Many surveys aim to register the residence of respondents. For face-to-face surveys this is no problem because the interviewer will register the residence. For web-surveys however the survey needs to ask where the respondent lives. Increasingly survey holders have developed a database with names of municipalities, cities, or regions, so that survey respondents only need to type a few characters and can then select from the matches in the database. Since 2008, the WageIndicator Foundation has developed a REGION database for this survey question. It uses a search tree, whereby respondents first identify their region, province, or county, and in a second step their residence within this province. The larger or more significant places for each region are listed by name, along with a series of generic options for respondents who don’t live in one of the places specifically listed, such as ‘A small city (10,000 - 100,000)’; ‘A village (less than 10,000)’; and ‘Rural area’. The current database serves more than 200 countries and includes the names of regions and cities in the languages of these countries. The database holds more than 20,000 entries. WageIndicator uses the REGION database for its multilingual salary survey, salary check and cost-of-living survey. Since 2008, millions of web visitors have satisfactorily completed the residence survey question without any problems.
The database contains a MAPPING TABLE, that identifies the urbanisation degree, based on the city size. This variable has seven options for the degree of urbanisation, ranging from ‘A metropolitan city (2 million or more)’ to ‘Rural area’. For European countries, the MAPPING table provides the NUTS codes, which are in use in statistical offices. Currently, the database is checked for its correspondence with the regions used in visualisation software so that its data can easily be used for visualisations.