Dear Karen,

I agree with Simon - let's not use "properties" in this instance and instead use "Classes" or "types."

You asked: "In the case in which a subject heading consists of only one "subfield" (which is the same element that exists in a simple property), is a complexSubject created for this singlet?"

In short, no.  Whether enforced in the ontology at this time (or whether it is enforceable in the first place), a SimpleType - such as Topic, Geographic, Temporal - can be used as a standalone subject heading.  A ComplexSubject type is, to use a slightly different semantic label, essentially a pre-coordinated heading.  To reword the documentation ever so slightly:

ComplexSubject, HierarchicalGeographic, and NameTitle types, all of which are ComplexType types, are designed to handle records that are the aggregation of two or more SimpleType records.

A NameTitle, for example, is used when the first component is a Name type and a following component is a Title type.  But, if you had a Topic type followed by a Temporal Type, the aggregation of those two terms (the resulting pre-coordinated heading) would be a ComplexSubject, because it is composed of two SimpleType types (Topic and Temporal) *and* it does not meet the necessary conditions to be a NameTitle (or HierarchicalGeographic).

Does this help?  If not, I may be misunderstanding what you mean by "simple properties."

Cordially,

Kevin

________________________________________
From: Metadata Object Description Schema List [[log in to unmask]] On Behalf Of Karen Coyle [[log in to unmask]]
Sent: Sunday, December 05, 2010 18:59
To: [log in to unmask]
Subject: [MODS] madsrdf: Question about subject

Hi. I've read through the madsrdf document and tried to find the
answer to this among the examples, but didn't succeed. So apologies if
I missed something obvious.

There are simple properties like Topic or Geographic, then there are
complex subjects that are made up of combinations of simple
properties. In the case in which a subject heading consists of only
one "subfield" (which is the same element that exists in a simple
property), is a complexSubject created for this singlet?

The thrust of the question revolves around distinguishing a simple
property from an actual subject heading, given that not all simple
properties can be used as subject headings. Or am I misunderstanding
things?

Thanks,
kc

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Karen Coyle
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