Geocoding is the computational process of transforming a physical address description to a location on the Earth’s surface (spatial representation in numerical coordinates). Reverse geocoding, on the other hand, converts geographic coordinates to a description of a location, usually the name of a place or an addressable location. Geocoding relies on a computer representation of address points, the street/road network, together with postal and administrative boundaries. Geocoding is the process of finding a location (i.e. coordinate) for an address or another place name. The reliability of geocoding typically relies on two things: the accuracy and completeness of the address database, and the quality of the matching algorithm. The quality of the matching algorithm is more complicated. geocoder is having problems finding your street address, try to formalize the formatting and remove any abbreviations.
Most, if not all, consumer geocoders use a process of interpolation. This saves processing time and disk space by only storing the street numbers for the ends of street segments. Individual street numbers are then interpolated between the ends of these segments. As well as efficiency, this also has the advantage that the geocoder can make an intelligent estimate of the location for a new street number. However, the interpolation is itself an explicit assumption about address spacing, and also requires an assumption about the relative positioning of odd-numbered and even-numbered addresses. In other words, the exact position and side-of-street may not be correct.
Geocodes vs traditional addresses
Besides the strategic value that location data delivers, reliable coordinates are necessary for maintaining a reliable service. The costs of a transporter not being able to execute an order are not to be underestimated. When transporters are provided with unreliable specifications, the odds of that happening rise. For multiple reasons, geocoordinates mitigate that risk.
- Precision and accuracy
Addresses can be incorrect, inaccurate and unprecise. Incorrect because of a human mistake, inaccurate because a road network has changed, unprecise because an industrial area can be big and encompass multiple entrances. All these flaws can be fixed through geocoding.
Different countries work with the different metric system. These differences can lead to conversion miscalculations. History has shown that we should be cautious not to make these mistakes.
- Countries, regions, languages
Across countries, regions, and languages, latitude-longitudes are equal. Addresses, on the other hand, may cause problems. F.e. Belgium has nearly 500 streets named ‘Churchstreet’. Obviously, these frequently recurring street names can lead to misconceptions. Another example is a person or application knowing the address in Dutch but not in French. With geocoordinates, these issues do not exist.
Likewise, different applications do not necessarily locate one address in exactly the same spot. Again, this inconvenience can be prevented by using lat, longs (latitudes, longitudes) instead of addresses.
Road networks are evolving constantly. Since geocodes point to a physical fixed location on earth, they don’t change. By pointing to a latlon, you make abstraction of the roadmap. Data is guaranteed to be consistent, straightforward and clear.
Geocoding is a task which involves multiple datasets and processes, all of which work together. A geocoder is made up of two important components: a reference dataset and the geocoding algorithm. Each of these components is made up of sub-operations and sub-components. Without understanding how these geocoding processes work, it is difficult to make informed business decisions based on geocoding.
A simple method of geocoding is addressed interpolation. This method makes use of data from a street geographic information system where the street network is already mapped within the geographic coordinate space. Each street segment is attributed with address ranges (e.g. house numbers from one segment to the next). Geocoding takes an address, matches it to a street and specific segment (such as a block, in towns that use the “block” convention). Geocoding then interpolates the position of the address, within the range along the segment.