eml questions

[Matt Jones]

Hi Eda,

Nice to hear from you.  Here's my perspective on your questions:

Eda Melendez wrote:
> Dear Matt:
> 
> I really don't know if I should be bothering you with this but I want to go to 
> a primary source, the originator, and skip any possible misinterpretations of 
> what the EML module "eml-attribute" entails.
> 
> I am just mapping my metadata concerning the attributes(my variables) and my 
> serious doubt is when I get to your required "measurementScale" field.
> 
> Looking it from my point of view, I interpret its elements as follows. Please 
> tell me if I am wrong or clarify what I don't understand:
> 
> If I have a text field (alphanumeric), it is nominal with a textDomain (but 
> then I need a definition and I might not have any...so it is really nominal 
> type? what if not?)

Nominal fields include any fields whose values are unordered and are 
restricted to a finite list (an enumeration) or a free text value.

If your field can contain any text (e.g., a comment field), it is 
nominal, you still need to provide a definition of the field, and set 
the domain to "textDomain".  Under text domain you can optionally 
provide a pattern that restricts the text values that are allowed (e.g., 
you could provide a regular expression filter that only allows text 
values that are all capital letters), but you don't have to.  If you 
omit the optional pattern, by default any text string of any length is 
allowed in the field.

> If I have a field with codes that are not numeric (eg., C=control, F= 
> fertilized, L=litter removed) it is also nominal with textDomian (...what do 
> you mean by "enumeratedDomain"?). I have here text but need to do a Code-
> Definition duplet for each one.

The word "enumeration" can be loosely defined as a "discrete list of 
items", and so an "enumeratedDomain" is a domain consisting of a finte 
list of items.  If the values of your field are restricted to a finite 
list but are not ordered, then it is an enumeration and is nominal type 
with a domain of "enumeratedDomain".  Within the "enumeratedDomain field 
you list each allowed value (code) along with its definition (or provide 
a reference to those codes and definitions if they are defined 
elsewhere, although this isn't as good because it might not always be 
available at the external source).

> 
> If I have a field with codes that are integers and represent a class...with 
> some kind of logical order (eg., 1 = 1-25% cover, 2= 25-50% cover, ans so on) 
> is ordinal and I'm happy beacause I have an enumeratedDomain with a Code-
> Definition duplet; If the codes have no order (your example of male and female) 
> then the attribute measurementScale will be nominal with an enumeratedDomain 
> and I will still be happy because I got my duplet again.

right.

> If I have a field that measures lenghts, or counts things is ratio with a unit 
> (standard or costum), precision and numericDomain(numberType).

right.

> Thanks and I hope my confusion does not annoy you (it certainly annoys me).
> 
> EDA


Happy to help anytime,

Matt