Definitions for Actor, Object, Verb, Activity in xAPI-About.md

[alanepaull]

I found it slightly confusing that there's no definition of Object in the Definitions section (4.0), especially as an Object is referred to in the definition for Activity. It might be clearer if a definition of Object could be included.

Linked to this, the definitions for Actor and Verb are perhaps not tight enough?

Currently - Actor: An individual or group representation tracked using Statements performing an action within an Activity. Is the "I" in "I did this".

I don't think an Actor can perform an action within an Activity, because an Actor is a separate component from the Activity. It looks like "Activity" here is being used almost with its natural language meaning. With a definition of Object, the Actor definition could be refined to: Actor: An individual or group representation tracked using Statements performing an action on an Object. Is the "I" in "I did this". Or alternatively, using Activity instead of Object: Actor: An individual or group representation tracked using Statements performing an action in relation to an Activity. Is the "I" in "I did this".

Currently - Verb: Is the action being done by the Actor within the Activity within a Statement. A Verb represents the "did" in "I did this".

Again, the Actor isn't doing an action within the Activity. Could be refined to: Verb: Is the action being done by the Actor within a Statement. A Verb represents the "did" in "I did this".

Unless, of course, I'm entirely wrong about what an Activity is.

[andyjohnson]

Per the the 6/7/2017 call, we agree that some other term like "experience" or "interaction" is more accurate and we should be careful about using the word "Activity" unless we specifically mean an Object with type Activity. It is also possible to have a Statement without an "Activity" in this sense, where the Object could be an Actor. PR to follow.