Re: The meaning of Subject (and Coverage)
I'm not sure that doing both (that is, in some circumstances adding both a coverage and about statement with the same triple subject and object) resolves the problem, as we would need to be able to identify those circumstances - and this requires the same level of definition clarity as for coverage and about (subject) as independent properties. I wonder what the effect might be on end-user applications. As I suggested before, including the objects of dct:coverage instance triples in a subject index may lead to false drops; at least, what are considered false drops by the user. Some users may see jurisdiction as being an about entry (happy to retrieve the Lake Michigan waterfront resource in a search for stuff about Lake Michigan), while others may not. On the other hand, major KOSs often conflate/confuse subject with genre and form, so I'm probably being too precise - it's usually better to err on the side of recall in large-scale, high-level resource discovery systems, isn't it? Cheers Gordon On 27 February 2012 at 22:26 Diane Hillmann metadata.ma...@gmail.com wrote: here, but I'd like to add a few use cases here (informally, of course). As a former law librarian, the notion of geographic 'coverage' that isn't explicitly of a subject nature is pretty common. Jurisdiction is one such thing, and the kinds of laws that get passed by one jurisdiction applying only to a subset of the geographic area that is the jurisdiction is another. So for instance, the illinois legislature passes a law that applies only to a specific state resource, say the waterfront along Lake Michigan. You have two geographic instances here that are not necessarily subjects. The law is not 'about' Illinois, nor is it really 'about' the Lake Michigan waterfront. I know that many will protest this as similar to Karen's 'map of San Francisco', and it is in some respects. However, I happen to think that no bytes are harmed if we do both, and for the legal beagles, the 'applies' to idea exemplified by 'coverage' is pretty important. Diane
Re: The meaning of Subject (and Coverage)
I was thinking, as Karen suggests, that an AP would specify, say, that the range of dct:subject and similar properties is the VES GeoNames. An AP for a museum community might specify AAT as the VES; another AP might specify the VES as a union of GeoNames and AAT. Interoperability and inter-KOS relationships are established by mappings between KOSs, not hard-wired into a set of sub-properties. The case of literals is very interesting. It is tempting to disambiguate the literal China by using properties like has as subject (place), has as subject (person) (the cover of Sunfighter by Kantner/Slick), has as subject (ceramics), has as subject (housekeeping), etc. But that shifts the issue from values in a KOS to properties in a metadata schema. That is, the knowledge is organized via a KOS in some circumstances, and by a schema in others. Subject instance triples with literal objects are plain messy - but they are probably going to be in the majority in the triple soup through generation by social networking sites using uncontrolled so-called folksonomies. And we can't expect folks to choose which specific-subject property they're gonna use, or enter a term appropriate to a pre-set property, or even be aware of the issues. (And some of those folks are, sadly, professional librarians ...) I think management through KOS is probably better than through schema properties; presumably it is easier to apply machine-mediated quality control by ensuring that the object of a has as subject property is from a named KOS than it is to determine that dog is not an appropriate object for a has as subject (place) property. I think the divided world Karen foresees is inevitable. These issues have been around for a long time, and I guess RDF/Semantic Web/linked data technologies are not going to provide a better means of resolving them. +++ for FKOS! Surely some work is going on somewhere towards this? Are we seeing the emergence of APs for KOSs? It strikes me that FKOS is a named-graph pattern similar to what is being discussed in DC-Architecture about the DC Abstract Model and APs [1]. Other patterns are suggested by the FRSAD analysis of subject categorization. Can the SoDC-CL proposed by Alistair Miles [2] cover FKOS and other patterns? Cheers Gordon [1] https://www.jiscmail.ac.uk/cgi-bin/webadmin?A2=ind1202L=dc-architectureP=31326 [2] https://www.jiscmail.ac.uk/cgi-bin/webadmin?A2=ind1202L=dc-architectureP=30886 On 27 February 2012 at 20:42 Karen Coyle kco...@kcoyle.net wrote: On 2/27/12 10:53 AM, gor...@gordondunsire.com wrote: There is no requirement for a specific-subject (sub-)property such as frbrer:has as subject (place) (and its 10 companions, one for each Group entity), because this can be represented by an Application Profile Vocabulary Encoding Scheme or KOS, for example LCSH, DDC, local SKOS vocabulary, etc. I don't see how an AP resolves this, that is, how an AP overcomes the lack of a subject (place). I do think that to some extent vocabularies can help if the values are represented by URIs from vocabularies that specify a subject type. If your value is an entry from GeoNames, or is a geographical subject from LCSH, then you probably have what you need to clarify that the subject is a place. But dct:subject can have literals as values, and for those there is no distinction. What one might end up with is a metadata world where those distinctions between types are available only for some RDF-defined vocabularies but not for literals. Actually, that seems to be what we have today for dct:subject. We should also note that we don't yet have a way to describe a vocabulary that has facets. In part that is what was attempted with MADS in RDF, but unfortunately that ontology is forced to replicate the whole of the MARC Authorities record, so it's a bit messy. I think it would be interesting to postulate a FKOS - faceted knowledge organization system - language.
