Coordination (linguistics) - The Structure of Coordination

The Structure of Coordination

Theoretical accounts of coordination vary in major respects. For instance, constituency- and dependency-based approaches to coordination differ significantly, and derivational and representational systems are also likely to disagree on many aspects of how coordination should be explained, derivational accounts, for instance, being more likely to assume transformational mechanisms to "rectify" non-constituent conjuncts (e.g. conjunction reduction and RNR, as mentioned above).

Even concerning the hierarchical structure of coordinated strings, there is much disagreement. Whether or not coordinate structures should be analyzed in terms of the basic tree conventions employed for subordination is an issue that divides experts. Broadly speaking, there are two options: either a flat or a layered analysis. There are two possibilities for the flat option, both of which are shown here. The a-trees represent the analyses in a constituency-based system, and the b-trees in a dependency-based system:

The first two trees present the traditional exocentric analysis. The coordinate structure is deemed exocentric insofar as neither conjunct can be taken to be the sole head, but rather both conjuncts are deemed heads in a sense. The second two trees, where the coordinator is the head, are similar to the first two insofar as the conjuncts are equi-level sisters. These two flat analyses stand in contrast to the following three layered analyses. The constituency-based a-trees appear again on the left, and the dependency-based b-trees on the right:

The primary aspect of these layered analyses is that an attempt is being made to adapt the analysis of coordinate structures to the analysis of subordinate structures. The conjuncts in each case are NOT sister constituents, but rather the first conjunct is in a more prominent (higher) hierarchical position than the second conjunct. The three analyses differ with respect to the presumed head of the entire structure. The third option in terms of the X-bar schema cannot be rendered in terms of dependency because dependency allows a word to project just a single node. There is no way to capture the hierarchical distinction between specifiers and complements in a dependency-based system (but there is always a linear distinction, since specifiers precede complements).

The flat analysis has the benefit that it captures our intuition that coordinate structures are different from subordinate structures at a basic level. The drawback to the flat analysis, however, is that the theory of syntax must be augmented beyond what is necessary for standard subordinate structures. The layered analysis has the advantage that there is no need to augment the syntax with an additional principle of organization, but it has the disadvantage that it does not sufficiently accommodate our intuition that coordination is fundamentally different from subordination. Most if not all of the nine analyses just presented have been proposed in the massive body of literature on coordination.