Economy in PF Reduction: Why and When (Not) to Elide Multidominant Structures

Multidominant structures and structures containing ellipsis both result in PF reduced representations: representations in which some material is interpreted but not pronounced. Focusing on two such PF reduced constructions, coordinated wh-questions and coordinated sluices, we argue that PF reduction is subject to economy, which favors “least effort” derivations and bans vacuous operations. We argue that, everything else being equal, structures containing multidominance are favored by economy compared with structures containing ellipsis. We also show that economy forces different structures for coordinated wh-questions and coordinated sluices, which is why these two constructions have different properties.