Re: The meaning of Subject (and Coverage)
I know you guys have been discussing it, but I still don't understand why a secondary/qualifying subject needs a completely different vocabulary term? If it's still aboutness, that seems like it should be the same term. I mean, sometimes in LCSH there's a third or fourth level of additional 'constraint' too -- do we need a seperate term for each possible 'level' of qualification, to handle every possible subject language that might have indefinite number of qualifications? That seems like poor modelling. I'm no RDF expert though, it may be that in RDF it's difficult to do this what seems to be the 'obvious' way, one vocabulary term for 'aboutness' with some other kind of structure indicating that X is a an 'aboutness term', while Y is another 'aboutness term' constraining/qualifying X? On the other hand, I DO understand the arguments that there's something _other_ than 'aboutness' at play here, eg in the case of legal documents which 'cover' something but are not 'about' it, and a different vocabulary term is needed there to distinguish between 'aboutness' terms, and this other thing, called 'coverage'. That seems reasonable, although it also seems likely to be confusing in practice, but that's not neccesarily a reason to avoid it, if it's neccesary to express data that important parts of our communities need. On 2/28/2012 5:20 AM, gor...@gordondunsire.com wrote: The dual roles of primary subject and secondary/qualifying subject are widespread beyond space and time. Research, education, training, analysis, ecology, etc. can all be primary topics or qualify other primary topics. I vaguely recall that these are generally treated as Energy facet concepts by Ranganathan - it's all a bit hazy. Cheers Gordon On 27 February 2012 at 20:42 Karen Coylekco...@kcoyle.net wrote: On 2/27/12 10:53 AM, gor...@gordondunsire.com wrote: Is it because the Space and Time facets in many library KOSs (reflected in Ranganathan's PMEST facet citation pattern) occupy a special place; i.e. can refine/qualify most other primary topics? I think it's more complex than that, but it is true that space and time are common facets in subjects. The complexity comes about, IMO, because places (and perhaps very rarely, times) can be subjects in themselves as well as qualifiers on other subjects. Without specific structure (a' la Ranganathan) it's hard to interpret whether a place name is a topic in itself or essentially an adjective on the topic: e.g. are these equivalent: dc:subject France dc:subject Cooking dc:subject French cooking This is a problem with other combinations of terms (Dogs Cooking), but the geographic case tends to get singled out because it is so common.
Re: The meaning of Subject (and Coverage)
Hi Diane, On Tue, Feb 28, 2012 at 11:22:10AM -0500, Diane Hillmann wrote: It was these folks who developed the DCMI Box and DCMI Point methods for encoding that info in text strings within Coverage. This was a while ago, and DC no longer supports those strategies... While it is true that DCMI no longer supports DCMI Box and DCMI Point in their original form [1,2], these specifications were revised in 2006 in a way that brought them into conformance with the notion of an RDF datatype [3,4]. The DCMI metadata terms: http://purl.org/dc/terms/Box [5] http://purl.org/dc/terms/Point [6] are Datatypes. The terms Box and Point, as well as the specifications DCMI Box and DCMI Point, are all still DCMI Recommendations. Though DCMI no longer actively promotes their use, they _are_ still supported... Tom [1] http://dublincore.org/documents/2000/07/28/dcmi-box/ [2] http://dublincore.org/documents/2000/07/28/dcmi-point/ [3] http://dublincore.org/documents/2006/04/10/dcmi-box/ [4] http://dublincore.org/documents/2006/04/10/dcmi-point/ [5] http://dublincore.org/documents/dcmi-terms/#ses-Box [6] http://dublincore.org/documents/dcmi-terms/#ses-Point -- Tom Baker t...@tombaker.org
Re: The meaning of Subject (and Coverage)
Sorry if I've missed something in this thread, but I believe dc:coverage is at least in part a contribution from the archives and records management fields to DCMES. That is, a treaty or contract of sale or any other record could cover something (e.g., Vancouver, BC from now 'til 2020) and not be about the same thing (e.g., exchange of land rights from the crown to an indigenous nation). If this holds, and if RDA intends on being useful to both librarianship and archivy then it has to contend with different domain models such as this. I know it's my old axe at this point, but purpose guides design and implementation, and the purposes discussed below are very library-y ;-) -- not very archivy-y. I remember being in Singapore saying that we should to a UB AP to make the semantics of these two clearer without changing their DCTERMS domains and ranges, but that work item was never completed in the UB. Happy Monday, all! joe Joseph T. Tennis Assistant Professor The Information School University of Washington Reviews Editor, Knowledge Organization jten...@u.washington.edu faculty.washington.edu/jtennis On Feb 27, 2012, at 5:11 AM, Tillett, Barbara wrote: Couldn't the topic, i.e., Subject, be what the thing is about? We have other attributes to use for the form or genre or medium of performance or other aspects. - Barbara -Original Message- From: List for discussion on application profiles and mappings [mailto:DC-RDA@JISCMAIL.AC.UK] On Behalf Of Karen Coyle Sent: Friday, February 24, 2012 5:57 PM To: DC-RDA@JISCMAIL.AC.UK Subject: Re: [DC-RDA] The meaning of Subject (and Coverage) This is a great example of how hard it is to define topic of. In MARC21 data, there are subject headings that are geographical in nature (and they are coded as geographical subject headings not just subject headings: tag 651, as opposed to tag 650 for topical topics). Geographical subject headings are used when the primary topic of the resource is the geographical area (California -- History). You can also have geographical facets in subject headings (at least in LCSH). That is when there is a main topic (Dog breeding) with a geographical aspect (in Canada). There are also places in the record to put geographical info when the resource is itself geographical in nature (e.g. a map, which can get scale and coordinates).