Rules to infer collection dates for museum occurrences

We have found that some museum specimens are not labeled with their date of collection. In these cases, we use auxilliary information to bracket the date of collection by its Earliest* and Latest* possible years of collection.

To do so, we apply the following rules in order:

  • First, we consider notes associated with the specimen. For example, if a specimen contains the note, "collected in the 1880's", then the Earliest* and Latest* values are 1880 and 1889, respectively.
  • Then, we consider information about the collector, using the earliest and latest documented collections by that collector as the Earliest* and Latest* values .
  • Next, we consider information about the collection with which the specimen is associated. Values for Earliest* and Latest* are then the earliest and latest years documented for that collection.
  • Finally, if there is no information for former collection, collector, specimen, and no actual date of collection, then the value "-999" is used for Earliest*, while the current year is used for Latest*.