Case agreement on noun adjuncts
A noun adjunct (also termed attributive noun) is a noun, other than the head noun, that appears in a noun phrase and modifies the head as an attribute.1 Depending on the language, it may or may not show agreement with the head noun in terms of number and case. This should be determined by considering oblique cases.2
Types:
NoCase: There is no case system.
NoNXCaseAgr: There is no case agreement between head nouns and their adjuncts in general.
NoNNCaseAgr: Case agreement exists, but it does not apply in the case of head nouns and their noun adjuncts.
NNCase~Agr: Case agreement exists, but the grammatical form of the noun adjunct is (somewhat) different from that of the head noun (partial agreement).3
NNCaseAgr: The noun adjunct displays the same grammatical form as that of the head noun (total agreement).
When a language displays more than one type, multiple values can be listed. If one type is dominant, a slash (/) can separate the two values, with the dominant value appearing first; if neither is dominant, they are listed with a plus sign (+) separating the two. The listing of multiple values should be explained in the commentary.
1: Examples include My friend the engineer, Principal John Smith, and Fido the dog.
2: Oblique cases may include the locative, lative, instrumental, and comitative.
3: To be detailed in the commentary