Getting on the map

NOBODY has yet called the police about Jerry Clough, but he gets strange looks. Strolling around Nottingham, he takes photographs seemingly at random, jotting notes and mumbling about missing numbers. Mr Clough is one of a handful of Britons who collect addresses for OpenStreetMap (OSM), a global group of volunteer cartographers who maintain free online maps. “Yes, it is a bit obsessive,” he says. “But it makes our maps much better.”

Addresses have always been important in the real world: among other things, they help establish people’s identities and guide emergency services to where they need to be. They increasingly matter in the virtual world, too, as websites and apps rely on them to give directions, send users to the nearest cinema or cheapest petrol station, and more. An accurate and detailed address book that includes geographical co-ordinates is turning out to be the connection that binds the digital and physical realms together.

Some countries have decided that addresses are such an important part of their social and economic infrastructure that publishing and updating them is best done by a single, central body—and that access should be free, without conditions. Denmark has moved farther in this direction than most. Though it has long had a standardised system for creating addresses, until 2001 several government agencies and private firms kept separate, inconsistent registries. “Addresses were treated as a mere add-on to other data,” says Morten Lind of the urban-affairs ministry.

Now Mr Lind’s ministry holds a unified national registry. It is updated daily with data from municipalities, which are responsible for allocating addresses, and is what geeks call “open”: anyone can download it without paying or being bound by licensing terms. A study in 2010 found that maintaining it had cost a mere €2m ($2.7m) in the previous five years—for financial benefits 30 times that amount to the 1,200 firms and other entities known to have used the data. Norway and the Netherlands have implemented similar schemes.

Denmark’s government compensated municipalities, which used to make money selling address lists. Elsewhere, an unwillingness to buy off the losers means progress has been slower. After years of deliberation, Britain at last has an official address register, the National Address Gazetteer. But it is owned by GeoPlace, a partnership between central and local governments that makes money by selling the data. And one of its main sources, the postcode-address file, was bundled in with the national postal service, Royal Mail, when a 60% stake was sold earlier this year, meaning that it is private property—even though the government has made much of the importance of open data.

That drew wide criticism. But it may make Britain the venue of a unique experiment. In what looks like damage limitation, the Cabinet Office has paid the Open Data Institute, a not-for-profit organisation, to build an open alternative. Starting from scratch would be too slow, so it is searching for address databases that it can use, which will be merged and tidied up to remove dud or duplicate entries. Volunteers must be recruited to resolve inconsistencies and fill in the blanks. And a business model must be found: its £28,000 ($46,000) grant will not last long. A first version should be ready by March, says Jeni Tennison, the institute’s technical director.

Less ambitious projects elsewhere show both how difficult all this will be—but also that it seems possible. In America OpenAddresses.io has got little further than creating a list of available address files; many counties have not been able to afford to digitise theirs. Ian Dees, one of the group’s founders, hopes to find the time and money to tour the country to collect paper files and scan them in.

In France, by contrast, the National Open Address Base (BANO), an open-address project, has merged information from local cadastres (registers) with data from OSM volunteers and other sources to create a file with more than 15m addresses, about 80% of the national total. Christian Quest, who launched the project, doubts addresses are sufficiently exciting to attract enough volunteers to keep it up to date, but hopes to get firms and government agencies to share their data.

Concerns about privacy may also slow the creation of open-address registries. In Germany, for instance, it is not clear whether physical addresses and geographical co-ordinates count as personal data, even if no name is linked to them. Some certainly think so; in former East Germany suspicious souls threw bricks at an OSM volunteer collecting addresses (they missed). And fire departments and other highly error-sensitive users may be slow to rely on unofficial sources for addresses, not least for fear of getting sued. But such registries may end up being more accurate, since errors are more likely to be spotted and fixed, and they are easier to keep up to date.

“Maintaining key registries centrally is clearly more efficient,” says Marc de Vries of TheGreenland.eu, a consultancy that has helped the Dutch government develop a range of registries, from topographical maps to vehicle registrations. “And once the data are in one place you want them to be used as much as possible, both inside the government and outside.”

Governments need to move quickly if they want to stay in the game. In many countries Google Maps is more complete and reliable than official sources. Mr Clough, for his part, will continue to gather addresses, no matter what. “I’m not particularly interested in addresses themselves,” he says. “But by collecting them I learn so much about my city.”