WTF (What Type of Feature)? Classifying Features for Advanced Data - PowerPoint PPT Presentation

WTF (What Type of Feature)? ‐ Classifying Features for Advanced Data Linking, Searching and Analysis Capabilities International Cartographic Conference, Dresden Laura Kostanski | Pier ‐ Giorgio Zaccheddu| Linda Merrin | Rob Atkinson August 2013 GOVERNMENT AND COMMERCIAL SERVICES THEME

Today’s Presentation 1. Known Issues in this Domain 2. Possible Ways of Resolving Problems 3. Spatial Identifier Reference Framework (SIRF) 4. Next Steps

What Happened? Mildura , Victoria, Australia December 2012, Victoria Police warned motorists to not rely on maps produced by iOS6 “the official gazetteer – which is the authoritative reference for the names and locations of 384,104 places, objects and towns in the continent – contains an entry at the precise place to which Apple was directing hapless drivers until making a hurried correction on Monday” (Arthur, 2012) The Gazetteer of Australia contains over 380,000 place names, including 33 for Mildura .

Which Data? A search of the Gazetteer of Australia (www.ga.gov.au/place ‐ names) identifies 33 records which include the name ‘Mildura’, of these there are ‐ Mildura Rural City (with the same coordinates as where the tourists were unfortunately directed) ‐ Mildura (the actual township). The former is identified as POPL , while the latter is identified as LOCB . ‐ POPL is described by the Committee for Geographic Names Australasia (CGNA) as a ‘mapped populated place’ ‐ LOCB is described as a ‘Locality (bounded), Town, Village, Populated place, Local government town, Town site’.

Confused Feature Type Referencing From the original dataset, Victorian State Gazetteer ‐ Rural City of Mildura is a LGA ‐ government administrative region covering 22,214 square kilometres ‐ ‐ Mildura is a township, which the misdirected tourists were intent on visiting. A centroid coordinate of the expansive LGA boundary is positioned in the exact location to which hapless tourists were directed by iOS 6.

Composition of a Gazetteer Gazetteer entries consist of three minimum components ‐ 1. An identifier (names) [N] 2. Feature type [F] 3. Footprint (point, line or polygon) [T] An identifier (N) can often be utilised multiple times for different location instances, and it is more often than not the feature type (T) which is identified to disambiguate one reference from another. However, current practices can hamper the discoverability and reliability of data for end users.

Why Feature Typing? In the world of gazetteers, a feature can be described as a real world entity and a feature type is ascribed for categorization purposes (usually from a pre ‐ determined typing scheme or ontology) (Janowicz, 2008). Finney and Watts (2011) have identified three use ‐ case scenarios common to the discovery of feature ‐ level information ‐ ‐ data providers, when developing their exchange schema to check for conformity with community ‐ agreed standards on feature type definitions; ‐ dynamically by a machine client, attempting to resolve and interpret an online reference to some repository content, where the reference was located in an exchanged dataset; and, ‐ by a machine client requesting, or posting respository content to fulfill some component of its own internal functionality.

What is the problem? ‐ It is in the typing and categorization of gazetteer data that information can be correlated and linked to make it more readily accessible and understood by both machines (for processing queries) and humans (for application and use). ‐ Machines are incapable of interpreting and understanding geospatial data in a way similar to human capabilities (Wiegand & Garcia, 2007). ‐ One of the main metadata requirements therefore is the adequate description of geospatial data feature types, so that similar details can be discovered and linked across multiple heterogeneous systems.

