Temporal Recording Methodology

One of the issues with historical dating information is the uncertainty surrounding dating information - both at the level of actual knowledge of the dates and at the level of interpretation of the evidence leading to the determination of a date.
What we aim to do is to provide a flexible methodology for capturing what we know about the dating of a site, object, event or conceptual category (eg. Levantine Bronze Age, ‘early 20th century’) which allows the recorder to capture as much of their knowledge as possible without loading them down with time-consuming and non-reproducible recording of information.

Some ideas for collecting uncertain dating information

We have taken two complementary approaches to storing uncertain dating information, reflecting both the uncertain nature of the dates themselves and the interpretation which leads to assignment of dates to an observed or conceptual entity.

Temporal objects

We have developed a methodology for storing accurate dates, statistical dates (eg. C14) and uncertain or fuzzy dates as temporal objects in the Heurist database. The data is stored in a textual format and manipulated through a Javascript library, which will be released as part ogf, and is thus portable to other databases or file formats such as XML.

A provisional data entry interface for dating information has been developed, as shown below.

Date range (analyst has ideas about limits on the date)

Approximate date (analyst has a rough idea about the date)

Recording events

Mostern and Johnson (2008) have argued that history can be modelled as nested events, and that many entities regarded as distinct phenomena - places, cultures, periods etc. - can in fact be regarded as events. Our modelling therefore revolves around historical events and the attribution of dating to those events.

Date attributions are always a matter of interpretation and this interpretation may be spatial as well as temporal. Furthermore, many date attributions consist of assigning an entity to an existing interpretation (such as identifying an object as belonging to the Solutrean III due to its stratigraphic location or association with characteristic specimens or by its inherent style).

Approximate date (analyst has a rough idea about the date)

Heurist event records record a start date, an end date and (optionally) a duration and any number of intermediate (‘attested’) dates, each of which is a composite object made up of:

  1. a temporal object (Start date object, End date object)
  2. a temporal interpretation (Start date interpretation, End date interpretation)
  3. optional dating references (Not shown above)


Temporal (and spatial) interpretations are recorded as a separate record linked to the event with Heurist’s relationship mechanism. They include authorship, a summary, a timestamp and further links to references which are relevant to the interpretation. They can also include extended WYSIWYG text, threaded discussions, images and so forth (provided by the standard mechanisms of the Heurist database).

Approximate date (analyst has a rough idea about the date)

Dating by reference

Where optional event references are supplied, these provide alternative interpretations of the dating. The use of references to existing events avoids the need to create redundant data for commonly used temporal terms, such as archaeological or historical periods. During our research we considered using distinct ‘temporal spans’ for dating information, but in the end decided that temporal spans were jsut events, folowing the Mostern and Johnson concept of primacy of events.

Typically, the start and end date temporal objects in an event may provide a ‘commonly understood’ or ‘simple’ dating range for the event, which will be used for most mapping and timeline applications, where a simple view of the data is required. This is the standard date-attribute approach to historical event dating.

However a researcher might wish to create and/or consult all the different possible interpretations of the dating of an event in order to be able to compare different viewpoints on disputed history or canvas different alternatives in a what-if scenario. These can be accommodated by linking alternative dating to an event. We do this by linking another event and applying a relationship type from a specific ontology of temporal assignments (under development): provisional assignment relationship terms include Precedes, Follows, FallsWithin, Includes, DerivesDatesFrom, DerivesStartDateFrom, DerivesEndDateFrom.

We are developing strategies for displaying multiple interpretations which might include filtering preferred opinions (eg. those of experts in a particular period, or from a particular research group) and displaying multiple interpretations with colour coding on a timeline.