[1] So if your map is coded with geographical coordinates for Berkeley, California, can you consider Berkeley, California the subject of the map? I think many people would. There is also a field that gives hierarchical geographical access to publications like newspapers [2] based on where they are published (which is often their main topical coverage as well, such as The San Francisco Chronicle). Note that changing the definition of dc:subject also means re-thinking dc:coverage, which has this definition: The spatial or temporal topic of the resource, the spatial applicability of the resource, or the jurisdiction under which the resource is relevant. Is dc:coverage still to be used for space or temporal topic? If it is decided that space and temporal topics would be covered by dc:subject and dc:coverage is only suitable for ...the spatial applicability of the resource, or the jurisdiction under which the resource is relevant then we have to consider whether people will reasonably be able to make the distinction between spatial applicability and space... topic. Note that such a change also removes the temporal aspect of dc:coverage, at least as it is now defined. I think something would be lost by putting geographical names in subject. A bit less is lost if the geographical name is a URI within, say, GeoNames, that clearly indicates the geographicalness of the value. But DC doesn't require URIs. This is also true for temporal topics -- which probably actually need their own property apart from geographical aspects, but that's water under the bridge. I think changing the definition of dc:subject would, in fact, have to also change the definition of dc:coverage. In addition, it would require people to make the difficult distinction between topically about and geographically applicable, something that I think is extremely hard and therefore not something we should require of people using DC. The current situation is not ideal, by any means, but I believe that the suggested change would make it worse. kc [1]http://loc.gov/marc/bibliographic/bd034.html [2] http://www.loc.gov/marc/bibliographic/bd752.html On 2/24/12 1:20 PM, Thomas Baker wrote: Dear all, Since 2006, the usage comment for the definition of dc:subject (and since 2008, dcterms:subject) has included the following sentence [1,2,3]: To describe the spatial or temporal topic of the resource, use the Coverage element. The intent was to provide guidance on when to use Coverage: The spatial or
Re: The meaning of Subject (and Coverage)
Between Barbara's reply and Joe's it sounds like dc:coverage should be expressly NOT topical. Now I'm REALLY confused about what it's supposed to be. kc On 2/27/12 5:52 AM, Joseph Tennis wrote: Sorry if I've missed something in this thread, but I believe dc:coverage is at least in part a contribution from the archives and records management fields to DCMES. That is, a treaty or contract of sale or any other record could cover something (e.g., Vancouver, BC from now 'til 2020) and not be about the same thing (e.g., exchange of land rights from the crown to an indigenous nation). If this holds, and if RDA intends on being useful to both librarianship and archivy then it has to contend with different domain models such as this. I know it's my old axe at this point, but purpose guides design and implementation, and the purposes discussed below are very library-y ;-) -- not very archivy-y. I remember being in Singapore saying that we should to a UB AP to make the semantics of these two clearer without changing their DCTERMS domains and ranges, but that work item was never completed in the UB. Happy Monday, all! joe Joseph T. Tennis Assistant Professor The Information School University of Washington Reviews Editor, Knowledge Organization jten...@u.washington.edu faculty.washington.edu/jtennis On Feb 27, 2012, at 5:11 AM, Tillett, Barbara wrote: Couldn't the topic, i.e., Subject, be what the thing is about? We have other attributes to use for the form or genre or medium of performance or other aspects. - Barbara -Original Message- From: List for discussion on application profiles and mappings [mailto:DC-RDA@JISCMAIL.AC.UK] On Behalf Of Karen Coyle Sent: Friday, February 24, 2012 5:57 PM To: DC-RDA@JISCMAIL.AC.UK Subject: Re: [DC-RDA] The meaning of Subject (and Coverage) This is a great example of how hard it is to define topic of. In MARC21 data, there are subject headings that are geographical in nature (and they are coded as geographical subject headings not just subject headings: tag 651, as opposed to tag 650 for topical topics). Geographical subject headings are used when the primary topic of the resource is the geographical area (California -- History). You can also have geographical facets in subject headings (at least in LCSH). That is when there is a main topic (Dog breeding) with a geographical aspect (in Canada). There are also places in the record to put geographical info when the resource is itself geographical in nature (e.g. a map, which can get scale and coordinates).