On the necessity of alignment: reply to Costello and Keane (2001).

In their article, "Testing two theories of conceptual combination: Alignment versus diagnosticity in the comprehension and production of combined concepts," F. J. Costello and M. T. Keane (2001) evaluate the role of alignment in the interpretation of noun-noun combinations. They found that participants were not strongly biased to prefer and produce interpretations with alignable differences. Instead, participants sometimes preferred and produced interpretations with nonalignable differences. These results are surprising given that most research has found advantages of alignable differences over nonalignable differences. Costello and Keane also found that feature diagnosticity better predicted their results, and they concluded that alignment does not play an important role in conceptual combination. However, drawing on recent work, the author of the present article gives an alternative interpretation of Costello and Keane's results, showing that alignment is crucial in conceptual combination. The author also shows that the dual-process model accounts for their results.