# Stolen Probability: A Structural Weakness of Neural Language Models

arXiv: https://arxiv.org/abs/2005.02433 · HTML: https://mlsanity.com/paper/2005.02433/

## Key facts

- Cited by 22 papers in the map (data through 14 Oct 2026).
- First posted on arXiv 5 May 2020.

## Built on by (most cited first, 22 of 22)

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- [Prompting a Pretrained Transformer Can Be a Universal Approximator](https://mlsanity.com/paper/2402.14753/) (2024)
- [Task-Adaptive Tokenization: Enhancing Long-Form Text Generation Efficacy in Mental Health and Beyond](https://mlsanity.com/paper/2310.05317/) (2023)
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- [Switching to Discriminative Image Captioning by Relieving a Bottleneck of Reinforcement Learning](https://mlsanity.com/paper/2212.03230/) (2022)
- [AxomiyaBERTa: A Phonologically-aware Transformer Model for Assamese](https://mlsanity.com/paper/2305.13641/) (2023)
- [Compression Hacking: A Supplementary Perspective on Informatics Properties of Language Models from Geometric Distortion](https://mlsanity.com/paper/2505.17793/) (2025)
- [Norm of Mean Contextualized Embeddings Determines their Variance](https://mlsanity.com/paper/2409.11253/) (2024)
- [Shape of Elephant: Study of Macro Properties of Word Embeddings Spaces](https://mlsanity.com/paper/2106.06964/) (2021)
- [LABO: Towards Learning Optimal Label Regularization via Bi-level Optimization](https://mlsanity.com/paper/2305.04971/) (2023)
- [Reconsidering Degeneration of Token Embeddings with Definitions for Encoder-based Pre-trained Language Models](https://mlsanity.com/paper/2408.01308/) (2024)
- [On the Tip of the Tongue: Why LLMs Hallucinate Answers They Can Decode](https://mlsanity.com/paper/2603.13911/) (2026)
- [The Geometry of Language Model Logits: Generic Structure and Learned Departures](https://mlsanity.com/paper/2610.18520/) (2026)

## Abstract (arXiv)

Neural Network Language Models (NNLMs) generate probability distributions by applying a softmax function to a distance metric formed by taking the dot product of a prediction vector with all word vectors in a high-dimensional embedding space. The dot-product distance metric forms part of the inductive bias of NNLMs. Although NNLMs optimize well with this inductive bias, we show that this results in a sub-optimal ordering of the embedding space that structurally impoverishes some words at the expense of others when assigning probability. We present numerical, theoretical and empirical analyses showing that words on the interior of the convex hull in the embedding space have their probability bounded by the probabilities of the words on the hull.
