About pokecoin

Methodology

From records to coins

Each source is read into records, one per physical coin, keeping the source's own words next to the normalized values. A page that bundles several coins becomes several records, and digital coins are left out.

Records are then matched source by source. A record is only compared with coins that show the same Pokémon or subjects. A different region, a year more than one apart, a different material, size, back or trademark mark, or a production coin against a prototype or error rules a match out. Agreement on dates, color, finish, pattern, size and product names adds to a score, and disagreement on color or finish lowers it. A record that scores high enough joins the best coin; any other record starts a new coin. A coin takes at most one record from each source.

Some records are matched by hand, for example to join two records of the same coin or to keep two similar coins apart.

Which value is shown

When sources disagree, a coin shows one value and keeps the others. Measured diameters come from sources that measured coins, and a measured diameter decides the size class. Japanese names come from Japanese sources and material from official product pages. Other labels come from the first source that has one, in this order: Bulbapedia, the collector checklists, Pokémon Coin Fan and pokeboon, official product pages, then Cardmarket. The first date is the earliest dated release in any source.

Discrepancies

Every open disagreement between the sources of one coin is recorded as a discrepancy of one of these kinds. When other evidence, such as an official product picture or a measurement, shows which value is wrong, the coin uses the confirmed value and the disagreement is removed.

Naming difference 272 in the census

Sources use different words for what is most likely the same thing, such as silver and white for the same foil, or two names for one holo pattern.

Possibly two versions 535 in the census

One source says holo or mirror, another says non-holo. The same design was often made in both finishes, so this may be two coins rather than a mistake.

Source error 23 in the census

A source contradicts itself or an official product page.

Unresolved 107 in the census

Sources disagree on color, size or material, or on the first date by more than 45 days.

Holo and non-holo

The same coin design can exist in a holo and a non-holo version. So when one source calls a coin holo or mirror and another calls it non-holo, pokecoin does not assume that one of them is wrong. The coin is marked as possibly two versions until someone checks a physical coin or a clear photo. Treating it as an error would quietly remove a real coin from the census.

Licensing

The census dataset is published under Creative Commons Attribution-NonCommercial-ShareAlike (CC BY-NC-SA), because it includes data derived from Bulbapedia, which is licensed CC BY-NC-SA 2.5. The other sources keep their own terms, listed in the sources table, and are credited on every coin they contribute to.

Coin photos belong to their photographers. They are shown to help identify coins and are not covered by the dataset license.

pokecoin is an unofficial, non-commercial fan project and is not affiliated with Nintendo, Creatures, GAME FREAK or The Pokémon Company.