| # MDM Coverage Experiments |
|
|
| CPU experiments and finite-state verification code accompanying the study of |
| accuracy--depth tradeoffs for parallel masked sampling. The repository contains |
| the source, frozen configurations, raw finite-dimensional results, arithmetic |
| certificates, logs, and publication figures for three experiment phases. |
|
|
| The experiments are deterministic finite sums, linear programs, and exact or |
| outward-rounded rational checks. They do not train a neural model and do not |
| require a GPU. They are diagnostic and verification artifacts for selected |
| finite instances; they are not a formal proof assistant, a global minimax |
| optimizer, or an empirical claim about natural-language models. |
|
|
| ## Repository layout |
|
|
| | Path | Contents | |
| | --- | --- | |
| | `src/`, `configs/` | Phase 1 model/execution diagnostics and randomized-policy LPs | |
| | `results/run-20260916-phase1-v1/` | Frozen Phase 1 source snapshot, JSON outputs, policies, logs, and figures | |
| | `phase2/src/`, `phase2/configs/` | Phase 2 finite witness search and independent certification | |
| | `phase2/results/run-20260916-phase2-certified-v2/` | Certified Phase 2 witnesses, certificates, recovery audit, and figures | |
| | `phase3/` | Phase 3 fixed-schedule comparison and biased-pair pilot | |
| | `phase3/results/run-20260916-phase3-v1/` | Frozen Phase 3 outputs, certificates, logs, and figures | |
| | `.venv/` | Original server-side virtual-environment wrapper, retained intentionally | |
| | `requirements.txt` | Minimal Python packages actually imported by the experiment code | |
|
|
| Each phase has a `PROTOCOL.md` describing its scientific scope, resource limits, |
| controls, and interpretation. Each frozen result directory contains a |
| `status.json` with source/configuration hashes and stage status. |
|
|
| ## Environment |
|
|
| The reported runs used: |
|
|
| - Python 3.13.13 |
| - NumPy 2.2.6 |
| - SciPy 1.17.1, including HiGHS |
| - Matplotlib 3.10.9 |
| - one CPU numerical-library thread |
| - no GPU |
|
|
| The committed `.venv` was created on the original Linux server with |
| `--system-site-packages`. It points to |
| `/root/userdata/liangyan/miniconda3/bin/python3.13`; therefore it is retained as |
| an environment artifact but is **not portable** to another server or operating |
| system. On the original server it can be activated with: |
|
|
| ```bash |
| cd /root/userdata/liangyan/mdm_coverage_experiments |
| source .venv/bin/activate |
| ``` |
|
|
| For a fresh clone, create a local environment instead: |
|
|
| ```bash |
| git clone git@github.com:yanliang3612/mdm_coverage.git |
| cd mdm_coverage |
| python3 -m venv .venv-local |
| source .venv-local/bin/activate |
| python -m pip install --upgrade pip |
| python -m pip install -r requirements.txt |
| ``` |
|
|
| Use a single numerical-library thread for every run: |
|
|
| ```bash |
| export OMP_NUM_THREADS=1 |
| export OPENBLAS_NUM_THREADS=1 |
| export MKL_NUM_THREADS=1 |
| export NUMEXPR_NUM_THREADS=1 |
| export MPLBACKEND=Agg |
| ``` |
|
|
| Basic checks: |
|
|
| ```bash |
| python src/check_environment.py |
| python src/verify_main_examples.py |
| python phase2/verify_exact_target_control.py \ |
| --source phase2/src/certify_witness.py \ |
| --output phase2/exact_target_control.json |
| ``` |
|
|
| ## Phase 1: model and execution diagnostics |
|
|
| Phase 1 contains three experiments: |
|
|
| 1. **E1:** model KL/TV versus the two-round all-A/all-B execution error. |
| 2. **E2:** self-generated pilot size, posterior drift, and output TV. |
| 3. **E3:** a small-dimensional occupation-measure LP over randomized adaptive |
| policies for a fixed oracle. |
|
|
| Run the complete Phase 1 pipeline with a new run identifier: |
|
|
| ```bash |
| python src/run_study.py \ |
| --config configs/phase1.json \ |
| --run-id run-YYYYMMDD-phase1-local |
| ``` |
|
|
| The runner executes regression checks, E1, E2, E3, and plotting in order. It |
| refuses to overwrite an existing result directory. To run individual stages: |
|
|
| ```bash |
| mkdir -p scratch/phase1 |
| python src/e1_model_execution.py --config configs/phase1.json --output scratch/phase1/e1.json |
| python src/e2_pilot.py --config configs/phase1.json --output scratch/phase1/e2.json |
| python src/e3_policy_lp.py --config configs/phase1.json --output scratch/phase1/e3.json |
