause prints as a
sentence (`IF near-wall AND bullet-dead-on AND turn-left(t-2) THEN class=3`)
instead of "feature 17". Includes the 49-bit draft spec from the design session
and the shipped 40-bit encoding.
- `tm_core.nim`: a compact deterministic Granmo multiclass TM with an
INTROSPECTABLE clause layout (mirrors the tm_pattern core).
- `diagnostics.nim`, six groups: (1) pre-flight DATA checks + shuffled-label
control, (2) clause introspection (readable dump, per-clause vote counts, empty
and never-fired clauses, length distribution, per-class balance), (3)
per-feature contribution with an explicit DEAD-INPUT LIST and a ranked
most-valuable list, (4) accuracy vs the majority baseline with per-class
precision/recall and pred-majority share, (5) learning curve, (6) ablation hooks
(drop a block / scramble a bit).
=== TASK 3: THE VALIDATION THAT GATES EVERYTHING - PASSED WITH NUMBERS ===
A diagnostic we never checked is worthless, so the kit was tested on a synthetic
set with a PLANTED RULE (class2 = A and B, class1 = A and not B, class0 = not A),
a deliberately IRRELEVANT block (US, 9 bits) and a PURE-NOISE bit (17).
- majority baseline 60.63% (class0); over-30% correctly flagged
- **the planted rule is recovered EXACTLY** via `necessaryLiterals`:
class0 IF NOT dist-wall<50 | class1 IF dist-wall<50 AND NOT lat DEAD-ON |
class2 IF dist-wall<50 AND lat DEAD-ON
- **DEAD-INPUT LIST = all 9 US bits AND the noise bit 17**, while the planted bits
0 and 45 are correctly NOT listed
- top contributors: bit0 w=1241.7, bit45 w=583.3, then 49.8 - a 12-25x gap, so the
relevant bits are unmistakable
- **ABLATION: drop WALLS -39.47pp, drop BULLETS -19.33pp, drop US 0.00pp**,
scramble A -42.00pp, scramble the noise bit 0.00pp
- shuffled-label control 60.40% vs majority 60.63% = -0.23pp -> no leak
So the kit reliably finds a known dead input and a known relevant one.
=== TASK 4: THE REAL READING, AND A BUG IN THE SHIPPED GUN ===
`tm_pattern` GF head, 6 DrussGT fixtures, pooled 250,745 samples:
- label balance c2 = **34.4%** (majority-heavy, flagged); accuracy **35.72%** vs
majority **34.24%** -> margin **+1.48pp**. On `tr_drussgt_vs_crazy` it is BELOW
majority (33.81% vs 37.72%, -3.92pp).
- 200 clauses: **27 empty, 45 never fired**, mean length 19.17, max 57. The
majority class is starved (class2: 22 non-empty, 18 empty, only 2 positive
fired). Class4 fires 11-24-literal clauses -> memorisation signature.
- **REPRESENTATION BUG FOUND (reported, not silently fixed):** `tmBuildBits` writes
only 38 raw bits into `var bits: array[TM_NBITS=40, uint8]` - bits 38 and 39 are
NEVER ASSIGNED, so they are always 0 and their negated literals are always 1.
The kit's `constantInputs` confirms 38/39 are constant, and **`UNUSED-38`/`39`
rank #6 and #8 in the most-valuable-inputs list** - i.e. the model's
highest-usage inputs are information-free. That is a representation bug, not a
display artefact, and it is a concrete mechanism for part of the poor learning.
DRAFT ENCODING CHECKED: the 49-bit draft is arithmetically consistent
(4+4=8 walls, 6+3=9 us, 3+5+3+3+3+3=20 motion, 5+7=12 bullets = 49). No draft
inconsistency.
Guards: test_tm_diag 48 (new), diag_synthetic 17 (new), test_gun_harness 39,
test_vbullet_metric 11, test_power_selection 3, test_adaptive_radar 41,
test_tfil_ring_weights 24, test_power_policy 26, test_ram_decision 40,
test_rack_membership 48, test_selector_tiebreak 19, test_tm_pattern_registration 20,
test_vbullet_admit_gate 12, acceptance_offline_vs_online 12/12; tm_pattern_learning
passes. The tm_pattern hook is additive and default-OFF (no behaviour change).
NOT YET INCLUDED (the automata metrics discussed for the next step): per-clause
automata settledness (distance from the flip point), clause diversity (pairwise
overlap), literal-set churn over time, and cross-clause vote disagreement. The kit
has clause-level diagnostics but not the automata-state ones.
|