AIMech AI

Adaptation sampling

Algorithms AIMech:AdaptationSampling DRAFT
An online optimizer-hyperparameter controller that compares sample quality under a current and a hypothetical setting, using either fresh evaluations or importance-weighted reuse of existing observations, to decide how to adapt the setting.
Identity Notes & Concept Scope Adaptation sampling denotes the online optimizer-hyperparameter comparison controller, with direct fresh-sample and virtual density-ratio-reuse modes. It differs from baseNES/xNES/SNES/IGO updates, CMAevolutionpaths, Rpropgradient-sign control and population-based training. xNES-as is the composed optimizer, not an alias. Current733native442AIO inventory and four ignored-inclusive checkout scans found no equivalent identity; preserve existingowner195. Current committed331 assessment covers733native and442pinnedAIO records: all1175 identity/definition/hash rows equal the accepted natural-gradient research inventory. Four combined rg --no-ignore --hidden scans reconcile4491occurrences in196unique line contents. Earlier supporting assessments cover167 retained contents; root read all29 newly observed contents, including new331 generated pages/review and hyphenated adaptation-sampling exclusions. The initial oversized display was recovered with a bounded read of items13–20. All new contexts describe established NES/IGO/xNES/SNES or reserve the proposed methods; none supplies an equivalent maintained record. All908main393nested frontier objects retain the331 predecessor; root reassesses owners193–196/203 and retained broader supporting semantic/frontier/AIO readings. Original natural-gradient2997match and adaptation1456match assessments remain separately attributed, not claimed as fresh full root reread. Actual merge/base and prewrite searches must be verified before creation; no universal absence or saturation.

Claims & Grounded Evidence

6 Claims
Mechanism #direct-hyperparameter-comparison
Given an algorithm setting theta, a sampling law pi_theta and a quality measure psi for its samples, direct adaptation sampling evaluates fresh samples under a nearby hypothetical setting theta_prime. It retains the new setting when the chosen quality comparison indicates sufficient improvement and otherwise reverts. The comparison acts at the algorithm-hyperparameter level, with progress over time as its motivation; it is not itself the base optimizer’s natural-gradient update. The source gives a Mann–Whitney comparison as an example, not a complete universal testing protocol.
Mechanism #virtual-density-ratio-reuse
Virtual adaptation sampling reuses samples z_i drawn under pi_theta. It compares their existing quality values once with unit weights and once with weights w_i_prime = pi_theta_prime(z_i) / pi_theta(z_i). The weights represent the hypothetical law while the observed quality values remain unchanged. This can avoid fresh quality evaluations for the comparison, but the two groups reuse the same observations and are not independent samples.
Mechanism #reported-weighted-rank-comparison
For quality values s_i and s_j_prime with positive weights w_i and w_j_prime, the thesis defines U as the sum of w_i*w_j_prime over pairs with s_i greater than s_j_prime, plus half that product for equal values. It sets m = sum_i w_i and m_prime = sum_j w_j_prime, then uses mu = m*m_prime/2 and variance m*m_prime*(m+m_prime+1)/12 in a normal comparison. These are the source’s reported weighted-statistic and approximation formulas. They do not establish nominal independent-sample calibration for the paired, importance-weighted virtual mode.
Mechanism #nes-counterfactual-scale-learning-rate
In the concrete NES application, the controller adapts the learning rate eta_sigma of the global search scale. It forms the hypothetical distribution that would result from the previous optimizer state using 1.5 times the current eta_sigma, then weights the current population by the hypothetical-to-actual density ratio and compares its fitness ranks with their weighted counterpart. The hypothetical learning-rate change is distinct from directly multiplying the current search scale by 1.5 or adapting every optimizer block learning rate.
Mechanism #empirical-increase-or-return-policy
The described NES policy starts from a conservative initial learning rate. When its improvement criterion succeeds, it sets eta_sigma_new = min((1+c_prime)*eta_sigma, 1); otherwise it sets eta_sigma_new = (1-c_prime)*eta_sigma + c_prime*eta_sigma_init. The reported defaults are c_prime = 0.1 and rho = 1/2 - 1/(3*(d+1)) for search dimension d. These are empirical controller settings, not optimality or nominal error-rate guarantees. The unspecified test-return and rank-orientation conventions in the displayed pseudocode remain explicit limitations.
Scope #modes-and-composition-boundary
The source distinguishes direct fresh-evaluation adaptation from virtual reuse and also discusses combining reweighted observations with some new hypothetical-law samples of weight one. Fresh sampling and reuse are therefore explicit modes, not interchangeable implementations. The 2012 paper calls the combination of xNES with the controller xNES-as. That combined optimizer, generic importance sampling, importance mixing and the weighted comparison statistic are not exact aliases of the adaptation-sampling controller.

