Forward geocoding for select countries

Assumptions

Verisk Synergy Studio geocodes locations based on the following assumptions:

• Unsupported resolutions either do not exist or are not available in the data.
• Final geography records contain the desired/supported information and only the desired/supported information per country-specific requirements. That is, Verisk Synergy Studio fills or overwrites in both the forward and backward direction from existing data.
• Verisk Synergy Studio remaps older/retired codes to supported codes.
• When matching on a city, Verisk Synergy Studio uses all the fields from the tGeography record, except the geocode, which comes from the city data.
• The rules are based primarily on codes rather than names. The city is an exception, since there are no city codes. Verisk Synergy Studio supports attempts to match by names, but names do not have the same uniqueness as codes. Consequently, differences in spelling, spacing, abbreviations, or special character use in names often cause issues when matching by name only.

General rules

These are the rules that Verisk Synergy Studio follows when forward geocoding location data for locations in the countries for which Verisk Synergy Studio supports updated geocoding functionality:

• Resolution and, therefore, precedence from highest to lowest is generally as follows:

  1. Subarea 2
  2. Postal
  3. City
  4. Subarea
  5. Area
  6. CRESTA
  Note:

  • Verisk Synergy Studio ignores unsupported resolutions for matching, because they are not in the data for a given country.
  • City records usually link to postal geographies, but for countries that do not support postal data (such as Ireland) or in which the postal data is otherwise not appropriate (United Kingdom and Israel), city records link to other levels. In these cases, Verisk Synergy Studio still assigns this precedence to the city match.
• Verisk Synergy Studio geocodes to the highest-resolution valid, matching data.
• If the highest resolution match is to a remapped record, Verisk Synergy Studio geocodes instead with the linked supported record.
• The GeoMatchLevel is based on the final geography resolution, not the matching resolution.
• Verisk Synergy Studio can use a user-provided city (name) to geocode, but Verisk Synergy Studio never forward or backward fills or updates city data. City-driven matches use the CITY GeoMatchLevel and the city centroid in place of the corresponding information from the geography record. In other words, Verisk Synergy Studio retains the user-provided city name regardless of whether it is "right" or "wrong."
• If the highest-resolution matches are not unique, Verisk Synergy Studio reverts to lower-resolution matches until finding a unique match. If Verisk Synergy Studio reverts all the way to the country level, then the location is not eligible for loss.
• When following remapping paths, Verisk Synergy Studio gives precedence to CRESTA-based matches over area-based matches.

Known exceptions

When reverse geocoding locations in France, Guadeloupe, and Martinique, Verisk Synergy Studio retains user-supplied INSEE (National Institute of Statistics and Economic Studies) data if this data is valid for the matched postal data. If not, Verisk Synergy Studio discards the INSEE. Verisk Synergy Studio obtains the GeomatchLevel and GeographySID from the postal data, regardless of the INSEE match. Similarly, New Zealand retains user-supplied postal codes if they are valid for the matching input subarea 2 data.

Additional considerations for forward geocoding for select countries

• City: Verisk Synergy Studio city data contains many duplicate city names within a country. Some countries have multiple cities with the same name. Other cities are large and cross multiple areas at a given level. Verisk Synergy Studio makes a best effort to find a unique city match, but if Verisk Synergy Studio does not find a unique city match, Verisk Synergy Studio reverts to the next highest-resolution unique match.

  A unique, best-fit match using city and any other area level resolves immediately. When the best-fit records reflect multiple city records, Verisk Synergy Studio uses the following logic:

  1. If all records are in the same subarea, Verisk Synergy Studio falls back to the Subarea (SUBA) match.
  2. If there is a natural Subarea match available, Verisk Synergy Studio uses this Subarea (SUBA) match rather than considering city and area/CRESTA.
  3. If Verisk Synergy Studio has both area and CRESTA matches (which is an unusual situation), Verisk Synergy Studio chooses the area (AREA) match, except in the case of Italy or Portugal.
  4. If Verisk Synergy Studio has either CRESTA or area, Verisk Synergy Studio uses this CRESTA (CRES) or area (AREA).
  5. Otherwise, Verisk Synergy Studio cannot match using city data.
• Germany subarea to postal mapping: Sometimes the above-mentioned rules combine with the data to work out to unexpected outcomes. An example of this scenario occurs for locations in Germany when a provided valid postal code resolves to a different valid postal code, as in the following example:
  1. A user provides a location in Germany with "41468" as the subarea code.
  2. There are two such records, and Verisk Synergy Studio cannot choose between these two records.
  3. Verisk Synergy Studio resolves the duplicate postal name by falling back to the shared subarea "LK Alb-Donau-Kreis."
  4. Since German subareas are remapped to the postal level, Verisk Synergy Studio must follow this remapping link.
  5. The remapped postal record name is "Blaubeuren."