[1] So if your map is coded with geographical coordinates for Berkeley, California, can you consider Berkeley, California the subject of the map? I think many people would. There is also a field that gives hierarchical geographical access to publications like newspapers [2] based on where they are published (which is often their main topical coverage as well, such as The San Francisco Chronicle). Note that changing the definition of dc:subject also means re-thinking dc:coverage, which has this definition: The spatial or temporal topic of the resource, the spatial applicability of the resource, or the jurisdiction under which the resource is relevant. Is dc:coverage still to be used for space or temporal topic? If it is decided that space and temporal topics would be covered by dc:subject and dc:coverage is only suitable for ...the spatial applicability of the resource, or the jurisdiction under which the resource is relevant then we have to consider whether people will reasonably be able to make the distinction between spatial applicability and space... topic. Note that such a change also removes the temporal aspect of dc:coverage, at least as it is now defined. I think something would be lost by putting geographical names in subject. A bit less is lost if the geographical name is a URI within, say, GeoNames, that clearly indicates the geographicalness of the value. But DC doesn't require URIs. This is also true for temporal topics -- which probably actually need their own property apart from geographical aspects, but that's water under the bridge. I think changing the definition of dc:subject would, in fact, have to also change the definition of dc:coverage. In addition, it would require people to make the difficult distinction between topically about and geographically applicable, something that I think is extremely hard and therefore not something we should require of people using DC. The current situation is not ideal, by any means, but I believe that the suggested change would make it worse. kc [1]http://loc.gov/marc/bibliographic/bd034.html [2] http://www.loc.gov/marc/bibliographic/bd752.html On 2/24/12 1:20 PM, Thomas Baker wrote: Dear all, Since 2006, the usage comment for the definition of dc:subject (and since 2008, dcterms:subject) has included the following sentence [1,2,3]: To describe the spatial or temporal topic of the resource, use the Coverage element. The intent was to
Re: The meaning of Subject (and Coverage)
I'm not sure who is channeling who here, but this is now the 2nd time that Simon and I have given approximately the same replies, and if it happens again it'll be creepy. :-) kc On 2/27/12 12:12 PM, Simon Spero wrote: On Feb 27, 2012, at 1:53 PM, gor...@gordondunsire.com mailto:gor...@gordondunsire.com wrote: It seems that the cover attribute/relationship has been conflated with the about attribute/relationship Is it because the Space and Time facets in many library KOSs (reflected in Ranganathan's PMEST facet citation pattern) occupy a special place; i.e. can refine/qualify most other primary topics? There are two distinct notions that are in play here: 1) A Geospatial/Temporal region can be considered as the main subject of a conceptual work. E.g. http://lccn.loc.gov/96002026 Main title:Lake Huron Subjects:Huron, Lake (Mich. and Ont.). 2) A Geospatial/Temporal region can be considered as narrowing the main subject of the work. E.g. http://lccn.loc.gov/74153794 Main titleLake Huron: the ecology of the fish community and man's effects on it SubjectsFisheries--Huron, Lake (Mich. and Ont.). The subject of (1) indicates a general work about the specified region. The second subject is necessarily also about some aspect of the specified region (subsumption holds), but it is primarily about Fisheries, narrowed to that region; coverage of other aspects of the region may be incidental at best. The use of a subdivided heading, rather than two separate headings, allows one to believe with justification that a topic related to the region, but not related to fisheries is less likely to be significantly covered in the second work. There are problems that occur when the only available predicate for 4d coverage is at the resource level; when a work is about multiple subjects with disjoint 4-space coverage, coverage statements detached from their subjects leads to incorrect entailments or information loss. A work level coverage scope may be determinable as a (possibly) non-contiguous 4d regions; alternatively the coverage may be broadened to a region containing all subregions, or alternatively it may be narrowed to the region which covers the bulk of the materials (a common archival practice). Simon -- Karen Coyle kco...@kcoyle.net http://kcoyle.net ph: 1-510-540-7596 m: 1-510-435-8234 skype: kcoylenet
Re: The meaning of Subject (and Coverage)
I'm not sure who I'm replying to here, but I'd like to add a few use cases here (informally, of course). As a former law librarian, the notion of geographic 'coverage' that isn't explicitly of a subject nature is pretty common. Jurisdiction is one such thing, and the kinds of laws that get passed by one jurisdiction applying only to a subset of the geographic area that is the jurisdiction is another. So for instance, the illinois legislature passes a law that applies only to a specific state resource, say the waterfront along Lake Michigan. You have two geographic instances here that are not necessarily subjects. The law is not 'about' Illinois, nor is it really 'about' the Lake Michigan waterfront. I know that many will protest this as similar to Karen's 'map of San Francisco', and it is in some respects. However, I happen to think that no bytes are harmed if we do both, and for the legal beagles, the 'applies' to idea exemplified by 'coverage' is pretty important. Diane
Re: The meaning of Subject (and Coverage)
