ML: Retrieval

Machine-learning ideas tagged Retrieval in the ML taxonomy of the Math2NN corpus.

32 ideas found

△ Mechanism confirmed, baseline not beaten 2026

Seed-Anchored Budgeted Graph Context

Replace arbitrary graph serialization or global top-k retrieval with deterministic locality tiers centered on entities matched by the question. Render every candidate unit in the highest-priority seed-local tiers before admitting more distant or weakly connected material, and use stable identifiers to make ties reproducible. If the complete seed-local candidate region fits within the context budget, no relevant unit in that region is lost to truncation.

Useful8/10
Difficulty4/10
Novelty7/10
Paper: Seed-Anchored Budget-Bounded Graph Rendering for Question Answering on Industry-Standard Power-Grid Information and Exchange Models arXiv:2609.02011
△ Mechanism confirmed, baseline not beaten 2026

Hadamard-CLIP joint interaction head

Replace the usual sum of pairwise modality similarities with a higher-order score based on the coordinatewise Hadamard product of all normalized modality embeddings. For modalities indexed by i=1,...,m, score a tuple using s(x_1,...,x_m)=\omega^\top(\bar g_1(x_1)\odot\cdots\odot\bar g_m(x_m)), where \omega is learned and \odot is coordinatewise multiplication. This adds explicit m-way interactions without concatenating raw features or introducing a joint encoder.

Useful8/10
Difficulty4/10
Novelty7/10
Paper: Expressivity In Multimodal Contrastive Learning arXiv:2608.17203
✗ Mechanism failed 2026

Barycentric One-to-Many Alignment

Replace pointwise cross-modal or prototype-to-instance matching with a loss that compares source pairwise inner products to inner products between target conditional means. A source prototype can align to a cloud of target instances while preserving its semantic barycenter, instead of being forced to match every target instance individually.

Useful8/10
Difficulty5/10
Novelty6/10
Paper: Barycentric Weak Inner-Product Gromov-Wasserstein arXiv:2608.25145
△ Mechanism confirmed, baseline not beaten 2026

Implicit Higher-Order TPR Memory

Support conjunction queries over multiple roles without explicitly storing a huge tensor of repeated objects. Represent the required higher-order memory through query-dependent contractions, enabling compositional retrieval with memory that scales linearly in the number of objects.

Useful7/10
Difficulty6/10
Novelty7/10
Paper: TPR-Attention for Combinatorial Generalization arXiv:2608.30124
✗ Mechanism failed 2026

Pisot-Orbit Deterministic JL Layer

Replace a dense random projection used before retrieval, classification, or expert routing with a publicly reproducible matrix generated by a Pisot beta-transformation orbit. Search over a small public seed and sampling gap to select one matrix that preserves the calibration set's pairwise distances, then freeze it for training and inference. The projection removes random-matrix storage and makes the same embedding transform exactly reproducible across servers or proof systems.

Useful7/10
Difficulty5/10
Novelty7/10
Paper: Deterministic Johnson--Lindenstrauss Projections from Pisot $β$-Transformations for Zero-Knowledge Private Routing arXiv:2608.13078
✗ Failed on benchmark 2026

Information-Gated Attention

Use predicted covariance reduction as a differentiable gate for selecting tokens, views, sensors, or retrieved demonstrations. The gate favors inputs with high expected information gain while accounting for acquisition cost, turning attention and data collection into active observability optimization.

Useful7/10
Difficulty5/10
Novelty7/10
Paper: Information-Aware Model Predictive Control for Satellite Inspection arXiv:2608.07765
△ Mechanism confirmed, baseline not beaten 2026

Spectral Burn-In and Retrieval Switch

Use the observer contraction rate as an online inference controller. Run the latent observer when its estimated contraction is strong, and invoke expensive retrieval or latent-state reinitialization only when contraction is weak or observation residuals indicate model mismatch.

Useful7/10
Difficulty5/10
Novelty7/10
Paper: Contraction versus Recurrence: An Exponential Separation in Observation-Based Prediction of Deterministic Dynamics arXiv:2607.14885
Unverified 2026

Low-Rank Gromov-Wasserstein Cross-Attention

Replace ordinary feature-only cross-attention between two graph sets with a transport coupling optimized using pairwise structural costs. Use the paper's positive-semidefinite graph-kernel factorization to compute the quadratic GW interaction without materializing an O(N_0^2 N_1^2) tensor, and use the inexact-gradient convergence bound to control truncated or approximate updates. The resulting coupling can be used directly as attention weights or as a soft graph-matching matrix.

