Study 1.3

The third study served to further analyze the structure of causal knowledge about global change and to investigate the relationship between the causal structure and risk evaluation on psychometric scales. We distinguished five causal levels of global environmental risks: a) people`s attitudes, e.g., laziness, b) human activities, e.g., car driving, c) pollution / emission, e.g., air pollution or CO2-emission, d) environmental changes produced by this pollution or emission, e.g., enhancement of the greenhouse effect, and e) negative, usually long-term, consequences that affect human health and living conditions or the natural environment, e.g., loss of habitat.

Method

One hundred and fifty subjects participated in this study. Twenty-five environmental topics were presented to subjects. These topics were selected so that they covered the relevant issues pertaining to the two themes global warming and ozone depletion, and corresponded to the above mentioned five causal levels. Subjects performed two types of judgmental task. One task consisted of an evaluation of each topic on 13 judgment scales that were adapted from the psychometric paradigm. The other task consisted of causal judgments. Subjects were asked to indicate the most important cause of each topic and its most important consequence. The cause and consequence of each topic were to be selected from the very same list of the 25 environmental topics.

Results

Multivariate analyses reveal that the causal scenarios derived from the causal judgments are systematically related to differences in their risk evaluation on the psychometric scales. A classification of the topics based on the causal ascription task reproduces the five causal levels, which in turn differ with respect to their risk evaluation. Graph-theoretical network analyses of the causal judgments show that the ascription patterns for causes differ from those for consequences. Whereas subjects tend to select immediate rather than mediated causes, they generally ascribe negative consequences for humans, even if those consequences are mediated by extended causal chains.