-ity: A study in word formation restrictions

Subjects judged the acceptability of pseudo words formed a stem, an optional affix, and-ity. The results show that those words in which-ity was adjacent to a latinate morpheme were more acceptable than those in which it was not. Other factors which influenced the acceptability ratings were familiarity and homogeneity of morpheme types. In their evaluations of the possible words, subjects were sensitive to historical class distinctions of stems and affixes.