Useful6/10
Difficulty6/10
Novelty6/10
Paper: Discrete Gromov-Wasserstein Duality: Algorithms and Isomorphism Testing arXiv:2609.03094
Unverified 2026

GP-DPP Adaptive Token Selection

Replace fixed-budget token or patch pruning with greedy selection that combines a teacher-derived relevance score and Gaussian-process mutual information. Select an item when it is both relevant and non-redundant, and stop when the largest remaining information gain falls below a calibrated threshold instead of retaining a fixed number of items.

Useful6/10
Difficulty5/10
Novelty5/10
Paper: InfoDPP-PAC: Principled Patch Selection for Whole Slide Image Analysis arXiv:2608.23574
Unverified 2026

Leaf-Relocation Tree Router

Learn a branching hierarchy for tokens, examples, or experts by greedily relocating leaves to reduce T-Robinson violations. The resulting tree supplies hierarchical candidate sets for retrieval or MoE routing, allowing the model to search a small subtree instead of all items while adapting the hierarchy to learned representations.

Useful6/10
Difficulty6/10
Novelty7/10
Paper: T-Robinson Spaces: Structure, Recognition, and Applications to Real Data arXiv:2608.21248
Unverified 2026

Calibration-validated uncertainty-aware sparse routing

Replace a single plug-in top-k router decision with a confidence correspondence containing every router parameter candidate and sparse expert assignment that remains compatible with calibration and the current input. Project this set onto a hierarchy of expert groups and return the finest group-level decision supported by all surviving explanations; otherwise coarsen the route or abstain. Active endpoint bracketing evaluates only candidates that could still change the projected routing report.

Useful6/10
Difficulty6/10
Novelty7/10
Paper: Physical-Support Confidence Sets for Highly Coherent Dictionaries arXiv:2608.20295
Unverified 2026

Hardy–Szegő Repulsive Token Router

Replace independent top-k token selection by a quality-weighted determinantal subset objective based on the Hardy–Szegő kernel. Tokens with high learned quality are preferred, but geometrically redundant tokens have a small determinant contribution, encouraging diverse sets of routed experts, retrieved items, or attended context tokens.

Useful6/10
Difficulty6/10
Novelty5/10
Paper: Hardy-Szegő Point Processes: Large Deviations and Strong Szegő Asymptotics arXiv:2608.17509
Unverified 2026

Levin-Bit Prompt Scoring

Rank candidate prompts, demonstrations, critiques, or system instructions by how many bits of reproduction cost they save for a specified artifact distribution. Replace raw prompt-token heuristics with a paired score that rewards both higher success probability and lower generation computation, then train or retrieve prompts maximizing this score under a token budget.

Useful6/10
Difficulty5/10
Novelty6/10
Paper: The Value of a Prompt: An LLM-Relative Kolmogorov-Complexity Approach arXiv:2608.16438
Unverified 2026

Synchronized spherical dimension bridge

Insert a hyperspherical adapter that splits an embedding into several unit-sphere blocks, changes the dimension of each block, and recombines them with a synchronized spherical join. Train the adapter to preserve pairwise angular distances, while using the paper's max-distortion composition principle to avoid uncontrolled accumulation of blockwise errors.

Useful6/10
Difficulty5/10
Novelty7/10
Paper: The Gromov-Hausdorff Distance Between Consecutive Spheres arXiv:2608.13264
Unverified 2026

Wasserstein-Gated Cached Equilibrium Adapter

Add a small constrained equilibrium layer whose response depends on the current neural state and recent exogenous history, then cache responses keyed by a learned history embedding. For a new history, reuse a cached response only when an empirical Wasserstein distance to the cached history is below a threshold; otherwise run a few inner optimization iterations. The paper's local Holder and trajectory-stability results motivate graceful degradation rather than catastrophic errors for nearby…

Useful6/10
Difficulty5/10
Novelty6/10
Paper: Stability of Differential Stochastic Variational Inequalities with History-Dependent Responses and Transfer Learning arXiv:2608.06923
Unverified 2026

Random Half-Space Geometry Layer

Represent each Euclidean input point by its responses to randomly sampled half-spaces, then center those responses by the minibatch or source-distribution half-space occupancy. Use squared distances between these representations as a geometry-preserving substitute for raw Euclidean distances in graph-NN edge construction, cross-domain retrieval, or geometry-aware attention. The layer can compare point clouds from different ambient dimensions because each domain has its own half-space dictionary…

Useful6/10
Difficulty4/10
Novelty6/10
Paper: Sample Complexity for the 2-Gromov-Wasserstein Distance arXiv:2607.27514
Unverified 2026

Continuous Edge Prototypes

Replace node-restricted graph prototypes by centers that may lie at arbitrary coordinates on graph edges. For each prototype, hold its assigned points and shortest-path branches fixed, then update its edge coordinate by an exact clipped weighted least-squares formula; recompute branch changes only at arc bottleneck points. This creates a graph-aware vector-quantization or retrieval module that can represent semantic locations between existing nodes.

