Nous: Learning and Certifying Memory Decisions Before Source Calibration
Organizations: Department of Mathematics, Indian Institute of Technology Ropar
Abstract
Agent memory systems update state decisions from reports whose reliability may be unknown. Existing analyses of source estimation do not determine when a policy can be learned or its improvement certified without identifying the reporting channel. We study these three tasks using the same observed records. For a specified hidden Markov family with continuous source uncertainty, decision learning and powered certification have quadratic sample complexity, whereas fixed-precision source estimation has quartic complexity. We characterize a sharp identified interval for policy gain under an unknown shared-background channel and derive finite-sample certificates under bounded history dependence and conditional copying. Independently trained witness regions support general history spaces, and disagreement-conditioned auditing improves power for sparse revisions. For dependent histories, prediction-count-preserving batches cancel the unknown reporting background and admit conditional certificates. A MultiWOZ 2.4 evaluation uses text-processing policies on 1,000 human-written test dialogues with simulated audits. Balanced batches retain 2.26 percentage points of the full candidate's 7.34 percentage-point mean gain and obtain more positive certificates under weak audits. These results establish task-specific information requirements and provide an auditable policy-revision framework for Nous.
Figures & tables
| Unknown | Observable signal in the same record | Task complexity |
|---|---|---|
| Orientation | Learn: | |
| Policy improvement | Certify: | |
| Source scale | Estimate: |
| Study | Training | Development | Calibration | Test |
|---|---|---|---|---|
| Mutable state | 4,000 | 1,000 | 5,000 | 5,000 |
| MiniGrid | – | – | 5,000 | 1,000 |
| Learned witnesses | 4,000 | 4,000 | 8,000 | 5,000 |
| MultiWOZ | 8,438 | 1,000 | – | 1,000 |
| Method | Memory S7 | Memory S13 | S17 random |
|---|---|---|---|
| Arrival LWW | 61.67 1.63 | 60.97 0.81 | 61.17 1.50 |
| Constant zero | 50.83 0.85 | 49.93 1.27 | 49.70 2.51 |
| Native Nous / majority | 61.23 1.00 | 60.70 0.26 | 61.03 1.10 |
| Root-capped Nous | 75.50 1.32 | 74.17 0.72 | 73.63 1.42 |
| Single source 0 | 84.40 0.75 | 85.23 1.12 | 84.83 0.78 |
| Old gate vs. LWW | 61.67 1.63 | 60.97 0.81 | 61.17 1.50 |
| TV budget | Learned | Fixed coordinate | Whole history | Test gain (pp) |
|---|---|---|---|---|
| 0.00 | 4/4 | 4/4 | 0/4 | 28.82 |
| 0.03 | 4/4 | 0/4 | 0/4 | 29.39 |
| 0.10 | 0/4 | 0/4 | 0/4 | 27.84 |
| Slot | Nous | History | Full gain | Balanced gain | Revisions kept |
|---|---|---|---|---|---|
| Hotel area | 84.56 | 89.64 | 5.07 | 2.24 | 294/737 |
| Hotel price | 83.19 | 89.91 | 6.71 | 1.87 | 292/776 |
| Hotel parking | 88.28 | 95.40 | 7.12 | 1.65 | 227/725 |
| Hotel internet | 87.53 | 95.01 | 7.47 | 1.30 | 164/707 |
| Restaurant area | 81.77 | 90.75 | 8.98 | 3.21 | 460/1108 |
| Restaurant price | 82.55 | 92.45 | 9.89 | 3.38 | 426/1089 |
| Study | Method or comparison | Beneficial accepts | Harmful accepts |
|---|---|---|---|
| Mutable state | Unrestricted certificate | 9/9 | 0/9 |
| Mutable state | Report agreement | – | 9/9 |
| MiniGrid | Compatible vs. constant | 9/9 | – |
| MiniGrid | Compatible vs. LWW | 4/9 | – |
| Sparse revisions | Global certificate | 1,558/3,600 | 0/7,200 |
| Sparse revisions | Conditioned certificate | 2,720/3,600 | 0/7,200 |
| Control outcome | Reported count or bound |
| Initial beneficial acceptances | 0/1,800 |
| Initial null/harmful acceptances | 0/3,600 |
| Repeated-release false acceptances | 0/200 |
| Repeated-release upper bound (%) | 1.83 |
| Phase cells with complete acceptance | 23 |
| Phase cells with partial acceptance | 2 |
| Accepted comparison | Minimum tolerance (% TV) | Maximum tolerance (% TV) |
|---|---|---|
| Constant incumbent | 3.03 | 5.07 |
| LWW incumbent | 0.18 | 1.37 |
Appendix figures & tables18 assets
Supplementary material from the paper’s appendix.
