Invariant responding among individuals with autism spectrum disorder (ASD) is problematic and can be pervasive across all areas of development. Individuals with ASD demonstrate difficulty communicating wants and needs and often engage in challenging behavior in order to get needs met. Functional communication training (FCT) is one approach for mediating challenging behavior by teaching individuals a communicative response that is functionally equivalent to the demonstrated challenging behavior. However, individuals are often taught a single communicative response (e.g., vocal approximations) that may be unintelligible to the naïve listener and challenging behavior may resurge as a result of a communication breakdown. Recently, the evaluation of lag schedules of reinforcement has shown that it is possible to reinforce operant variability during instruction. Increasing communicative variability for individuals with ASD may decrease the likelihood of resurgence of challenging behavior by providing a broader repertoire of socially appropriate communicative responses that contacted reinforcement through the use of a lag schedule of reinforcement. The purpose of the present study was to evaluate the effect a lag schedule of reinforcement on communicative variability in three individuals with ASD. In this study, communication was reinforced on either a Lag 0 (or FR1 concurrent) schedule of reinforcement, or a Lag 1 (e.g., responses contacted reinforcement only if the response differed from the previous communicative response). Functional analyses were conducted for each participant to determine variables maintaining challenging behavior, all participants were given a mand topography assessment to evaluate mand topography proficiency, and a lag schedule evaluation was conducted. Results showed that increasing the lag schedule of reinforcement from Lag 0 to Lag 1 increased communicative mand topographies for all participants. Results further showed a significant reduction in challenging behavior as compared to baseline conditions contingent on implementation of the FCT package. / text

published_or_final_version / Medical Sciences / Master / Master of Medical Sciences

No description available.

The problem of finding a schedule with the lowest makespan in the class of all flowtime-optimal schedules for parallel identical machines is an NP-hard problem. Several approximation algorithms have been suggested for this problem. We focus on algorithms that are fast and easy to implement, rather than on more involved algorithms that might provide tighter approximation bounds. A set of approaches for proving conjectured bounds on performance ratios for such algorithms is outlined. These approaches are used to examine Coffman and Sethi's conjecture for a worst-case bound on the ratio of the makespan of the schedule generated by the LD algorithm to the makespan of the optimal schedule. A significant reduction is achieved in the size of a hypothesised minimal counterexample to this conjecture.

This dissertation consists of three essays examining the determinants of child developmental outcomes using the Canadian National Longitudinal Survey of Children and Youth (NLSCY). The first essay estimates the relationship between birth weight and cognitive and behavioral outcomes for children aged 0 to 13. Using family fixed effects models to control for household heterogeneity, I find that every ounce counts; additional birth weight for infants born weighing less than 2,500 grams (low birth weight infants) is related to better outcomes for measures of math ability, pro-social behavior and property offense. Additional birth weight for those born weighing 2,500 grams or more is related to higher scores of motor and social development and verbal competence for young children. The second essay, using a sample of Canadian boys and girls aged 10 to 15 in dual-earner families, finds that parental work schedules play an important role in adolescents’ engagement in risky behaviour, especially for boys. Non-standard parental work schedules (i.e. work during evenings, nights, weekends and rotating shifts) are positively related to fighting, drinking and trying drugs among boys and fighting among girls. In the third essay, I investigate relationships between symptoms of hyperactivity-inattention and being read to for a sample of children aged 2 to 4. The main finding, based on family fixed effects estimates, is that children who have higher hyperactivity-inattention are read to less. However, results from interactions suggest that this relationship is only present when the person most knowledgeable of the child (usually the biological mother) has less than a post-secondary degree or diploma.

Thesis (M.B.M. 1976) from the Department of Commerce, University of Adelaide.

Thesis (M.I.T.)--The Evergreen State College, 2007. / Title from title screen viewed (6/23/2008). Includes bibliographical references (leaves 98-100).

Thesis (Ed. D.)--Illinois State University, 1977. / Title from title page screen, viewed Dec. 17, 2004. Dissertation Committee: Creta Sabine (chair), Elwood Egelston, Ronald Laymon, Larry Kennedy, Ronald Halinski. Includes bibliographical references (leaves 110-115) and abstract. Also available in print.

Thesis (Ed. D.)--University of Missouri-Columbia, 2000. / Typescript. Vita. Includes bibliographical references (leaves 105-109). Also available on the Internet.

Thesis (Ed. D.)--Illinois State University, 1998. / Title from title page screen, viewed July 7, 2006. Dissertation Committee: Larry McNeal (chair), Kenneth Strand, Rodney Riegle, Joe Parks, Walter H. Warfield. Includes bibliographical references (leaves 98-103) and abstract. Also available in print.