JamC-QA

What is JamC-QA?

JamC-QA is a benchmark test that measures how well Japanese Large Language Models understand Japan’s culture, history, and geography. It stands for “Japanese Multiple Choice Question Answering,” comprising over 2,300 multiple-choice questions (four-option questions).

This test covers eight domains: Japanese culture, social customs, regional knowledge, geography, history, politics, law, and medicine. It’s designed to fairly evaluate the capabilities of Japanese language LLMs.

In a nutshell: A test sheet that grades Japanese AI on “how much it knows about Japan.”

Key points:

• What it does: Evaluates the knowledge of Japanese language LLMs with a test dataset
• Why it’s needed: Standard tests don’t cover Japan-specific knowledge
• Target audience: AI companies, language model researchers, companies deploying AI in Japan

Why it matters

Historically, Large Language Models like ChatGPT were evaluated primarily using “MMLU,” an English-based test. However, this test contains almost no Japan-specific knowledge.

Companies creating AI services for Japanese markets need to know precisely “This LLM is excellent in English, but what about Japanese culture?” JamC-QA makes this possible. Simultaneously, researchers aiming to improve language models use JamC-QA results as a crucial indicator for identifying improvement areas.

Test structure

JamC-QA provides several hundred questions each in these eight domains:

Culture (640 questions) Knowledge about movies, literature, music, art. Examples: “What is the dialogue from this movie?”

Customs (200 questions) Japanese social customs, etiquette, festivals. Examples: “What is the correct explanation of Tanabata?”

Regionality (397 questions) Dialects, region-specific customs, regional character. Examples: “Which agricultural product is Hokkaido’s #1 producer?”

Geography (272 questions) Natural geography like mountains and rivers. Examples: “What is Japan’s highest mountain?” from basics to advanced.

History (343 questions) Japanese historical events, figures, periods. Requires historical accuracy.

Politics (110 questions) Political systems, policies, government roles. Tests understanding of Japan’s unique political systems.

Law (299 questions) Japanese legal systems and laws. Examples: “From what age is someone legally an adult under civil law?"—practical knowledge.

Medicine (48 questions) Japan’s medical system and terminology. Medical accuracy is important.

Evaluation method

Tests use “four-option questions” with only one correct answer. Scoring is based on whether you select the correct answer exactly—there’s no partial credit for “almost correct.”

When companies develop Japanese chatbots, generally 70-75% correct rates indicate a certain level of knowledge.

Leaderboard results and examples

The highest-performing model “sarashina2-70b” (as of 2024) achieved approximately 72% accuracy, showing “jagged intelligence” with medicine domain (92%) being strong while regional knowledge (67%) remains weak.

This gives LLM developers the insight that “medical terminology is abundant in training data, but region-specific knowledge is insufficient”—a hint for improvement.

Real-world usage

Model selection When companies deploy Japanese AI chatbots, they can compare multiple models using JamC-QA and select the optimal one.

Research and development Language model researchers identify weak domains with JamC-QA and improve them through additional learning or fine-tuning.

Trustworthiness evaluation Users learn “This AI is strong in history but weak in regional knowledge” and can use it appropriately.

Related terms

• Large Language Model (LLM) — The AI being evaluated by JamC-QA
• Language Model — AI specialized in text processing
• Benchmark — Standard tests measuring AI performance
• Fine-Tuning — Optimization to specialize models in specific domains
• Jagged Intelligence — Uneven model capability across domains

Frequently asked questions

Q: Are all Japanese models evaluated with JamC-QA? A: No. Many major models are evaluated, but smaller or proprietary models may not be tested.

Q: Can I view the test questions beforehand? A: Yes. JamC-QA is public on Hugging Face, and developers can view it beforehand.

Q: Does high JamC-QA score mean perfect Japanese? A: No. JamC-QA measures knowledge quantity, not natural conversation ability or nuanced understanding.