On 2/24/12 6:38 PM, Thomas Baker wrote: To be clear, the definition of dc:subject would remain unchanged: The topic of the resource. No definitions would change. The change I am proposing is that the usage guideline -- that Coverage be used instead of Subject to describe the spatial or temporal topic of the resource -- be dropped. This does not mean that anyone would have to change what they are doing -- e.g., to start using Subject for describe spatial or temporal topics instead of Coverage. However, it is not incorrect to use Subject with a spatial or temporal topic, and removing the usage guideline would remove any ambiguity in this regard. But aren't the guidelines guidelines not rules? The question is not what is or isn't in the guidelines, but what we think is the best practice. Note that the *definition* of dc:coverage includes spatial and temporal *topics*. Are you saying that you wish for there to be two options for spatial and temporal topics? I think that removing the usage guideline means the answer to that is yes. So I ask: is that a good idea? I also think that because the definition of dc:coverage explicitly states spatial and temporal topics, without some explanation there is increased ambiguity when the guideline is removed. kc Tom -- Karen Coyle kco...@kcoyle.net http://kcoyle.net ph: 1-510-540-7596 m: 1-510-435-8234 skype: kcoylenet
Re: The meaning of Subject (and Coverage)
All My first point when discussing this with Tom was that there seems to be an inconsistency in the way dct:coverage is defined. dct:coverage and its sub-properties dct:spatial and dct:temporal include the subject aspect of their semantic in the definition. But this is not the case with any other dct attribute. For example, dct:language has definition A language of the resource., not The language topic of the resource, or a language of the resource. This is not inconsistent, however, if we propose that the definition of dct:coverage is intended to be entirely subsumed by the definition of subject. That is, the spatial applicability of the resource, or the jurisdiction under which the resource is relevant is intended to refer to the topicality or aboutness of the resource; the spatial applicability and jurisdiction are assumed to be spatial topics of the resource. This appears to be supported by Karen's observation if your map is coded with geographical coordinates for Berkeley, California, can you consider Berkeley, California the subject of the map? I think many people would. I expect similar arguments to be made for jurisdiction: that the geographical applicability of legislation is about that geographical entity. This implies: dct:coverage rdfs:subPropertyOf dct:subject . Then: dct:spatial rdfs:subPropertyOf dct:coverage . dct:temporal rdfs:subPropertyOf dct:coverage . entails: dct:spatial rdfs:subPropertyOf dct:subject . dct:temporal rdfs:subPropertyOf dct:subject . But the definitions of dct:spatial (Spatial characteristics of the resource) and dct:temporal (Temporal characteristics of the resource) are consistent with dct:language, and we don't generally want to say: dct:language rdfs:subProperty dct:subject . A document in a written language is not about that language, etc. This tends to suggest that the proposition that dct:coverage is a sub-property of dct:subject by virtue of its intended (but possibly unclear) definition is incorrect. That is, dct:coverage has a scope beyond aboutness. This results in a problem for applications requiring an index of all subjects/topics about a resource. A subject index needs to cover the objects of triples using dct:coverage, dct:spatial, and dct:temporal, as well as dct:subject, and will thus include values which are not about the resource (i.e. false drops). And the same problem will arise when mapping elements from other bibliographic namespaces to dct. Cheers Gordon On 25 February 2012 at 14:15 Karen Coyle kco...@kcoyle.net wrote: On 2/24/12 6:38 PM, Thomas Baker wrote: To be clear, the definition of dc:subject would remain unchanged: The topic of the resource. No definitions would change. The change I am proposing is that the usage guideline -- that Coverage be used instead of Subject to describe the spatial or temporal topic of the resource -- be dropped. This does not mean that anyone would have to change what they are doing -- e.g., to start using Subject for describe spatial or temporal topics instead of Coverage. However, it is not incorrect to use Subject with a spatial or temporal topic, and removing the usage guideline would remove any ambiguity in this regard. But aren't the guidelines guidelines not rules? The question is not what is or isn't in the guidelines, but what we think is the best practice. Note that the *definition* of dc:coverage includes spatial and temporal *topics*. Are you saying that you wish for there to be two options for spatial and temporal topics? I think that removing the usage guideline means the answer to that is yes. So I ask: is that a good idea? I also think that because the definition of dc:coverage explicitly states spatial and temporal topics, without some explanation there is increased ambiguity when the guideline is removed. kc Tom -- Karen Coyle kco...@kcoyle.net http://kcoyle.net ph: 1-510-540-7596 m: 1-510-435-8234 skype: kcoylenet
Re: The meaning of Subject (and Coverage)
Gordon, this now makes sense, thanks. I agree that it makes sense for all subjects to be under subject -- it also makes sense to me to have subject types as sub-properties of dc:subject. How far to go down that road is another question. I'm still confused, though, about the desired scope of dc:coverage. This tends to suggest that the proposition that dct:coverage is a sub-property of dct:subject by virtue of its intended (but possibly unclear) definition is incorrect. That is, dct:coverage has a scope beyond aboutness. I agree that it goes beyond aboutness, but the question is: is the non-topical aspect of coverage useful? Should the two uses (topical vs. 