INTRODUCTION

This chapter introduces a theoretical framework that describes the importance of affect in guiding judgments and decisions. As used here, affect means the specific quality of goodness or badness (a) experienced as a feeling state (with or without consciousness) and (b) demarcating a positive or negative quality of a stimulus. Affective responses occur rapidly and automatically – note how quickly you sense the feelings associated with the stimulus word “treasure” or the word “hate.” We shall argue that reliance on such feelings can be characterized as the affect heuristic. In this chapter we trace the development of the affect heuristic across a variety of research paths followed by ourselves and many others. We also discuss some of the important practical implications resulting from ways that this heuristic affects our daily lives.

BACKGROUND

Although affect has long played a key role in many behavioral theories, it has rarely been recognized as an important component of human judgment and decision making. Perhaps befitting its rationalistic origins, the main focus of descriptive decision research has been cognitive, rather than affective. When principles of utility maximization appeared to be descriptively inadequate, Simon (1956) oriented the field toward problem-solving and information-processing models based on bounded rationality. The work of Tversky and Kahneman (1974; Kahneman, Slovic, & Tversky, 1982) demonstrated how boundedly rational individuals employ heuristics such as availability, representativeness, and anchoring and adjustment to make judgments and how they use simplified strategies such as elimination by aspects to make choices (Tversky, 1972).