The same is true of Weinstein 1989, which presents a short, pithy summary of unrealistic optimism research. This article is intended for an educated audience but one without specific background in optimism research. 2009 offers a review that focuses on continuing issues and controversies in optimism and pessimism research. Peterson 2000 provides some historical context and cautionary notes for contemporary optimism researchers. Carver and Scheier 2009 is a concise review of research on dispositional optimism as an individual difference variable, written by those responsible for development of the most frequently used measure of optimism and much of the most influential research on that construct. This volume includes chapters by virtually every major researcher in the area, as well as informative overview and summary chapters and chapters on the philosophical roots of modern views. Chang 2001 provides the most comprehensive collection of work on optimism/pessimism constructs. Psychologists have defined a variety of different kinds of optimism and pessimism, and few reference sources treat all of them. Thus, there will be some discussion of the construct and its measurement but only a few references to specific research results. There is an extensive research literature on attributional optimism, but the multidimensional nature of attributional styles and their weak relationship to other kinds of optimism/pessimism make extensive integration of that work with other optimism research beyond the scope of this article. Dispositional and attributional optimism/pessimism are not strongly correlated, and attributional optimism/pessimism focus on explanations of past events rather than expectations about the future. Those with an optimistic style explain negative events in terms of external, variable, and specific causes, while those with a pessimistic style use explanations that focus on internal, stable, and global causes. Explanatory or attributional styles, which refer to characteristic ways that people explain events, are often described as optimistic or pessimistic (or referred to as optimism or pessimism). Ongoing research investigates the relations among different kinds of optimism/pessimism, the potential independence of optimism and pessimism, and the specific processes by which they influence and are influenced by other constructs. There is also research on defensive pessimism, strategic optimism, hopeless pessimism, and situated (or situation-specific) optimism, as well as related concepts such as hope and illusion of control. Unrealistic optimism is positively related to dispositional optimism but often shows different relationships to outcomes. There is a large research literature on unrealistic optimism, which is sometimes referred to as “comparative” optimism, because it is defined as being more optimistic about one’s own future outcomes than about others’ future outcomes.

There are several other psychological concepts also labeled optimism and pessimism.

Dispositional optimists typically show more persistence and approach-focused ways of coping with short- and long-term stressors. Dispositional optimism is associated with a wide variety of positive outcomes, including better mental and physical health, motivation, performance, and personal relationships. Early interest in dispositional optimism/pessimism arose from its role in self-regulation models, because our expectations drive our responses during goal pursuit, especially when we encounter obstacles. Dispositional optimism/pessimism refer to broad, stable individual differences that are influenced by interactions between environment and genetics. In psychology, the most commonly used optimism/pessimism construct is dispositional optimism, which is the general tendency to expect positive outcomes, as opposed to dispositional pessimism, which is the general tendency to expect negative outcomes.