'spatial applicability') be split between dc:subject and dc:coverage? (I also wonder if it makes sense to put spatial and temporal together.) That said, we seem to be discussing some fundamental changes to DC terms, and I'm not sure that's practical. I can understand why one proposed solution was to remove the guidance statement from dc:subject, because that doesn't significantly change DC terms. But the issue seems to be that dc:coverage is encroaching on dc:subject in an odd way, and it is the definition of dc:coverage that would need to be changed, as well as its relationship to dc:subject. This is then a significant change and clearly would need serious consideration. kc On 2/25/12 11:07 AM, gor...@gordondunsire.com wrote: All My first point when discussing this with Tom was that there seems to be an inconsistency in the way dct:coverage is defined. dct:coverage and its sub-properties dct:spatial and dct:temporal include the subject aspect of their semantic in the definition. But this is not the case with any other dct attribute. For example, dct:language has definition A language of the resource., not The language topic of the resource, or a language of the resource. This is not inconsistent, however, if we propose that the definition of dct:coverage is intended to be entirely subsumed by the definition of subject. That is, the spatial applicability of the resource, or the jurisdiction under which the resource is relevant is intended to refer to the topicality or aboutness of the resource; the spatial applicability and jurisdiction are assumed to be spatial topics of the resource. This appears to be supported by Karen's observation if your map is coded with geographical coordinates for Berkeley, California, can you consider Berkeley, California the subject of the map? I think many people would. I expect similar arguments to be made for jurisdiction: that the geographical applicability of legislation is about that geographical entity. This implies: dct:coverage rdfs:subPropertyOf dct:subject . Then: dct:spatial rdfs:subPropertyOf dct:coverage . dct:temporal rdfs:subPropertyOf dct:coverage . entails: dct:spatial rdfs:subPropertyOf dct:subject . dct:temporal rdfs:subPropertyOf dct:subject . But the definitions of dct:spatial (Spatial characteristics of the resource) and dct:temporal (Temporal characteristics of the resource) are consistent with dct:language, and we don't generally want to say: dct:language rdfs:subProperty dct:subject . A document in a written language is not about that language, etc. This tends to suggest that the proposition that dct:coverage is a sub-property of dct:subject by virtue of its intended (but possibly unclear) definition is incorrect. That is, dct:coverage has a scope beyond aboutness. This results in a problem for applications requiring an index of all subjects/topics about a resource. A subject index needs to cover the objects of triples using dct:coverage, dct:spatial, and dct:temporal, as well as dct:subject, and will thus include values which are not about the resource (i.e. false drops). And the same problem will arise when mapping elements from other bibliographic namespaces to dct. Cheers Gordon On 25 February 2012 at 14:15 Karen Coylekco...@kcoyle.net wrote: On 2/24/12 6:38 PM, Thomas Baker wrote: To be clear, the definition of dc:subject would remain unchanged: The topic of the resource. No definitions would change. The change I am proposing is that the usage guideline -- that Coverage be used instead of Subject to describe the spatial or temporal topic of the resource -- be dropped. This does not mean that anyone would have to change what they are doing -- e.g., to start using Subject for describe spatial or temporal topics instead of Coverage. However, it is not incorrect to use Subject with a spatial or temporal topic, and removing the usage guideline would remove any ambiguity in this regard. But aren't the guidelines guidelines not rules? The question is not what is or isn't in the guidelines, but what we think is the best practice. Note that the *definition* of dc:coverage includes spatial and temporal *topics*. Are you saying that you wish for there to be two options for spatial and temporal topics? I think that removing the
Re: The meaning of Subject (and Coverage)
Folks: As I recall, the change in the definition of 'Coverage' to include topicality occurred while I was still on the UB, and I'd like to think I spoke against it (though I have no evidence for that, just memory, faulty at best). Tom, who probably has to hand all the minutes of those meetings might be able to pinpoint the time the decision was made, and maybe even the conversations around that change, since he wrote all the reports. That said, I agree with Gordon--the problem is also with the definition of Coverage, which says: Definition:The spatial or temporal topic of the resource, the spatial applicability of the resource, or the jurisdiction under which the resource is relevant.Comment:Spatial topic and spatial applicability may be a named place or a location specified by its geographic coordinates. Temporal topic may be a named period, date, or date range. A jurisdiction may be a named administrative entity or a geographic place to which the resource applies. Recommended best practice is to use a controlled vocabulary such as the Thesaurus of Geographic Names [TGN]. Where appropriate, named places or time periods can be used in preference to numeric identifiers such as sets of coordinates or date ranges. * * The Comment reinforces that definition, and its emphasis on topicality. Then I looked at 'Using Dublin Core' ( http://dublincore.org/documents/usageguide/elements.shtml) which was last updated (by me, probably), in 2005, and it does not mention topicality at all: *Label: Coverage* *Element Description:* The extent or scope of the content of the resource. Coverage will typically include spatial location (a place name or geographic co-ordinates), temporal period (a period label, date, or date range) or jurisdiction (such as a named administrative entity). Recommended best practice is to select a value from a controlled vocabulary (for example, the Thesaurus of Geographic Names [Getty Thesaurus