Effects of time pressure on human judgments and decision making

Sammanfattning: The main purpose of this thesis was to examine effects of time pressure on human decisions and judgments. Earlier findings suggested that people cope with time restrictions by focusing on more central parts of the information and that higher priority was given to negative information to avoid negative consequences. This line of research was followed up in four empirical studies with a structural approach and static decision tasks. Thus, all information about the decision alternatives was given at the same time for each decision problem. Subjects' choices and judgments were studied in relation to the applicability of different decision rules, with and without a strict time limit. The main variations between the empirical investigations are the number of alternatives given in a decision problem and the amount of information that describes the alternatives (incomplete versus complete). The four empirical studies showed that people change their decision behavior when decisions and judgments have to be made under time pressure. In particular, positive information about alternatives becomes more important. These findings contradict earlier results which emphasized the greater role of negative information under time pressure. The present results provide empirical evidence that people can cope with time pressure by focusing on the most important information indicating filtration and support for the applicability of a kind of lexicographic decision rule. This holds when the decisions were made among three alternatives and when the alternatives were close in attractiveness. When there was incomplete information about the alternatives there was a change towards more support to the most attractive aspect rule. Thus, there seems to be a search for the most positive aspect overall attributes. In sum, the present thesis has found support for that time pressure has the effect of focusing on the most important attribute and giving more priority to positive information in a decision task.