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DEPRECATED Locality: model clarification

Michelle Koo edited this page Nov 8, 2023 · 1 revision

The Enhanced Advisory Committee/Arctos Working Group agrees to retain the current locality model for the foreseeable future. This document attempts to clarify some various points of confusion.

  1. The current model is a compromise with many "proper" data modeling attributes giving way to usability. Therefore, the data have a major impact on "spatial normalization" (eg, having the same 3d shape multiple times because the locality also includes remarks, or non-standard units are used). Developing collection procedures (eg, avoid unnecessary remarks, use meters for units) will help avoid the effects of denormalization (eg, updating lots of specimens instead of one locality).

  2. Everything in table locality are co-equal parts of the same THING, a three-dimensional shape + specific locality (and remarks, which should be avoided).

  3. Spatial data should be viewed as shapes; maximum error, elevation, and depth are NOT metadata of coordinates, they are primary data which define shapes. That is, changing any spatial attribute creates a new shape.

  4. Specimen Event Determiner takes responsibility for everything between specimens and place-data. Any assumptions regarding collectors, georeferencers, or other agents lead only to confusion.

  5. Arctos is primarily a specimen database, and so locality data are primarily important in the context of specimens. Perhaps unlike a Georeference Database, the path by which the data in table Locality came to exist is unimportant; simply don't use those which don't appropriately represent the specimen data.

  6. A specimen may have any number of specimen-events. You may use this to maintain a coordinate history (eg, "the old model") or to maintain a complete 4-dimensional spatiotemporal placement history. (Nothing was removed from "the old model;" "the new model" is an addition+normalizing shuffle.)

Guidelines for choosing Specimen Event Determiner:

  • Collector provided descriptive data? Collector should be specimen_event.assigned_by.
  • Collector somehow came up with coordinates? Collector should be specimen_event.assigned_by.
  • Student somehow came up with better/original/different coordinates? A new event should be created and student should be specimen_event.assigned_by.
  • Curator tightened up the error? A new event should be created and curator should be specimen_event.assigned_by.