Research programme · Evaluation science

Beyond the Benchmark

Dynamic and distribution-based evaluation in NLP — from stochastic paraphrasing, to multidimensional robustness, to Measurement-as-Distribution.

This programme asks what we learn when evaluation is treated as a measurement process rather than a single fixed score. The work makes variation, uncertainty and robustness visible through controlled generation, perturbation and repeated evaluation.

Research arc

EACL 2026

PTEB

Towards Robust Text Embedding Evaluation via Stochastic Paraphrasing at Evaluation Time with LLMs.

Introduces stochastic paraphrasing at evaluation time and aggregates results across repeated runs.

ACL Anthology ↗

EMNLP 2026

HTEB

The Harder Text Embedding Benchmark: Beyond One-dimensional Static Robustness.

Tests robustness across Lexical/Stylistic, Length and Language axes using stochastic transformations.

arXiv ↗

EMNLP 2026 · Findings

Measurement-as-Distribution

The Benchmark Is Not the Construct: Toward Distribution-Based Evaluation in NLP.

Generalises the earlier work into a model- and task-agnostic evaluation protocol.

Method ↗

Selected publications

  1. 2026
    The Benchmark Is Not the Construct: Toward Distribution-Based Evaluation in NLP
    Haithem Afli · Manuel Frank · EMNLP 2026 · Findings
    Research summary ↗
  2. 2026
    The Harder Text Embedding Benchmark (HTEB): Beyond One-dimensional Static Robustness
    Manuel Frank · Haithem Afli · EMNLP 2026 · Main Conference
    Preprint ↗
  3. 2026
    PTEB: Towards Robust Text Embedding Evaluation via Stochastic Paraphrasing at Evaluation Time with LLMs
    Manuel Frank · Haithem Afli · EACL 2026 · Long Paper · pp. 2832–2851
    Paper ↗

Measurement-as-Distribution

The proposed protocol represents an evaluation as P = (C, G, Φ, E, R): construct specification, data generation, validated perturbation, repeated evaluation, and reporting.

Construct

Specify the capability and the claim the evaluation is intended to support.

Generate

Create evaluation evidence through a principled and reproducible process.

Perturb

Introduce validated variation while preserving the intended construct.

Evaluate

Repeat evaluation so uncertainty and variability become observable.

Report

Report distributions and stability alongside point estimates.

What the work examines

Score versus rank

A model can retain its relative ordering while its absolute score changes under valid perturbation.

Multiple robustness axes

Lexical/stylistic, length and language variation can produce partly decoupled robustness profiles.

Evaluation as evidence

When inputs and conditions vary, the distribution of measurements becomes part of the evidence.