Date of Award:


Document Type:


Degree Name:

Doctor of Philosophy (PhD)



Committee Chair(s)

Amy L. Odum


Amy L. Odum


Kerry E. Jordan


Gregory J. Madden


Timothy A. Shahan


Timothy A. Slocum


Delay discounting is the process by which delayed outcomes lose value. Different types of delayed outcomes (e.g., food and money) lose value to different degrees. Higher degrees of delay discounting are related to a wide variety of psychosocial maladies. Chapter I provides context for the studies described in Chapters II-IV. Specifically, cigarette smokers routinely discount delayed money to a greater degree than nonsmokers. Chapters II and III explore the generality of the relation between cigarette smoking and delay discounting by examining how different types of delayed outcomes are discounted. The data presented in these chapters indicate that smokers show a pervasive tendency to steeply discount various types of outcomes when compared to nonsmokers. Across both smokers and nonsmokers, the degree to which a person discounts one delayed outcome is correlated with how they will discount other outcomes. The additive utility model is a recently proposed model of delay discounting that provides potential mechanisms of delay discounting to explain the findings of Chapters II and III. Chapter IV describes the results of empirical test of the additive utility model as it relates to qualitatively different delayed outcomes. In this study, the additive utility model described delay discounting data as well as a more standard model of delay discounting, the hyperbolic model. This study provides tentative support for the additive utility model of delay discounting as an explanatory model. Finally, Chapter V provides a summary of all three studies.