Decisions and Judgments in Ambiguous Situations: A Conceptual Introduction to Signal Detection Theory

There are times when we are unsure as to whether or not an event has  actually occurred. When stimuli or events are ambiguous, what governs  saying “yes” it is there or “no” it is not? Is that smile meant for us?  Is that shadow on the x-ray a tumor? Are there people here I’m  unprepared to meet? If I try, will I succeed? Is it SD or is it S∆? What  governs our behavior in these situations? Decisions and Judgments in  Ambiguous Situations reveals important variables that years of  laboratory and applied work have demonstrated to contribute to our  understanding of these complex relations through the lens of Signal  Detection Theory (SDT). SDT was developed to describe behavior where  stimuli to which we need to respond are embedded in “noisy”  environments, where there is uncertainty rather than clarity.

Readers  are taken through exercises in guided enquiry that introduces them to  some of the key variables that influence our decisions in ambiguous  situations. Each exercise is designed to be challenging yet easily  mastered. Readers are introduced to the concepts of signal and noise,  the role of consequences in a payoff matrix, response bias,  discriminability (sensitivity), decision rules, and the effects of the a  priori probability that an event will occur on our judgments. As one of  the foundations of nonlinear contingency analysis, readers will learn  that being “wrong” at times can be precisely what should be done, and  that optimal patterns of correct and incorrect responding can change for  the exact same stimulus presentations. Whereas introductions to SDT  often involve complex mathematics, this one does not. Little math,  outside of addition and division, is required. Upon completion of the  book, readers will have a good grasp of the underlying concepts and will  be able to apply them, including the ability to design and conduct SDT  experiments. It is a must read for any student of behavior analysis who  wants to extend their repertoire beyond simple ABC analysis and to  understand more complex behavioral relations.