His research interests include the formal development and validation of expert systems.

Two experiments investigated whether judgments of happiness and satisfaction with one's life are influenced by mood at the time of judgment. In Experiment 1, moods were induced by asking for vivid descriptions of a recent happy or sad event in respondents' lives; in Experiment 2, moods were induced by interviewing participants on sunny or rainy days. In both experiments, subjects reported more happiness and satisfaction with their life as a whole when in a good mood than when in a bad mood. However, the negative impact of bad moods was eliminated when subjects were induced to attribute their present feelings to transient external sources, irrelevant to the evaluation of their lives. Subjects who were in a good mood, on the other hand, were not affected by misattribution manipulations. The data suggest (a) that people use their momentary affective states as information in making judgments of how happy and satisfied they are with their lives in general and (b) that people in unpleasant affective states are more likely to search for and use information to explain their state than are people in pleasant affective states. Thus the data demonstrate informative and directive functions of affective states.

This review organizes a variety of phenomena related to emotional self-report. In doing so, the authors offer an accessibility model that specifies the types of factors that contribute to emotional self-reports under different reporting conditions. One important distinction is between emotion, which is episodic, experiential, and contextual, and beliefs about emotion, which are semantic, conceptual, and decontextualized. This distinction is important in understanding the discrepancies that often occur when people are asked to report on feelings they are currently experiencing versus those that they are not currently experiencing. The accessibility model provides an organizing framework for understanding self-reports of emotion and suggests some new directions for research.

How, and for whom, does disgust influence moral judgment? In four experiments participants made moral judgments while experiencing extraneous feelings of disgust. Disgust was induced in Experiment 1 by exposure to a bad smell, in Experiment 2 by working in a disgusting room, in Experiment 3 by recalling a physically disgusting experience, and in Experiment 4 through a video induction. In each case, the results showed that disgust can increase the severity of moral judgments relative to controls. Experiment 4 found that disgust had a different effect on moral judgment than did sadness. In addition, Experiments 2-4 showed that the role of disgust in severity of moral judgments depends on participants' sensitivity to their own bodily sensations. Taken together, these data indicate the importance-and specificity-of gut feelings in moral judgments.

Two experiments employed image-based tasks to test the hypothesis that happier moods promote a greater focus on the forest and sadder moods a greater focus on the trees. The hypothesis was based on the idea that in task situations, affective cues may be experienced as task-relevant information, which then influences global versus local attention. Using a serial-reproduction paradigm, Experiment 1 showed that individuals in sad moods were less likely than those in happier moods to use an accessible global concept to guide attempts to reproduce a drawing from memory. Experiment 2 investigated the same hypothesis by assessing the use of global and local attributes to classify geometricfigures. As predicted, individuals in sad moods were less likely than those in happier moods to classify figures on the basis of globalfeatures.

Three studies involving 3 participant samples (Ns = 39, 55, and 53) tested the hypothesis that people retrieve episodic emotion knowledge when reporting on their emotions over short (e.g., last few hours) time frames, but that they retrieve semantic emotion knowledge when reporting on their emotions over long (e.g., last few months) time frames. Support for 2 distinct judgment strategies was based on judgment latencies (Studies 1 and 2) and priming paradigms (Studies 2 and 3). The authors suggest that self-reports of emotion over short versus long time frames assess qualitatively different sources of self-knowledge.

Being happy or sad influences the content and style of thought. One explanation is that affect serves as information about the value of whatever comes to mind. Thus, when a person makes evaluative judgments or engages in a task, positive affect can enhance evaluations and empower potential responses. Rather than affect itself, the information conveyed by affect is crucial. Tests of the hypothesis find that affective influences can be made to disappear by changing the source to which the affect is attributed. In tasks, positive affect validates and negative affect invalidates accessible cognitions, leading to relational processing and item-specific processing, respectively. Positive affect is found to promote, and negative affect to inhibit, many textbook phenomena from cognitive psychology.

The authors tested whether happy moods increase, and sad moods decrease, reliance on general knowledge structures. Participants in happy, neutral, or sad moods listened to a "going-out-for-dinner" story. Happy participants made more intrusion errors in recognition than did sad participants , with neutral mood participants falling in between (Experiments 1 and 2). Happy participants outperformed sad ones when they performed a secondary task while listening to the story (Experiment 2), but only when the amount of script-inconsistent information was small (Experiment 3). This pattern of findings indicates higher reliance on general knowledge structures under happy rather than sad moods. It is incompatible with the assumption that happy moods decrease either cognitive capacity or processing motivation in general, which would predict impaired secondary-task performance.