Appendix
| Method | Independent | Copy | Delayed copy |
|---|---|---|---|
| Arrival LWW | 74.82 0.39 | 68.41 0.91 | 58.34 0.50 |
| Event-time latest | 74.82 0.39 | 68.41 0.91 | 67.91 0.43 |
| Original Nous updater | 77.86 0.14 | 67.72 0.94 | 55.81 0.86 |
| Root-deduplicated Nous | 77.86 0.14 | 74.51 0.71 | 73.78 0.81 |
| Current anchor | 85.31 0.26 | 80.10 0.92 | 80.03 0.81 |
| Current majority | 89.52 0.23 | 67.92 0.79 | 67.56 0.45 |
| Scenario | Run | Gain (pp) | 95% CI (pp) | Harmful / beneficial |
|---|---|---|---|---|
| independent | 1 | 19.76 | [18.52, 21.00] | 102 / 1090 |
| independent | 2 | 18.86 | [17.59, 20.13] | 144 / 1087 |
| independent | 3 | 18.82 | [17.56, 20.08] | 136 / 1077 |
| copy | 1 | 15.66 | [14.29, 17.03] | 277 / 1060 |
| copy | 2 | 17.52 | [16.15, 18.89] | 249 / 1125 |
| copy | 3 | 15.38 | [13.94, 16.82] | 350 / 1119 |
| Environment/run | Incumbent | Accepted | Gain (pp) | Paired 95% CI |
|---|---|---|---|---|
| S13/1 | LWW | 0 | 0.00 | [0.00, 0.00] |
| S13/1 | Constant | 1 | 23.70 | [20.46, 26.94] |
| S13/2 | LWW | 0 | 0.00 | [0.00, 0.00] |
| S13/2 | Constant | 1 | 24.10 | [20.90, 27.30] |
| S13/3 | LWW | 1 | 13.10 | [10.50, 15.70] |
| S13/3 | Constant | 1 | 24.90 | [21.60, 28.20] |
| Global bound | Conditioned bound | ||
|---|---|---|---|
| 2000 | 1 | 300 | 300 |
| 2000 | .25 | 58 | 300 |
| 2000 | .05 | 0 | 21 |
| 2000 | .01 | 0 | 0 |
| 8000 | 1 | 300 | 300 |
| 8000 | .25 | 300 | 300 |
| Slot | Nous | Last | Frequency | Recency .5 | Recency .8 | History |
|---|---|---|---|---|---|---|
| Hotel area | 84.56 | 83.78 | 83.41 | 84.01 | 83.41 | 89.64 |
| Hotel price | 83.19 | 82.76 | 81.17 | 82.39 | 81.31 | 89.91 |
| Hotel parking | 88.28 | 88.01 | 86.46 | 88.23 | 87.38 | 95.40 |
| Hotel internet | 87.53 | 87.57 | 86.07 | 87.75 | 86.91 | 95.01 |
| Restaurant area | 81.77 | 79.96 | 79.63 | 80.53 | 79.94 | 90.75 |
| Restaurant price | 82.55 | 80.41 | 79.58 | 81.48 | 80.39 | 92.45 |
| Slot | Specified values | State changes | ||
|---|---|---|---|---|
| Nous | History | Nous | History | |
| Hotel area | 22.83 | 52.52 | 27.75 | 40.53 |
| Hotel price | 21.68 | 52.90 | 29.77 | 48.09 |
| Hotel parking | 28.80 | 73.07 | 61.11 | 65.00 |
| Hotel internet | 23.75 | 70.55 | 54.26 | 71.28 |
| Restaurant area | 39.61 | 72.17 | 53.73 | 60.90 |
| Slot | Nous | Last | Frequency | Recency .5 | Recency .8 |
|---|---|---|---|---|---|
