Creativity evaluation · LLM-as-a-judge · Persian NLP

CLiN: an Objective Framework for Evaluating Creativity in Short Persian Literary Texts

Mohammad Reza Modarres1,2 Armin Tourajmehr2
Yadollah Yaghoobzadeh1,2 Mohammad Taher Pilehvar3
1 School of Electrical and Computer Engineering, College of Engineering, University of Tehran, Tehran, Iran
2 Tehran Institute for Advanced Studies, Khatam University, Iran
3 Cardiff University, United Kingdom
EMNLP 2026 Findings

Can increasingly sophisticated LLM judges reliably evaluate creativity? We systematically test that assumption and introduce a simple, interpretable alternative for three structured TTCT-derived dimensions.

Accepted to Findings of EMNLP 2026. The arXiv preprint is available now; the ACL Anthology link will be added when available.

Research question

How reliable are LLMs as judges of creativity?

Across zero-shot, few-shot, reference-based, ensemble, and multi-agent settings, LLM judgments remain prompt-sensitive and are weakest on highly subjective dimensions. This motivates an alternative for the more structured TTCT-derived dimensions.

Method

CLiN in one view

CLiN evaluates each TTCT-derived dimension separately with a dedicated, interpretable proxy. It does not collapse the dimensions into a single creativity score.

01 TTCT: Originality

Originality → Novelty

Originality reflects how uncommon or distinctive an idea is. CLiN captures this with a novelty score that combines global statistical rarity with topic-relative uniqueness.

Novelty = PPL × Diversity
PPL global rarity
Diversity topic-specific uniqueness
Normalized PPL × Diversity
ρ = 0.45
02 TTCT: Fluency

Fluency → Lexical Idea

Fluency reflects the production of multiple ideas. CLiN approximates idea count by clustering contextual token representations into semantically related groups.

semantic clusters of token embeddings
Contextual embeddings → DBSCAN
ρ = 0.46
03 TTCT: Elaboration

Elaboration → N-gram Diversity

Elaboration reflects the amount of detail used to develop an idea. CLiN uses lexical diversity as a simple proxy, counting unique content-bearing units.

text
unique content-bearing units
Unique content-bearing tokens
ρ = 0.67

Each card pairs the human-rated TTCT dimension with its corresponding CLiN proxy and visualizes the computation used by that proxy. Spearman correlations are computed against the corresponding human ratings across all 200 texts.

Findings

Simple proxies remain competitive with LLM judges

The experiments separate two questions: how well LLMs judge creativity, and whether transparent objective proxies can recover structured human judgments.

Prompt sensitivity
0.33

Correlation with the baseline can fall to ρ = 0.33 for fluency under paraphrased prompting, illustrating substantial sensitivity to formulation.

Subjective dimensions

LLM–human alignment is consistently weaker for emotion and attractiveness than for the structured TTCT-derived dimensions.

LLM-as-a-judge

Correlation with human ratings

Spearman correlation by model and evaluation dimension.

* denotes cells marked as not statistically significant in the paper.
Text source

Average LLM–human alignment

Structured dimensions are comparatively stable across human-authored and model-generated text, while holistic creativity and emotion decline on model-generated text.

DimensionHumanModel-generatedΔ
Originality0.3960.401+0.006
Fluency0.2960.364+0.069
Elaboration0.3470.333−0.014
Emotion0.1960.089−0.107
Creativity0.3390.196−0.143
Attractiveness0.0730.0730.000
Benchmark

200 short Persian literary texts

The study pairs human and model-generated literary text with multi-dimensional human ratings to evaluate both LLM judges and objective proxies.

Browse released data →
100human-authored
100model-generated
5Persian annotators
6rated dimensions
5 themeshope · despair · longing · love · friendship
Artifacts

Code and data are organized for inspection and reuse

The repository preserves the original research notebooks and score exports, with a cleaned directory structure and documentation for each component.

Abstract

About the paper

Evaluating creativity in large language model (LLM) outputs remains challenging because creativity is multidimensional and human-centered. We examine how reliably LLMs evaluate short literary text in Persian, a low-resource language, across multiple evaluation strategies and prompt formulations. We find that LLM–human agreement varies substantially across dimensions: alignment is stronger for structured TTCT-derived properties such as Originality, Fluency, and Elaboration, but considerably weaker for more subjective dimensions, particularly Emotion and Attractiveness. Judgments are also sensitive to prompt formulation, while few-shot prompting, ensembling, and multi-agent debate provide no consistent improvement. Motivated by this dimension-dependent behavior, we investigate whether structured creativity dimensions can instead be approximated using simple, interpretable proxy metrics. We introduce CLIN, which evaluates three TTCT-derived dimensions separately using topic-aware novelty for Originality, contextual lexical clustering for Fluency, and lexical diversity for Elaboration. These proxies achieve human alignment comparable to or better than the strongest zero-shot LLM judge in our setting while requiring substantially lower evaluation cost.

Publication Findings of EMNLP 2026 Read the arXiv preprint. The ACL Anthology link will be added when available.