EMNLP 2026 · Universiti Malaya

Between Multiple Choice and Open Response

Evaluating LLMs with option-free, deterministic scoring.

A benchmark score measures not only the model, but also the instrument used to evaluate it.

* Equal contribution · † Corresponding author

Fixed settingGPT-5 · MyCulture · aligned knowledge
03

CRQ

22.9

Open response + judge

Expressive answers, but the result can depend on who evaluates them.

02

CSRQ

56.8

Option-free + deterministic

Construct a canonical subset, ordering, or matching, then verify it exactly.

01

MCQ

88.1

Visible final options

Easy to score, but answer choices can turn recall into recognition.

Evaluation instrument changes

What looks like model competence can partly be a property of the test.

MCQs expose candidate answers. CRQs remove those candidates, but their scores depend on an evaluator. CSRQs examine whether these useful functions can be recomposed.

01MCQ

Multiple choice

Select from visible final answers.

  • Deterministic scoring
  • Recognition and elimination cues
  • Non-trivial chance success
02CSRQ

Constrained structured response

Construct a canonical structured answer.

  • No final-answer combinations
  • Deterministic exact verification
  • Auditable answer space
03CRQ

Constructed response

Generate an open natural-language response.

  • Option-free elicitation
  • Human or LLM adjudication
  • Judge-dependent scores

Construct the answer. Verify the structure.

CSRQs use familiar multi-select, ordering, and matching structures as canonical answer spaces for LLM evaluation, not as new human-test item archetypes.

Return every statement that satisfies the question.

Apakah kenyataan yang betul mengenai permainan Lansaran?

A · Dibina secara individu
B · Berukuran 8–30 kaki persegi
C · Menggunakan kayu Selangan Batu
D · Hanya untuk kanak-kanak
Canonical response
••••••••••

Canonicalize → compare with key → exact score

Strict score𝟙 [ canonicalize(prediction) = canonicalize(answer) ]No judge required

Meet MyCulture.

A Malaysia-centered benchmark in Bahasa Malaysia, built to hold cultural knowledge constant while changing how that knowledge is elicited and scored.

01Arts02Attire03Customary practices04Entertainment05Food06Religions
Open the full benchmark guide

The same knowledge produces different measured scores.

Across benchmark families and model scales, removing final-answer combinations changes performance, even when scoring remains deterministic.

−26.66

Average option-removal gap

Across MalayMMLU and CS-EN, models consistently score lower under CSRQ evaluation.

Interactive comparison
Original figure ↗
MalayMMLU average71.5 → 41.9−29.64 points
CS-EN average72.6 → 48.9−23.68 points
Selected modelGPT-5
MalayMMLU81.98MCQ→59.46CSRQ−22.52 points
CS-EN76.32MCQ→63.16CSRQ−13.16 points
MalayMMLU · MCQMalayMMLU · CSRQCS-EN · MCQCS-EN · CSRQ

Every bar shows its exact score. Hover, focus, or click a model to update the breakdown above; use the dataset controls to simplify the chart.

Option-removal sensitivity is observed across model families, including models above 100B parameters.
MyCulture · reading the gaps

A gap is not a model score.

Each bar shows how far one model's score moves when only the question format changes. It tells you how sensitive the score is to the format, not how capable the model is.

Interactive gap explorer
Original figure ↗
GPT-5
Gemini-2.5-Pro
GLM-4.6
Qwen3-235B-Thinking
MCQ − CSRQ strictCSRQ strict − CRQ strict

Toggle either gap to isolate option-removal sensitivity or the shift to judge-based scoring.

Change the judge. Change the score.

The same CRQ outputs were evaluated under the same rubric by different LLM judges. Pairwise ranking agreement ranged from 0.40 to 1.00.

12.8percentage-point standard deviation for GPT-5 across judges
Interactive judge matrix
Original figure ↗
Highlight:
Evaluated model ↓ / Judge →
Qwen 235B
Qwen 30B
Gemini Lite
GPT-5 Nano
Std. dev.
12.80
12.72
11.96
6.53
12.88
Selected comparison42.45%

GPT-5 evaluated by Qwen3-30B Inst. This evaluated model varies by σ = 12.80 points across judges.

Hover, focus, or click a cell for context. Highlight a row to compare how judges score one model.

From knowledge point to auditable item.

The documented workflow converts suitable MCQ or CRQ items into CSRQs through knowledge acquisition, structured generation, and independent verification.

CSRQ benchmark conversion workflow from knowledge acquisition to question generation and verification
Only statements that pass format and source-supported verification are retained.
  1. 01
    Acquire

    Extract the factual, relational, or procedural knowledge point.

  2. 02
    Select

    Choose multi-select, ordering, or matching for the target knowledge.

  3. 03
    Generate

    Construct the question, statements, and canonical answer.

  4. 04
    Verify

    Check structure, answerability, and source-supported evidence.

Choose the instrument for the claim you need to support.

Use MCQ

For broad, low-cost screening and reproducible leaderboard comparison.

Use CRQ

When expressive responses are essential and reliable human or multi-judge adjudication is available.

What CSRQ does and does not claim.

01CSRQs do not prove genuine understanding or higher-order comprehension.

02They work best when an answer can be decomposed into valid response units.

03The answer space remains finite and does not fully replicate open generation.

04Construction adds costs for generation, distractor design, and verification.

Read, reproduce, and extend the work.

The paper, MyCulture dataset, and evaluation toolkit are available now.

BibTeX
@inproceedings{hew2026myculture,
  title={Between Multiple Choice and Open Response:
Evaluating LLMs with Option-Free Deterministic Scoring},
  author={Hew, Zhong Ken and Yang, Sze Jue and Chan, Chee Seng},
  booktitle={Proceedings of the 2026 Conference on Empirical Methods in Natural Language Processing},
  year={2026}
}