“…Many of these studies have done so indirectly prior to the study. For example, many researchers have conducted paired-stimulus (Fisher et al, 1992), free operant (Roane, Vollmer, Ringdahl, & Marcus, 1998), or multiple stimulus without replacement (DeLeon & Iwata, 1996) preference assessments to identify preferred stimuli to teach the participants to mand (Betz, Higbee, & Pollard, 2010;Bock et al, 2005;Bourret, Vollmer, & Rapp, 2004;Carr & Kologinsky, 1983;Davis, Kahng, & Coryat, 2012;Endicott & Higbee, 2007;Ganz, Simpson, & Corbin-Newsome, 2008;Gutierrez et al, 2007;Hartman & Klatt, 2005;Kodak & Clements, 2009;Kodak, Paden, & Dickes, 2012;Lechago et al, 2010;O'Reilly et al, 2012;Sidener et al, 2010;Tincani, 2004). Other researchers selected suspected reinforcers to teach individuals to mand by observing the individuals' reactions to those items or by measuring the amount of time the participants spent engaging with those items (Kelley et al, 2007;Lechago et al, 2010;Sweeney-Kerwin et al, 2007).…”