“…Investigations of the properties of demands that establish escape motivation are limited. However, investigators have identified a number of dimensions that are salient in one or more cases, including task difficulty (Carr & Durand, 1985a;Weeks & Gaylord-Ross, 1981), type of required motor responses (Dunlap, KernDunlap, Clarke, & Robbins, 1991), number of required responses (Mace, Browder, & Lin, 1987), task novelty (Mace et al, 1987), duration of instructional sessions (Dunlap et al, 1991), rate of task presentation (Smith, Iwata, Goh, & Shore, 1995), unpredictability of events (Flannery & Horner, 1994), and task preference (Dunlap et al, 1991;Foster-Johnson, Ferro, & Dunlap, 1994). In addition, the probability of problem behavior following a particular demand may be reduced by prior or interspersed events such as storytelling (Carr, Newsom, & Binkoff, 1976), social comments (Kennedy, Itkonen, & Lindquist, 1995), demands highly likely to be complied with (Mace & Belfiore, 1990), and advance notification (Tustin, 1995).…”