Prof. Dr. Thomas Mussweiler

Research Priorities: Social cognition, judgement and decision-making processes, comparative processes, self-assessment, anchoring effects
Thomas Mussweiler is a German social psychologist. The psychological foundations of human judgement and decision-making processes make up the core of his research. His focus lies on the dynamics of comparative processes. Mussweiler developed the “selective accessibility model”, SAM, with which judgement, decision making, and comparative processes can be explained. His model and his work have been applied in a variety of areas.
As soon as humans judge other humans, themselves or objects, they do so using comparison. For a long time, the processes underlying these comparisons were insufficiently understood. Mussweiler’s research has contributed significantly to the theoretical and empirical understanding of these processes. The social psychologist developed an integrative model to explain comparative processes which he was able to test empirically. Thomas Mussweiler investigates the psychological dynamics of comparative processes, in particular in two contexts: self-assessment and decision making.
In the context of self-assessment, the answer to a question such as “How athletic am I?” depends on whether the standard of athleticism is an elite athlete or an unathletic relative. Thomas Mussweiler’s research shows that people tend to concentrate on similarities they have with the standard of comparison. The extent to which comparisons with others are used for personal decisions is also a question of cultural conventions. There are clear differences between more individualistic cultures and those, who are more collectivist.
Comparisons are also central to the behaviour surrounding decision making. Using the example of the “anchor effect”, Mussweiler’s research shows that human decisions are often influenced by numerical standards of comparison (“anchors”), even when these standards are irrelevant. This influence is typically subconscious and can lead to errors in reasoning.
Research into the “anchor effect” has important implications for various areas of application: In legal psychology, for example, it can explain unwanted influences on judges’ sentencing decisions. In negotiation research, it explains the great importance of the first bids in price negotiations, on which all subsequent bids are oriented.
In his other research, Mussweiler has investigated the topic “trust and distrust in everyday situations”, something about which, despite its relevance, relatively little is known. Base markers for individual positions in regards to trust were determined to include openness, willingness to cooperate, and orientation on social values.