| ``` |
|
|
| To regenerate figures for a completed run: |
|
|
| ```bash |
| python src/plot_results.py --run-dir results/run-YYYYMMDD-phase1-local |
| ``` |
|
|
| The original complete run is `results/run-20260916-phase1-v1/`. |
|
|
| ## Phase 2: finite all-policy witness search and certification |
|
|
| Phase 2 first searches a prespecified finite family using floating-point LPs, |
| then independently verifies selected witnesses using exact rational oracle |
| heads, a full-action Bellman recursion, downward-rounded probability flow, and |
| explicit logarithm enclosures. |
|
|
| Fast smoke run: |
|
|
| ```bash |
| python phase2/src/run_phase2.py \ |
| --config phase2/configs/phase2.json \ |
| --run-id run-YYYYMMDD-phase2-smoke \ |
| --smoke |
| ``` |
|
|
| Full search and certification: |
|
|
| ```bash |
| python phase2/src/run_phase2.py \ |
| --config phase2/configs/phase2.json \ |
| --run-id run-YYYYMMDD-phase2-full |
| ``` |
|
|
| The historical full run reached the 120-second limit for two selected K=4 LPs. |
| `finalize_phase2.py` performs only the narrowly scoped IPM recovery permitted by |
| the frozen protocol, preserves the original failures, and then reruns all exact |
| certification and plotting stages. The archived recovery chain can be replayed |
| to a **new** output directory with: |
|
|
| ```bash |
| python phase2/src/finalize_phase2.py \ |
| --base-run phase2/results/run-20260916-phase2-v1 \ |
| --output-run phase2/results/run-YYYYMMDD-phase2-certified-replay \ |
| --config phase2/configs/phase2.json \ |
| --reuse-retry phase2/results/retry-n16-B002-K4-ipm.json |
| ``` |
|
|
| The certified paper-facing run is |
| `phase2/results/run-20260916-phase2-certified-v2/`. Certification intervals are |
| deterministic arithmetic enclosures, not Monte Carlo confidence intervals. |
|
|
| ## Phase 3: schedule comparison and biased-pair pilot |
|
|
| Phase 3 reuses the nine certified Phase 2 witnesses. It compares geometric, |
| equal-size, exhaustive fixed-label, and randomized-label batch schedules, then |
| runs a bounded biased-representative experiment with an expanded pair-state |
| kernel. |
|
|
| The checked-in `phase3/inputs/` contains the frozen witnesses and certificates |
| used by the reported run. Run the full Phase 3 pipeline with: |
|
|
| ```bash |
| python phase3/run_phase3.py \ |
| --run-id run-YYYYMMDD-phase3-local |
| ``` |
|
|
| This runs the schedule benchmark, biased pilot, summary validation, and plots. |
| To use a newly certified Phase 2 run, replace the two frozen inputs first: |
|
|
| ```bash |
| cp phase2/results/RUN_ID/witnesses.json phase3/inputs/witnesses.json |
| cp phase2/results/RUN_ID/certificates.json phase3/inputs/certificates.json |
| ``` |
|
|
| To create a separate, data-identical presentation revision for a completed |
| Phase 3 run: |
|
|
| ```bash |
| python phase3/publish_figures.py \ |
| --run-dir phase3/results/run-YYYYMMDD-phase3-local \ |
| --plotter phase3/plot_phase3.py |
| ``` |
|
|
| The original complete run is `phase3/results/run-20260916-phase3-v1/`. |
|
|
| ## Output conventions |
|
|
| - Run identifiers must start with `run-` and must be unique. |
| - Runners create new directories and refuse to overwrite prior results. |
| - `status.json` is the authoritative completion record. |
| - Logs and failed cases are retained rather than silently discarded. |
| - PDF and 300-dpi PNG figures are both preserved. |
| - Exact certificates and floating-point exploratory diagnostics are labeled |
| separately. |
|
|
| ## Scientific scope |
|
|
| Phase 1 illustrates finite mechanisms. Phase 2 certifies all-policy error |
| brackets for selected finite exchangeable models but searches only a finite |
| outer family. Phase 3 compares restricted schedules and studies a small biased |
| model. None of these computations replaces the manuscript's analytic proofs, |
| establishes an asymptotic exponent by curve fitting, or certifies performance on |
| language data. |
|
|
| The plotting palette was inspired by |
| [`figures4papers`](https://github.com/ChenLiu-1996/figures4papers/); the numerical |
| methods and implementations are independent of that repository. |
|
|
| ## License |
|
|
| No software license has been added. Public visibility alone does not grant a |
| license to reuse the code. Add an explicit software license separately if |
| reuse permissions are desired. |
|
|
