Operator: Completed

Operator Overview:

All the implementation chunks of a u/s-constructor are not created in the same space. Those that are related to link, snip for a u-constructor and fuse, semsnip for a s-constructor or empty-op for both are built in the u-construct space and s-construct space, respectively. However, two important chunks are built in the problem space of this operator: one to reconsider the u/s-constructor and the other to mark the u/s-model-success flag on the current word. The application of this operator produces these two chunks.

Operator Proposal:

There are a set of different conditions for the proposal of a completed operator. The simplest one is when we have an empty operator as the u/s-constructor. It gets proposed also when we have a connected model, that is, the u/s-model is a tree instead of a forest (The completion space tests that the top-state has the attribute ^receivers-ids or ^semreceivers-ids. The value of this attribute is the root of a tree and it can only hold one value. If there is more than one tree, there will be an attribute impasse because all the values have no parallel preference and this attribute will disappear from working memory. At this point, the completion space will recognize this situation as incomplete).

The other two conditions for u-constructors are slightly more obscure. The first says that if we have just processed an NP and if there is an open-V1 (as in X-bar theory), then the model is complete. The second says that if there is a NP and there is an open-C1 then the model is also complete. Note that in the case when the u-model has more than a tree and either of the last two conditions is satisfied, the completed operator will still get selected over the incomplete operator because it is has a better preference. For s-constructors, obscure cases are those that are immediately marked s-model-success and so s-constructor is built at all. These are words such as determiners and copulas.

Operator Application:

Proposes the reconsider preference for the impassed u/s-constructor and marks u/s-model- success on the current word.

Operator Reconsider:

The completion problem space is a response to the operator no-change impasse of an u/s-constructor and hence, when the u/s-constructor gets a reconsider preference, the entire problem space disappears.

Back to the operator hierarchy.

This page written by Han Ming Ong (hanming@cs.cmu.edu)

Updated by Julie Van Dyke (vandyke@cs.cmu.edu), August, 1997