| Hotel area | 99.19 | 100.00 | 93.92 | 100.00 | 97.42 |
| Hotel price | 98.93 | 100.00 | 93.42 | 100.00 | 97.44 |
| Hotel parking | 99.24 | 100.00 | 94.74 | 100.00 | 97.73 |
| Hotel internet | 99.19 | 100.00 | 94.79 | 100.00 | 97.79 |
| Restaurant area | 99.27 | 100.00 | 93.45 | 100.00 | 97.25 |
| Restaurant price | 99.09 | 100.00 | 93.91 | 100.00 | 97.74 |
| Policy | Brier | Log loss |
|---|---|---|
| native nous | 0.2574 | 1.9914 |
| last report | 0.2496 | 0.5308 |
| frequency | 0.2273 | 0.8931 |
| recency 0.5 | 0.2617 | 0.5554 |
| recency 0.8 | 0.3807 | 0.7987 |
| history classifier | 0.1137 | 0.2266 |
| Balanced | Count-only | Full corrected | Oracle | Naive harmful | ||
|---|---|---|---|---|---|---|
| 0.3 | 0.00 | 241 | 98 | 0 | 691 | 582 |
| 0.3 | 0.03 | 102 | 31 | 0 | 642 | 677 |
| 0.3 | 0.10 | 5 | 0 | 0 | 328 | 700 |
| 0.6 | 0.00 | 688 | 629 | 0 | 700 | 0 |
| 0.6 | 0.03 | 656 | 523 | 0 | 700 | 0 |
| 0.6 | 0.10 | 404 | 192 | 0 | 699 | 0 |
| Setting | Value |
|---|---|
| Mutable-state runs | 9 |
| Mutable-state snapshots and sources per snapshot | 4 and 5 |
| Mutable-state copy probability | |
| Native Nous declared reliability | |
| HMM expectation-maximization iterations and restarts | 25 and 3 |
| Mutable-state audit |
| Replay quantity | Count or value |
| Mutable-state held-out queries | 45,000 |
| Selected HMM and suffix-two runs | 7 and 2 |
| Mutable-state split seeds | 36 |
| Mutable-state runtime (seconds) | 42.55 |
| MiniGrid test episodes | 9,000 |
| MiniGrid reconstructed certificates | 36 |
| Text-model or audit setting | Value |
|---|---|
| Maximum features per view | 35,000 |
| Maximum classifier iterations | 50 |
| Classifier regularization | |
| Classifier convergence tolerance | |
| Recency decay factors | |
| Candidate policies | 6 |
| Proposal | Retained revisions | Mean clean gain (pp) |
|---|---|---|
| Full candidate | 5,987 | 7.34 |
| Scored balanced | 2,236 | 2.26 |
| Count-only balanced | 2,243 | 1.77 |
| Reference signal | Scored balanced gain (pp) | Full corrected gain (pp) |
|---|---|---|
| 2.23 | 0 | |
| 2.26 | 5.25 |
| Dataset | Incumbent accuracy (%) | Candidate accuracy (%) | Outcome |
|---|---|---|---|
| EEG | 70.69 | 37.07 | Harmful acceptance |
| Occupancy | 55.36 | 99.49 | Beneficial rejection |
| Calculation quantity | Value |
|---|---|
| Specified laws | 27 |
| Null or harmful laws | 18 |
| Largest null or harmful acceptance probability |