This figure is a structure diagram for FPO as it is expressed in OWL and RDFS.
As is typical for diagrams of this kind, the boxes represent classes of objects in FPO, and the lines between them indicate semantic connections. There are two quite different kinds of connections shown.
- The double-line arrow represents a “subclass” connection. Since, for example, :FemalePerson is connected by one of these lines to :Person, we are meant to read this as saying that the :FemalePerson (like :MalePerson, or :Group) is a subclass of the more general concept of :Person. This is sometimes expressed as “a :FemalePerson is a kind of :Person”.
- The single-line arrow represents other kinds of relationships between classes, and are labelled to help specify the kind of relationship that each represents. Note, for example, the line that connects :Person to :DateRange and is labelled “:hasLifeDates”. This says that the :PersonClass can be connected to a specific :RateRange by the idea of a “Life Date”. Subclasses inherit relationships of these kinds. Thus, since :FemalePerson is a subclass of :Person, it also can specify Life Dates.
- Relationships defined in FPO which do not link to other classes but to numbers or bits of text (names for persons, for example) are called here “Properties” of a class, and not shown in this diagram, but are described in the detail section of the kinds of classes mentioned below.
The structure might appear quite complex to a new viewer, but it is useful to notice that it divides into several different areas, representing conceptually related parts, described below.
- Persons: The top left area of the diagram has the classes related to the representation of historical persons. They are described in more detail here.
- Sources: The top right area has the classes related to primary historical sources and the references to these sources. They are described in more detail here.
- Assertions/Factoids: below the area for Sources, and above the area for Dates and DateRanges, is the area where classes related to Factoids are defined. They are described in more detail here.
- References: In FPO, persons are connected to factoids through References, which are also used to connect factoids to geographical places (Locations). These classes are shown below the Persons area, and are described in more detail here.
- Locations and Possessions: in several KCL factoid prosopographies, geographic places and possessions, both land and non-land objects, play and important role. Classes for them are in the bottom left area of the diagram above, and are described in more detail here.
- Dates: Finally, since prosopographies are projects in the field of history, dates play an important role. The bottom right area of the diagram shows classes related to dates and date ranges, and are described in more detail here.