of Geographic Names, http://www. getty.edu/research/tools/vocabulary/tgn/http://www.getty.edu/research/tools/vocabulary/tgn/]). Where appropriate, named places or time periods should be used in preference to numeric identifiers such as sets of co-ordinates or date ranges. *Guidelines for content creation:* Whether this element is used for spatial or temporal information, care should be taken to provide consistent information that can be interpreted by human users, particularly in order to provide interoperability in situations where sophisticated geographic or time-specific searching is not supported. For most simple applications, place names or coverage dates might be most useful. For more complex applications, consideration should be given to using an encoding scheme that supports appropriate specification of information, such as DCMI Periodhttp://dublincore.org/documents/dcmi-period/ , DCMI Box http://dublincore.org/documents/dcmi-box/ or DCMI Point.http://dublincore.org/documents/dcmi-point/ *Examples:* Coverage=1995-1996 Coverage=Boston, MA Coverage=17th century Coverage=Upstate New York My [faulty] memory suggests to me that the decision to include topicality in Coverage occurred around the time that we added domains and ranges, at which time I think we made some adjustments in definitions and comments. As Tom points out, the newer guidelines are likely to follow those changes closely (though for the life of me I can't find that document to quote from it). In any case, it seems to me that Gordon's logic is, as usual, impeccable, and we should consider specifically returning to the previous definition (or something new) that does not assume topicality, and perhaps even eschews that usage. I understand Karen's concerns completely (having taught this stuff since the dinosaurs walked the earth), and the questions I've answered over the years support her contention that people will not find this distinction easy to make, but I still think we should make it. Diane P.S. I've copied the Vocabulary Management Community list on this, under the assumption that they, too, will be interested in how this sausage is made. On Sat, Feb 25, 2012 at 2:07 PM, gor...@gordondunsire.com gor...@gordondunsire.com wrote: All My first point when discussing this with Tom was that there seems to be an inconsistency in the way dct:coverage is defined. dct:coverage and its sub-properties dct:spatial and dct:temporal include the subject aspect of their semantic in the definition. But this is not the case with any other dct attribute. For example, dct:language has definition A language of the resource., not The language topic of the resource, or a language of the resource. This is not inconsistent, however, if we propose that the definition of dct:coverage is intended to be entirely subsumed by the definition of subject. That is, the spatial applicability of the resource, or the jurisdiction under which the resource is relevant is intended to refer to the topicality or aboutness of the resource;
Re: The meaning of Subject (and Coverage)
Thanks, Diane, for the history. It's always hard to understand without the subtext of *how* things have come about. I have no strong interest one way or the other about a solution. But I am curious to know what usage of dc:coverage you prefer that would return to the previous definition (or something new) that does not assume topicality, and perhaps even eschews that usage. A few examples would probably make things clearest. I realize that you gave examples in your post, but without the context it isn't possible to know if these eschew the topical usage. (And, yes, I realize that there will be a considerable grey area between topical and non-topical, and I don't feel a need to disambiguate the whole world, just to see a few clear cases, which, then, may be useful in the documentation.) Thanks, kc On 2/25/12 12:00 PM, Diane Hillmann wrote: Folks: As I recall, the change in the definition of 'Coverage' to include topicality occurred while I was still on the UB, and I'd like to think I spoke against it (though I have no evidence for that, just memory, faulty at best). Tom, who probably has to hand all the minutes of those meetings might be able to pinpoint the time the decision was made, and maybe even the conversations around that change, since he wrote all the reports. That said, I agree with Gordon--the problem is also with the definition of Coverage, which says: Definition: The spatial or temporal topic of the resource, the spatial applicability of the resource, or the jurisdiction under which the resource is relevant. Comment:Spatial topic and spatial applicability may be a named place or a location specified by its geographic coordinates. Temporal topic may be a named period, date, or date range. A jurisdiction may be a named administrative entity or a geographic place to which the resource applies. Recommended best practice is to use a controlled vocabulary such as the Thesaurus of Geographic Names [TGN]. Where appropriate, named places or time periods can be used in preference to numeric identifiers such as sets of coordinates or date ranges. / / The Comment reinforces that definition, and its emphasis on topicality. Then I looked at 'Using Dublin Core' (http://dublincore.org/documents/usageguide/elements.shtml) which was last updated (by me, probably), in 2005, and it does not mention topicality at all: /Label: Coverage/ /Element Description:/ The extent or scope of the content of the resource. Coverage will typically include spatial location (a place name or geographic co-ordinates), temporal period (a period label, date, or date range) or jurisdiction (such as a named administrative entity). Recommended best practice is to select a value from a controlled vocabulary (for example, the Thesaurus of Geographic Names [Getty Thesaurus of Geographic Names, http://www. getty.edu/research/tools/vocabulary/tgn/ http://www.getty.edu/research/tools/vocabulary/tgn/]). Where appropriate, named places or time periods should be used in preference to numeric identifiers such as sets of co-ordinates or date ranges. /Guidelines for content creation:/ Whether this element is used for spatial or temporal information, care should be taken to provide consistent information that can be interpreted by human users, particularly in order to provide interoperability in situations where sophisticated geographic or time-specific searching is not supported. For most simple applications, place names or coverage dates might be most useful. For more complex applications, consideration should be given to using an encoding scheme that supports appropriate specification of information, such as DCMI Period http://dublincore.org/documents/dcmi-period/, DCMI Box http://dublincore.org/documents/dcmi-box/ or DCMI Point. http://dublincore.org/documents/dcmi-point/ /Examples:/ Coverage=1995-1996 Coverage=Boston, MA Coverage=17th century Coverage=Upstate New York My [faulty] memory suggests to me that the decision to include topicality in Coverage occurred around the time that we added domains and ranges, at which time I think we made some adjustments in definitions and comments. As Tom points out, the newer guidelines are likely to follow those changes closely (though for the life of me I can't find that document to quote from it). In any case, it seems to me that Gordon's logic is, as usual, impeccable, and we should consider specifically returning to the previous definition (or something new) that does not assume topicality, and perhaps even eschews that usage. I understand Karen's concerns completely (having taught this stuff since the dinosaurs walked the earth), and the questions I've answered over the years support her contention that people will not find this distinction easy to make, but I still think we should make it. Diane P.S. I've copied the Vocabulary Management Community list on this, under the assumption that they, too, will be interested in how this sausage is
Re: The meaning of Subject (and Coverage)
On 24 February 2012 22:20, Thomas Baker t...@tombaker.org wrote: Dear all, Since 2006, the usage comment for the definition of dc:subject (and since 2008, dcterms:subject) has included the following sentence [1,2,3]: To describe the spatial or temporal topic of the resource, use the Coverage element. The intent was to provide guidance on when to use Coverage: The spatial or temporal topic of the resource... [5] and when to use Subject, which had a clearly overlapping definition: The topic of the resource. [6] I recently had a chat about this with Gordon, who points out -- and I'll let him elaborate -- that current notions of subject (aboutness) do not treat spatial or temporal topics separately from any other topics. In my reading of meeting notes and decision documents from the time (see Background below), the addition of the sentence quoted above to the Comment for Subject was not intended as a clarification of the formal definition of Subject, but rather as guidance about which element to use at a time when people commonly wanted to use the fifteen elements in non-overlapping ways. If this usage guideline is now unhelpful, should it be removed (after due process of course)? Is this a bit like the relationship between 'creator', 'publisher' and the more general/vague 'contributor'? Dan Tom -- Background The sentence from the Comment for Subject, quoted above, was added at the time the definition of Coverage was changed from: The extent or scope of the content of the resource. [4] to: The spatial or temporal topic of the resource, the spatial applicability of the resource, or the jurisdiction under which the resource is relevant. [5] as explained in [3]. This brought the definition of Coverage very close to the definition of Subject: The topic of the resource. [6] At the time, it was widely felt that Dublin Core elements should not overlap in meaning; indeed, it was not until 2008 that Creator was declared to be a subproperty of Contributor [7]. As near as I can tell, then, the sentence quoted above was added to the usage comment for Subject in an effort to provide guidance to users about which element to use in a case where two definitions clearly overlapped. [1] http://dublincore.org/documents/dcmi-terms/#subject [2] http://dublincore.org/documents/dcmi-terms/#terms-subject [3] http://dublincore.org/usage/decisions/2006/2006-03.dcmes-changes.shtml [4] http://dublincore.org/documents/2006/08/28/dcmi-terms/#coverage [5] http://dublincore.org/documents/2006/12/18/dcmi-terms/#coverage [6] http://dublincore.org/documents/2006/12/18/dcmi-terms/#subject [7] http://dublincore.org/usage/decisions/2008/dcterms-changes/#sect-3 -- Tom Baker t...@tombaker.org
Re: The meaning of Subject (and Coverage)
On Fri, Feb 24, 2012 at 4:20 PM, Thomas Baker t...@tombaker.org wrote: I recently had a chat about this with Gordon, who points out -- and I'll let him elaborate -- that current notions of subject (aboutness) do not treat spatial or temporal topics separately from any other topics. I am not sure that this is entirely correct, at least in the case of the semantics of LCSH. It is possible for a concept intentionally referring to a 4-space region to be the main subject of a work- for example a film about France. However, in other cases a topical or other concept may be sub-divided so as to cover a narrower portion of the concept occurring within or relating to a 4-space region. For example, a documentary about 20th century french films. The full semantics are somewhat more complicated, due to the syntactic structure of subdivided headings, which does not reduce to a eufaceted structure. Simon [LCSH is strictly speaking 3d+1, but it's easier to think of it in 4d terms if one wants to also address FAST]
