Geocoding user queries
Konstantin Clemens · DepositOnce · 2020
While human users refer to locations using toponyms and addresses, computers rely on latitude and longitude coordinates, or similar, numerical encoding of location information. Geocoding is the process of resolving such toponyms and addresses into machine-friendly numerical encoding. Thus, wherever human users need to specify a location to a computer, geocoding is involved. The process, thereby, is mainly dependent on two aspects. Firstly, the underlying address data needs to be complete, up-to-date, and accurate as otherwise, the geocoding result will not be precise. Secondly, the algorithms that process the user input query, browse candidates within the data and select the right result to the query need to be capable of handling queries of human users. In this thesis, the specifics of human input addresses are tackled. Various kinds of modifications occur to an address when humans are involved. For example, address formats are not adhered to, superfluous tokens are specified, while required parts of an address are left out of the query. Also, humans abbreviate, escape, or misspell address element names often. The goal of this thesis is to investigate the algorithmic aspect of geocoding systems. Throughout the thesis, ways to process, organize, index, and rank address data are investigated independently of the underlying data. As a result, a method for creating a geocoding system with good precision and recall metrics even in the face of the human factor is developed. A sequence of experiments is executed that gradually build on top of each other. First, the use of a generic document search engine as the index of a geocoding system is validated. Next, a suitable address model for indexing and searching is selected. Then, using log data from a live geocoding system, a statistical model is created that can be used to generate user-like requests. A similar approach based on the log data is evaluated to create geocoding systems that perform measurably better than geocoding systems relying on common methods to handle user queries. Finally, a process is developed that continuously improves a geocoding system using user queries issued against it. The measurements prove that the path chosen in this thesis is a viable method to create geocoding systems that can handle user queries better than geocoding systems relying on common techniques.