Issues facing Interoperable Gazetteer Services Based on the available literature, it can be assumed that the general issues affecting the development of truly interoperable gazetteer services (both thesauri and ontologies) include ‐ ‐ Lack of clear definition of types (Zhao, Zhang, Wei, & Peng, 2008) ‐ Ambiguous referencing of types to categories (Jung, Sun, & Yuan, 2013) ‐ Missing metadata from original sources (Athanasis, Kalabokidis, Vaitis, & Soulakellis, 2009) ‐ Problems asserting ‘same ‐ as’ or ‘similar ‐ to’ definitions across gazetteers (Wiegand & Garcia, 2007) CSIRO. UNSDI Gazetteer for Social Protection in Indonesia

Ontology ‐ Defined Feature Catalogues • Various theorists prefer to explore the options for ontology ‐ defined feature catalogues. • An ontology is generally referred to as an ‘explicit specification of a conceptualization used to achieve a shared and common understanding of a particular domain of interest’ (Gruber, 1993). • An ontology includes specific reference to the characteristics of a feature type so that it might readily be distinguished from all others, while also being recognized with various relationship definitions for other types (such as the is ‐ a hierarchical relationship). • It also defines all relations so that the scope can be validated for query and reasoning services required or applied by users (Janowicz, 1132).

What is being done in this space? 1. Multiple international gazetteers and Feature Type Catalogues have emerged. 2. Two major catalogues referenced and accessed internationally  Alexandria Digital Library  Geonames.org 3. National Gazetteers and Regional Gazetteers Developed  INSPIRE  Australian Gazetteer Presentation title | Presenter name | Page 11

Alexandria Digital Library (ADL) 1. The ADL FTT has been segmented into six categories which contain amongst them 200 feature types:  administrative areas  hydrographic features  land parcels  manmade features  physiographic features  Regions 2. 209 ‘preferred terms’ and 978 ‘lead ‐ in terms’ Presentation title | Presenter name | Page 12

ADL ‐ Example of ‘School’ /concept/#id /concept/BT /concept/descriptor /concept/non ‐ descriptor /concept/NT /concept/RT /concept/UF 9 administrative areas school districts 18 agricultural schools 350 institutional sites educational facilities academies 350 institutional sites educational facilities agricultural schools 350 institutional sites educational facilities campuses 350 institutional sites educational facilities colleges 350 institutional sites educational facilities military schools 350 institutional sites educational facilities schools 350 institutional sites educational facilities seminaries 350 institutional sites educational facilities training centers 350 institutional sites educational facilities universities 350 institutional sites educational facilities library buildings 350 institutional sites educational facilities research facilities 679 military schools 1005 administrative areas school districts 1006 Schools Presentation title | Presenter name | Page 13

Geonames.org 1. 660 fine ‐ level feature codes mapped to 9 categories Category Description CODE A country, state, region,... H stream, lake, ... L parks, area, ... P city, village, ... R road, railroad S spot, building, farm T mountain, hill, rock,... U Undersea V forest, heath, ... Presentation title | Presenter name | Page 14

Geonames.org ‐ Example of ‘School’ Category Feature Feature Type Description CODE CODE S CTRM medical center a complex of health care buildings including two or more of the following: hospital, medical school, clinic, pharmacy, doctor's offices, etc. S CTRR religious center a facility where more than one religious activity is carried out, e.g., retreat, school, monastery, worship S MSSN mission a place characterized by dwellings, school, church, hospital and other facilities operated by a religious group for the purpose of providing charitable services and to propagate religion S MSSNQ abandoned mission S NOV novitiate a religious house or school where novices are trained S SCH school building(s) where instruction in one or more branches of knowledge takes place S SCHA agricultural school a school with a curriculum focused on agriculture S SCHC college the grounds and buildings of an institution of higher learning S SCHL language school Language Schools & Institutions S SCHM military school a school at which military science forms the core of the curriculum S SCHN maritime school a school at which maritime sciences form the core of the curriculum S SCHT technical school post ‐ secondary school with a specifically technical or vocational curriculum S UNIP university prep school University Preparation Schools & Institutions S UNIV university An institution for higher learning with teaching and research facilities constituting a graduate school and professional schools that award master's degrees and doctorates and an undergraduate division that awards bachelor's degrees. Presentation title | Presenter name | Page 15