Useful6/10
Difficulty5/10
Novelty6/10
Paper: A Foundational Perspective for Partitional Clustering on Networks arXiv:2607.25144
Unverified 2026

Closed-Form DynaBase Calibration

Calibrate the two blend coefficients directly from a context trajectory rather than using gradient descent. The one-step prediction problem is a two-variable ridge regression, making per-task adaptation nearly free and suitable for zero-shot or few-shot system identification.

Useful6/10
Difficulty2/10
Novelty6/10
Paper: A Minimal Interpretable Architecture for Zero-Shot Reconstruction of Dynamical Systems arXiv:2607.14937
Unverified 2026

DynaBase Retrieval Forecast Head

Replace a parameter-heavy recurrent transition, or use this as a fallback, with a two-parameter nearest-neighbor successor blend in latent space. Given a query latent state, retrieve the closest state from an in-context trajectory and combine the query, the retrieved state, and its observed successor; this gives a zero-shot dynamical forecast with almost no trainable transition parameters.

Useful6/10
Difficulty4/10
Novelty5/10
Paper: A Minimal Interpretable Architecture for Zero-Shot Reconstruction of Dynamical Systems arXiv:2607.14937
Unverified 2026

Capacity-aware compressive-plus-indexed memory

Replace a purely recurrent or state-space history summary with two explicitly separated paths: a fixed-size state channel for compressed sequence mixing and a query-dependent indexed channel for exact or near-exact retrieval. Train a lightweight gate to invoke top-k retrieval only when the recurrent state has insufficient evidence for the current query, preserving near-constant cost on ordinary tokens while preventing catastrophic failures on long-range exact-recall tasks.

Useful6/10
Difficulty5/10
Novelty4/10
Paper: The Capability Convergence Hypothesis: Capability from Access Structure, Not Scale arXiv:2607.14144
Unverified 2026

Positive-Cycle Matching Repair

Use the paper's cycle-gain criterion to repair an approximate bipartite matching produced by greedy matching, truncated Sinkhorn, or a neural router. A directed edge from matched red item i to red item j represents replacing i's current blue partner with j's partner; any positive-gain directed cycle is a guaranteed improving, feasibility-preserving reassignment.

Useful6/10
Difficulty5/10
Novelty6/10
Paper: Characterization and equilibrium of bichromatic max-sum matchings arXiv:2607.10070
✓✓ Beats tuned baseline 2026

Epoch-Frozen Masked Low-Rank Candidate Encoder

Add an online low-rank reconstruction layer before a recommender or ranking MLP. It estimates a latent action-feature subspace from masked candidate vectors, freezes that subspace for an epoch, reconstructs each partially observed candidate in the latent coordinates, and feeds only those coordinates to the predictor. The method is most promising when the ambient candidate dimension d is large but the effective rank m is small and missingness is not too severe.

Useful6/10
Difficulty5/10
Novelty7/10
Paper: Stochastic Linear Bandits with Partially Observed Actions arXiv:2607.08971
✗ Failed on benchmark 2026

Wide-tree invariant alignment layer

Replace a purely pairwise embedding similarity used for set alignment with a sum of rooted-tree contraction scores. Each tree feature aggregates products of several coordinate-level interactions and can preserve correspondence information under an unknown orthogonal transformation, allowing matching from moderate correlation rather than nearly identical embeddings. Use the resulting score matrix for Hungarian matching, contrastive loss, or a differentiable Sinkhorn assignment.

Useful6/10
Difficulty6/10
Novelty7/10
Paper: High-Dimensional Procrustes Matching via Tree Counts arXiv:2607.08538
✗ Mechanism failed 2026

Expander OMP Sparse Inference

Use the expander decoder as a structured sparse-coding dictionary and replace dense OMP correlation steps with edge-wise gather-and-reduce operations. This is useful when codes must be inferred iteratively, including interpretable feature extraction, sparse retrieval, or an inference-time latent selector that cannot rely entirely on an amortized encoder.

Useful6/10
Difficulty4/10
Novelty6/10
Paper: Expander Sparse Autoencoders: Parameter-Efficient Dictionaries for Mechanistic Interpretability arXiv:2607.01799