Articles
How name, address and phone data really works across countries — registries, exceptions and the mistakes we made.
58 articles
- How Migration Plants Surnames: The Data Trail of a Name Arriving in a New CountryIn France, the surname Traoré was carried by roughly 0.10 people for every 100,000 born in the 1940s. Among people born in the 1990s, that rate is 35.76 — a 358-fold increase across five birth decades…Read →
- How Our Person Generator Actually Works — And What It Still Gets WrongMost fake-name generators are one function: pick a name from a list, pick a city from another list, glue them together. Ours is not much more than that either — but the difference between "not much mo…Read →
- How Spain's Surname Registry Accidentally Measures IntegrationSpain's national statistics institute publishes a surname frequency table. It is a mundane object: a rank, a surname, and how many people carry it. Every country with a civil registry publishes someth…Read →
- How to Audit a Name-Frequency DatasetEvery weighted name dataset makes a claim about a country, whether or not its authors realise it. Somewhere in the file, one surname is the most common and one is the rarest, and the ratio between the…Read →
- Iceland's 59 Surnames That Are Not Supposed to ExistIceland banned surnames in 1925. The relevant sentence in the law is one line long and admits of no argument: "Ættarnafn má enginn taka sér hér eftir" — no one may henceforth take a family name. It ha…Read →
- Is Your "National" Dataset Actually Regional? A Five-Minute TestOur given-name data for the United Kingdom was built from British sources, labelled British, validated as British, and shipped as British. It was Scottish. Not partly Scottish, not Scottish-flavoured:…Read →
- Krzysztof Peaked in 1971. Kacper Peaked in 2001. How Birth Cohorts Separate Migrants From Their ChildrenIn Norway's name data, Krzysztof rises from zero to 1,148 people in the 1971 birth cohort — and then collapses to 14 by the 2001 cohort. Kacper, also Polish, does the exact opposite: 0 in every cohort…Read →
- One French Boy in Ten Was Called Jean. Today's Number One Gets 1.96%. The Collapse of Name ConcentrationAmong French boys born in the 1940s, 10.22% were named Jean. One in ten. The ten commonest boys' names covered 46.79% of the entire cohort — you could name half the boys in France from a list of twelv…Read →
- Phone Numbers That Are Too RegularWe have written before about fake phone numbers that cannot exist(fake-phone-numbers-that-cannot-exist.md) — numbers whose central office code began with a digit the numbering plan forbids, roughly on…Read →
- Postal Codes of the World: Why a Universal Address Generator Cannot ExistThere is a function in almost every test-data library that looks like this: It is wrong in 42 of the 64 locales we ship. Not "slightly unidiomatic" — structurally wrong, in the sense that the string i…Read →
- Regional Name Crowns: The First Names That Rule One Country and Vanish at the BorderThere is a myth that popular names are basically global — that the same handful of Emmas and Noahs rule everywhere. They do not. Cross a border and the crown often changes hands completely, and in som…Read →
- Rooted or Imported? Telling Them Apart With Nothing but the RegistrySpain's national statistics institute, INE, publishes its surnames without accents. GARCIA, MARTINEZ, TRAORE, CALDERON — 86,512 rows, 1,832 of them carrying Ñ, and zero carrying an acute accent or a d…Read →