Graduate Thesis Or Dissertation

The role of scientific thinking in environmental policy decisions

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  • The purpose of this study was to analyze the individual reasoning of 24 adults as they made decisions for two communities regarding municipal wastewater treatment. The two western Oregon communities were both responding to notices from governmental agencies of higher environmental standards for the purification of wastewater before it could be returned to local streams. Both cities considered the possibility of integrating this relatively unproven method into their existing conventional treatment systems. There were differing opinions within both groups about the use of "green treatment" technology. For the group decisions City B rejected the idea and City A opted to try a small pilot project. The focus of this study was not on the outcome of the group decisions, but on the individual reasoning of each subject. Each of these people was asked to rate 20 statements about constructed wetlands using a 4 point scale to measure his/her initial core beliefs (ICB) in the context of this study. The range of possible scores was from -40 to +40, but the scores of the 24 subjects in this study ranged from +2 to +39. It was assumed that a person with a low ICB score had a lower interest in using constructed wetlands for water purification than a person with a higher ICB score. Each subject was asked to verbally describe his/her reasoning in regard to his/her respective group decision in a face to face interview. The interviews were designed to allow each subject to respond to questions about his/her personal content knowledge, decision commitment and alternative epistemology regarding the "green treatment" concept of water purification. The rhetorical arguments of each subject were audio-taped and transcribed. The data were qualitatively analyzed for critical thinking operations (CTO) and fallacious thinking patterns (FTP). A regression analysis showed a correlation coefficient for these features of -0.70. Nine of the subjects exhibited zero FTP in their reasoning. Those nine subjects scored within the interquartile range of the group distribution of ICB scores. Of the 15 subjects with FTPs identified in their reasoning, only two had ICB scores within the interquartiles, and the remaining 13 had ICB scores in either the upper or lower quartiles of the group distribution. This pattern suggests that a person with strong bias for or against the constructed wetland concept is more apt to make errors in reasoning than is a person with a moderate view of the issue.
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