activity
20242026
most citedUnderstanding Likelihood Over-optimisation in Direct Alignment Algorithms

1 citations · 1 across the 8 of their papers we have counts for

collaborators

9 papers

cs.CL2026

Explicit Boundary Markers for Subword Vocabularies

Sander Land, Clara Meister

Subword tokenizers represent many common words twice in space-using writing systems, once with a leading space and once without. The two entries have separate embeddings in models,…

cs.CL2026

MinGram: A Minimalist Unigram Tokenizer with High Compression and Competitive Morphological Alignment

Sander Land

The Unigram tokenizer uses an elegant representation which makes it straightforward to edit vocabularies, but its training is comparatively heavy and complex. We introduce MinGram…

cs.CL2026

Auditing LLM Benchmarks with Item Response Theory

Sander Land, Daniel M. Bikel

LLM benchmark labels are frozen at release and silently propagated into downstream benchmarks, errors and all. We introduce an Item Response Theory-based indicator that surfaces li…

cs.CL2026

Shorthand for Thought: Compressing LLM Reasoning via Entropy-Guided Supertokens

Zhenyu Zhao, Sander Land, Daniel M. Bikel +1

Reasoning in Large Language Models incurs significant inference-time compute, yet the token-level information structure of reasoning traces remains underexplored. We observe that r…

cs.CL2025

Which Pieces Does Unigram Tokenization Really Need?

Sander Land, Yuval Pinter

The Unigram tokenization algorithm offers a probabilistic alternative to the greedy heuristics of Byte-Pair Encoding. Despite its theoretical elegance, its implementation in practi…

cs.CL2025

RewardBench 2: Advancing Reward Model Evaluation

Saumya Malik, Valentina Pyatkin, Sander Land +4

Reward models are used throughout the post-training of language models to capture nuanced signals from preference data and provide a training target for optimization across instruc…

cs.CL2025

Command A: An Enterprise-Ready Large Language Model

Team Cohere, :, Aakanksha +227

In this report we describe the development of Command A, a powerful large language model purpose-built to excel at real-world enterprise use cases. Command A is an agent-optimised…

cs.CL2024★ 1 cited

Understanding Likelihood Over-optimisation in Direct Alignment Algorithms

Zhengyan Shi, Sander Land, Acyr Locatelli +2

Direct Alignment Algorithms (DAAs), such as Direct Preference Optimisation (DPO) and Identity Preference Optimisation (IPO), have emerged as alternatives to online Reinforcement Le…

cs.CL2024

Fishing for Magikarp: Automatically Detecting Under-trained Tokens in Large Language Models

Sander Land, Max Bartolo

The disconnect between tokenizer creation and model training in language models allows for specific inputs, such as the infamous SolidGoldMagikarp token, to induce unwanted model b…