Text limits in LRMI

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Hugh Paterson III

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May 3, 2022, 12:12:14 PM5/3/22
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Greetings,

My understanding of reading the documents for LRMI is that many of the expected values include the data type "text". This appears to be defined as schema.org/Text.


However, my understanding is that there is no technical definition of what can or can not be included in schema.org/Text. For example, control characters, or a defined character set such as UTF-8 (as opposed to UTF-16 or latin-1). This seems to be a hole in the LRMI standard... at least for implementation purposes. See discussion here: https://github.com/schemaorg/schemaorg/issues/3033

Is my understanding correct?

- Hugh

Phil Barker

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May 4, 2022, 5:37:54 AM5/4/22
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On 03/05/2022 17:11, Hugh Paterson III wrote:

Greetings,

My understanding of reading the documents for LRMI is that many of the expected values include the data type "text". This appears to be defined as schema.org/Text.

Yes, that is true of the properties as adopted by schema.org, for example schema:educationalLevel. It is a feature of schema.org that the ranges are loosely defined and very often include Text. This is makes publishing data easier but consuming it harder than if the range were more tightly constrained, which is a schema.org design decision.

The same property is also defined in the Dublin Core LRMI namespace, as http://purl.org/dcx/lrmi-terms/educationalLevel, where the value is is expected to be a schema:DefinedTerm or a SKOS:Concept. This is arguably more suited to environments where there are greater expectations on the producers of metadata to conform to a standard in order to make it easier to consume that data.

In both cases the expected value type is defined using schema:rangeIncludes, which (intentionally) leaves enough leeway for us to say that the properties are the same (in RDF terms).

However, my understanding is that there is no technical definition of what can or can not be included in schema.org/Text. For example, control characters, or a defined character set such as UTF-8 (as opposed to UTF-16 or latin-1). This seems to be a hole in the LRMI standard... at least for implementation purposes. See discussion here: https://github.com/schemaorg/schemaorg/issues/3033

Is my understanding correct?

That is my understanding too.

I assume that when it comes to character sets such as UTF-8 etc, the character encoding would be set for the file as a whole, e.g. in the charset parameter of the HTTP header or as the "encoding" attribute in the xml header.

Phil


- Hugh
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