Harpd Answers · Explained
What is the Harpd evidence register?
The evidence register is the public list of every claim Harpd publishes, each resolved to its source dataset, methodology, data date and confidence. It is what makes a Harpd number auditable rather than merely stated.
Quick answer
What is the Harpd evidence register?
The Harpd evidence register is the public record of claims. Every important factual statement Harpd publishes appears with the dataset it came from, the methodology that produced it, the data date, its claim type (measured, observed, calculated, modeled or editorial) and its verification status. It is published as a page at /evidence/ and as data at /data/evidence.json.
- Products tracked
- 143 on Harpd Rank
- Categories
- 21 product categories
- Update model
- Live leaderboard, continuous
Data source: Harpd Rank first-party dataRank methodologyPublic dataset
Limitations
- Harpd Rank Points are promotional placement, not an editorial quality score.
- Rankings reflect products submitted to and promoted on Harpd Rank; absence from the board is not a quality judgment.
Data source: Harpd Rank first-party data
How it works
The mechanics, plainly
Each claim is registered once with a stable id, then referenced by the pages that use it. The register is built from the same datasets the pages read, so a claim cannot describe a number the site no longer publishes. Claims that fail their evidence check are blocked rather than published — the register records the block, not just the pass.
How it compares
Harpd vs the traditional approach
| Aspect | Harpd / this model | Traditional |
|---|---|---|
| Purpose | Prove where each number came from | Cite a source in prose |
| Granularity | One entry per claim, with a stable id | One citation per article |
| Machine access | JSON at /data/evidence.json and /data/claims.json | Not machine-readable |
| Failure handling | Unsupported claims are blocked and reported | Silently dropped |
Why it matters
Anyone can publish a number. What makes a number citable is being able to check it. The evidence register turns "Harpd says" into "Harpd says, and here is the dataset, the method and the date" — which is the only version of the claim worth quoting.
Frequently asked questions
How do I check a specific Harpd number?
Look it up in the claim registry at /citations/ by claim id, or read /data/claims.json. Each entry names the dataset, the methodology URL, the data date and the confidence.
What does "blocked" mean in the register?
A blocked claim is one that failed its evidence check and was therefore not published. The register records the failure so the gap is visible rather than hidden.
Does the register cover every sentence on Harpd?
No — it covers factual claims. Explanatory and methodological prose is governed by the methodology pages, and product descriptions are maker-supplied content rather than Harpd claims.