Japanese AI firm releases open construction cost dataset

By AI, Created 6:58 AM UTC, May 18, 2026, /AGP/ – The Horizons Co. released 20 verified construction cost diagnoses as an open dataset, showing overcharges as high as ¥2.8 million and a fraud rate of 84.9% in one case. The company says the release is meant to make contractor pricing more transparent and easier to scrutinize.

Why it matters: - The dataset gives homeowners and industry observers a way to compare contractor estimates against documented diagnoses. - The largest overcharge found was ¥2.8 million, or about $19,600, which underscores how wide price gaps can run in consumer construction work. - The release is designed to support independent review of the company’s diagnostic method through open data and audit hashes.

What happened: - The Horizons Co. released 20 verified construction cost diagnosis cases as an open dataset under CC-BY 4.0. - The release includes bilingual Japanese and English reference pages. - The dataset comes from real diagnoses performed by the company’s AI-assisted HORIZON SHIELD service. - The company said the release was made public on May 18, 2026, from Hiratsuka, Kanagawa, Japan.

The details: - The 20-case dataset spans 15 prefectures in Japan and 20 construction categories. - Average overcharge detected across the cases was ¥825,000, or about $5,775. - The highest detected fraud rate was 84.9% in a termite extermination case in Chiba Prefecture. - In that case, the quoted price was ¥1,850,000 and the fair price was ¥280,000. - The maximum overcharge was a ¥2,800,000 pre-handover “specification change” surcharge in a new construction case. - Covered work includes exterior painting, roof repair, water systems, termite extermination, seismic reinforcement, solar installation, demolition and office restoration, plus 12 other categories. - Each case includes a 12-character cryptographic audit hash derived from the canonical input fingerprint. - The dataset is published in human-readable HTML and machine-readable JSON. - The release also ties back to the company’s Pre-Transaction Knowledge Anchoring Protocol Declaration, which was anchored to Bitcoin Block #949356 on May 14, 2026, via OpenTimestamps. - The declaration was hashed with SHA-256 to 596da30ba4ca731f21efaa1c4a6537290e996e0f039cbe57704de1674e4a0282. - The underlying research appears in the Japan Construction Cost Database v1.2.2, available on Zenodo and engrXiv under open-access terms. - HORIZON SHIELD is available at the company’s web app, with the dataset pages at English, Japanese and GitHub.

Between the lines: - The release blends product marketing, open-data publishing and research validation into a single launch. - Anchoring the declaration to a Bitcoin block is meant to make the document timestamped and independently checkable. - The company’s emphasis on audit hashes and public datasets signals a push for credibility in a market where contractor estimates are often hard for customers to verify. - Toshikatsu Oga, the company’s representative director, said the goal is to invite independent scrutiny of the methodology and outcomes.

What’s next: - The company says per-diagnostic anchoring is under separate development. - HORIZON SHIELD also offers a construction cost review for ¥55,000, a change-order assessment for ¥33,000, an on-site completion inspection for ¥88,000 and a ¥5,500 reverse-estimate PDF report. - The Horizons Co. says it will direct part of HORIZON SHIELD revenue to Médecins Sans Frontières as part of its mission to reduce information asymmetry in construction markets. - The company says it has voluntarily aligned the system with Article 12 record-keeping and Article 14 human-oversight principles in the EU AI Act, while not claiming the system is high-risk under Annex III.

The bottom line: - The Horizons Co. is trying to turn construction cost checking into a verifiable, open-data workflow, with unusually detailed case records and cryptographic provenance attached to each example.