Jul 2026· International Conference on the Theory of Information Retrieval· 0 citations· 53 references
Computer Science
TL;DR
This work demonstrates that PFNs, which are originally trained for classification, successfully outperform classification baselines on ranking data and introduces a novel sampling and inference scheme to obtain pairwise predictions from PFNs' native pointwise architecture, analogous to pairwise LTR.
Abstract
Learning to rank (LTR) traditionally requires large-scale training data to generalize effectively. In low-data domains where expert annotation is scarce, the performance of LTR methods degrades sharply. Foundation models have alleviated similar data dependencies in other domains via in-context learning, but a foundation model for ranking with tabular features has not been explored yet. We propose prior-data fitted networks (PFNs) as a strong method for ranking in low-data settings. First, we demonstrate that PFNs, which are originally trained for classification, successfully outperform classification baselines on ranking data. Next, we evaluate PFNs as rankers, showing that they surpass state-of-the-art tuned baselines in low-data regimes. We introduce a novel sampling and inference scheme to obtain pairwise predictions from PFNs' native pointwise architecture, analogous to pairwise LTR. To address the limited context window of the transformers underlying PFNs, we propose a dynamic support set selection strategy for queries that scales PFNs beyond random subsampling. Our experimental results show that PFNs are an effective foundation model for ranking that provides significant gains when data is limited.
We introduce RecPFN, a prior-fitted network that brings in-context learning to sequential recommendation. RecPFN is pretrained entirely on synthetic clickstream environments sampled from a broad structural causal prior, enabling it to amortize Bayesian-style inference from a small support set. At inference, a lightweight decoder-only transformer conditions on a handful of domain sequences and produces next-item predictions for queries in a single forward pass, without any weight updates. Across eight public benchmarks, RecPFN achives state-of-the-art zero-shot performance while remaining strongly competitive with supervised methods in low-compute and low-data regimes. It is deployment-efficient and robust to domain shift, outperforming strong zero-shot baselines that rely on large real-interaction corpora. RecPFN provides a practical path toward generalizable, data-efficient recommenders and opens avenues for richer priors, longer-context ICL, and multimodal extensions. Code for training and evaluation will be made publicly available by the conference date.
En-Zhi Tan, Jia-Xiang Lim, Bryan Lijie Chew et al.· Annual International ACM SIG...· 0 citations
A task-centric, retrieval-based perspective is offered for how TFMs generalize: it is believed that tabular in-context generalization is largely retrieval-based, and good models are those that learn to identify relevant examples in the provided context and aggregate them well.
Nour Shaheen, Junwei Ma, Alex Labach et al.· 1 citation
This tutorial presents a systematic overview of this emerging paradigm of tabular foundation models, which treats tables as a common representation that can capture information from tabular data, time series, and graphs within a shared learning framework.
Peng Cui, Xingxuan Zhang, Han-Jia Ye et al.· Proceedings of the 32nd ACM...· 0 citations
In document reranking, rerankers based on Large Language Models (LLMs) demonstrate superior performance but are constrained by high memory consumption and latency. To develop lightweight yet high-performance LLM-based pointwise rerankers through knowledge distillation, we identify two critical limitations: teachers often yield over-smoothed and inaccurate supervision on hard negative samples, thereby hindering the student's optimization; furthermore, traditional methods underutilize the relevance score differences between candidates, which are crucial for ranking tasks. To address these challenges, we propose CRED (Calibrated Relational Enhanced Distillation), which integrates Adaptive Teacher Calibration (ATC) to calibrate teacher predictions and amplify score margins, while employing Preference Relation Alignment (PRA) to align the distributional patterns of relevance score differences, enabling the student to capture precise ranking structures. To support this approach, we also construct FineDistill, a dataset of 1M samples providing fine-grained score supervision. We distill an 8B teacher into a 0.6B pointwise student. Extensive experiments on TREC and BEIR benchmarks show that our model outperforms leading baselines in both performance and generalization.
Qingran Yang, Wenxuan Zhang, Yuting Wang et al.· Annual International ACM SIG...· 0 citations
The performance of Large Language Models (LLMs) is fundamentally influenced by the distributional composition of multi-domain pre-training data. While manual heuristics were prevalent in early models, they increasingly fail to capture the intricate synergies between domains as data complexity grows. To overcome the issue, a dominant approach seeks to fit a proxy function mapping between domain weights and their corresponding validation losses, and then find the optimal domain weights to minimize validation losses. These methods rely on strong structural assumptions, such as rank invariance or scaling laws, which are often violated, resulting in non-negligible estimation bias. A promising approach is to directly optimize the weighting scheme from data. However, it suffers from unstable optimization trajectory and prohibitive computational overhead, limiting its potential to search better domain weights configurations. This paper presents a Bayesian domain weighting method to infer the weights from a Dirichlet distribution via introducing Gamma prior information learned from observations. Experimental results demonstrate that proposed method could achieve stable and efficient domain weights learning, and identifies optimal mixtures while consuming substantially less data than search-based function-fitting methods, revitalizing optimization-based domain weighting for large-scale applications.
Xiang Yuan, Kaiqing Lei, Zhenyu Jin et al.· 0 citations
Node ranking is a fundamental problem in graph information retrieval, measuring the relative importance of nodes and supporting a wide range of applications such as influence analysis, recommendation, and graph-based retrieval augmented generation. However, exact computation of graph-based ranking measures is often computationally prohibitive at scale. Existing GNN-based ranking methods provide scalable approximations, but they are typically tailored to individual ranking criteria and require retraining for each downstream task, which limits their transferability and efficiency. Recent graph pre-training approaches aim to enable knowledge transfer across tasks, yet their learning objectives are largely misaligned with node ranking, resulting in suboptimal adaptability to ranking-oriented applications. To address these limitations, we propose PreGress, the first ranking-native pre-training and prompting framework for supporting a wide range of node ranking tasks. PreGress performs multi-task pre-training using our carefully designed objectives, including degree centrality prediction and attribute reconstruction, to jointly capture structural and attribute information. To support heterogeneous ranking criteria, we design lightweight, task-specific prompt modules that adapt a frozen ranking backbone to downstream tasks without full retraining. Experiments on six public graphs and two real-world query-to-item benchmarks---Yelp2018 and MovieLens-100K---together with a controlled five-criterion graph-access study demonstrate strong ranking quality with low task-specific state overhead.
Lujie Ban, Jiasheng Shi, Yingli Zhou et al.· 0 citations