⚠️ Curated Limitations & Negative Results

Artificial Intelligence Ontology (AIO) Grounding

Explicit AIO Snapshot Assessment: No Match

Rationale: No inspected pinned target supplies a sufficiently informative identity or necessary defining-component relation for the general comparison-based controller. Optional learning applications and host-optimizer components do not justify forcing a mapping.

Search Scope: Current733native442pinnedAIO inventory and all scoped synonyms were reconciled at committed331head32760a0e5b75bbc3187aa1ae2ed2ed71f499ae9f. Four combined ignored/hidden-inclusive scans yielded4491occurrences in196distinct contents; retained supporting readings cover167, with all29 new contexts read by root. Earlier adaptation-specific reading covered88definitions,nine full native neighbors,13exactAIOCLASSnodes and74incidentedges; root inspected all13nodes/74edges. All908main393nested frontier objects were mechanically scanned in retained research;95relevantlabels/five fullowners were read, and currentowners193–196/203 were reassessed. Existingowner195 remains the sole controller lead. This bounded pinned-snapshot assessment is not global absence or literature saturation; actual merge-based creation freshness is recorded separately.
Examined AIO Candidate Rejection Reason
AIO:MetaLearning The source uses meta-learning in a broad optimizer-control sense. The pinned target specifically concerns metadata about machine-learning experiments; that scope is not inherent to this general controller.
AIO:TrainingStrategy The pinned definition concerns model training and preprocessing. The controller can adapt black-box search without training a machine-learning model.
AIO:MathematicalFunction The pinned definition is broad and is not restricted to scalar functions. Generic computational describability supplies no sufficiently informative identity or necessary specific-component match for this family of sampling, comparison and controller procedures.
AIO:ExponentialFunction Scalar exponentiation is a component of a possible underlying NES update, not a mandatory defining operation of the general adaptation-sampling controller.
AIO:ReinforcementLearning A possible policy-search application does not make an environment/reward learning interface inherent to the controller.
AIO:ProbabilisticHiddenLayer Evaluating sampling densities does not supply a predictive category-estimation hidden layer.
AIO:SelectionAndSamplingBias Coverage and calibration problems are limitations of a comparison, not an identity mapping to a bias category.
AIO:ActiveLearning Extra objective or quality evaluations do not inherently constitute interactive labeling or a predictive query-selection task.
AIO:KnowledgeTransfer Reusing evaluations within a search is not inherently transfer of knowledge between entities. The target’s related Adaptation synonym does not establish equivalence.
AIO:MetaLearningLLM No language model, pretrained prior or few-shot task-adaptation mechanism is required.
AIO:EvolutionaryLLM No language model is required; the related evolutionary algorithms synonym does not identify this controller.
AIO:RegularizationLayer No layer-specific parameter or activity penalty is required.
AIO:MachineLearningTask The controller can operate on arbitrary black-box search. Adapting optimizer settings does not by itself identify the pinned task of building methods that learn from data.

Evidence Sources & Primary Literature

3 Sources
Source ID Publication / Document Type / Access Reference & Checksum
schaul2011-thesis
Tom Schaul
author technical report
full_text
sha256:788a40bc471c…
wierstra2014
Daan Wierstra, Tom Schaul, Tobias Glasmachers, Yi Sun, Jan Peters, Jürgen Schmidhuber
primary paper
full_text
sha256:80ec84951836…
schaul2012
Tom Schaul
primary paper
full_text
sha256:ef2d3e54ebf7…

Curation Provenance

Curator: Codex
Method: ai_assisted
Model: GPT-6
Created: 2026-10-15T05:26:04Z
Updated: 2026-10-15T05:26:04Z
Source File: data/curated/AdaptationSampling.yaml