Issue: #30
Status: Synthetic experiment implementation; not yet evidence about real coding agents.
When does controlled stochastic diversity improve verified outcomes compared with simply replicating the same worker?
The experiment is intentionally designed so that it can report that diversity hurts. Agent count is not treated as a proxy for intelligence.
The R1 runner compares six conditions:
single_deterministic — one worker, deterministic scheduler;identical_replication — N equal workers with maximally correlated base errors;seed_only — N equal workers with partial stochastic decorrelation but the same structural label;structural_diversity — N structurally distinct labels with lower configurable error correlation;bandit_selected — Thompson sampling chooses a fixed-size subset from a larger heterogeneous pool;diverse_random_verifiers — structurally diverse workers plus randomized assignment across independent verifier identities.Conditions 2–6 use the same fixed attempt budget N except that the single-worker baseline intentionally uses one attempt.
This first synthetic model does not claim to model real differences between models, prompts, tools, or organizations. Structural diversity is represented by distinct labels and a separately controlled error-correlation parameter.
That separation matters:
seed variation != structural diversity != low error correlation
The experiment records all three rather than collapsing them into one number.
A synthetic worker first produces a base-success outcome under the shared correlation environment. A selected candidate then receives additional synthetic checks:
A candidate is ground-truth is_good only when it succeeds, passes the hidden check, and has no regression or security failure.
These are experiment variables, not claims about actual defect distributions in coding agents.
A verifier has:
Verifier decisions can be partially correlated within a task. The randomized-verifier condition distributes candidates over several verifier identities, each with its own per-task shared draw.
The integration policy selects the first candidate accepted by its assigned verifier. This intentionally makes false acceptance measurable rather than assuming that the simulator has a perfect selector.
Each condition records raw seeded trials and, optionally, raw per-task candidate records.
Primary metrics include:
Every across-trial metric reports mean, sample standard deviation, min/max, and a descriptive normal-approximation 95% interval. Raw trials remain available and should be preferred for serious analysis.
Every non-replication condition is compared with identical_replication. The machine-readable result includes:
delta_mean_verified_success_rate
lower_success_than_replication
delta_mean_verified_utility_per_unit_cost
lower_utility_than_replication
No code path rewrites or suppresses a negative delta.
From the repository root:
python -m randomness_lab.r1 \
--tasks 500 \
--trials 30 \
--swarm-size 5 \
--seed 42 \
--output results/r1.json
For a lighter run that keeps trial metrics but omits per-task records:
python -m randomness_lab.r1 \
--tasks 500 \
--trials 30 \
--no-task-records \
--output results/r1-summary.json
This experiment is a mechanism test, not a benchmark result.
A synthetic result such as “structural diversity beats replication at correlation 0.25” means only that the implementation behaves as expected under those assumptions. It does not establish that real multi-model coding swarms have that correlation or quality distribution.
The next evidence step is to replace synthetic worker outcomes with adapters that replay or execute real bounded coding-task results while keeping the same result schema.
The assumption sweep, synthetic N-scaling curves, and conservative real-result replay adapter now exist. See R1 collective-capability scaling for the N = 1, 2, 5, 10 reference and the explicit issue #13 coverage ledger.
The remaining steps require evidence rather than more synthetic plumbing:
The project should not promote a swarm strategy into the Verified Swarm Runner solely because it performs well in this synthetic experiment.