The Ellsberg Paradox documented the aversion to ambiguity in the probability of winning a prize. Using an original sample of 266 business owners and managers facing risks from climate change, this paper documents the presence of departures from rationality in both directions. Both ambiguity-seeking behavior and ambiguity-averse behavior are evident. People exhibit âfearâ effects of ambiguity for small probabilities of suffering a loss and âhopeâ effects for large probabilities. Estimates of the crossover point from ambiguity aversion (fear) to ambiguity seeking (...) (hope) place this value between 0.3 and 0.7 for the risk per decade lotteries considered, with empirical estimates indicating a crossover mean risk of about 0.5. Attitudes toward the degree of ambiguity also reverse at the crossover point. (shrink)
Optimal protective responses to long-term risks depend on rational perceptions of ambiguous risks and uncertain time horizons. Our study examined the joint influence of uncertain delay and risk in an original sample of business owners and managers. We found that many subjects disliked uncertainty in the timing of an outcome, a reaction we term ``lottery timing risk aversion.'' Such aversion to uncertain timing was positively related to aversion to ambiguous probabilities for lotteries involving storm damage risks. This association suggests that (...) uncertainty may be processed similarly in both the risk and time dimensions. (shrink)
Fodor and Lepore, in their recent book "Holism," maintain that if an inference from semantic anatomism to semantic holism is allowed, certain fairly deleterious consequences follow. In Section 1 Fodor and Lepore's terminology is construed and amended where necessary with the result that the aforementioned deleterious consequences are neither so apparent nor straightforward as they had suggested. In Section 2 their "Argument A" is considered in some detail. In Section 3 their "argument attributed to Quine" is examined at length and (...) a shorter and more perspicacious argument suggested which avoids their charge that the Quinean argument is guilty of an equivocation on the word 'statement'. (shrink)
The word “philosophy” comes from the Greek “philos” (meaning love) and “sophia” (meaning wisdom); thus philosophy literally is the “love of wisdom.” Whatever else philosophy may be, most people agree that it still retains this spirit of its etymological roots, and that when we are engaged in philosophy we are pursuing wisdom for the sake of itself. Wisdom, however, is not the same thing as knowledge or information. We aren’t merely trying to amass list of interesting ideas, or believe anything (...) that sounds good. Wisdom is, at least in part, the reflection on and critical evaluation of what we ourselves and others around us believe about some very heady topics. (shrink)
After determining one set of skills that we hoped our students were learning in the introductory philosophy class at Carnegie Mellon University, we designed an experiment, performed twice over the course of two semesters, to test whether they were actually learning these skills. In addition, there were four different lectures of this course in the Spring of 2004, and five in the Fall of 2004; and the students of Lecturer I (in both semesters) were taught the material using argument diagrams (...) as a tool to aid understanding and critical evaluation, while the other students were taught using more traditional methods. We were interested in whether this tool would help the students develop the skills we hoped they would master in this course. In each lecture, the students were given a pre-test at the beginning of the semester, and a structurally identical post-test at the end. We determined that the students did develop the skills in which we were interested over the course of the semester. We also determined that the students who were able to construct argument diagrams gained significantly more than the other students. We conclude that learning how to construct argument diagrams improves a student's ability to analyze, comprehend, and evaluate arguments. (shrink)
There is substantial evidence from many domains that visual representations aid various forms of cognition. We aimed to determine whether visual representations of argument structure enhanced the acquisition and development of critical thinking skills within the context of an introductory philosophy course. We found a significant effect of the use of argument diagrams, and this effect was stable even when multiple plausible correlates were controlled for. These results suggest that natural and relatively minor modifications to standard critical thinking courses could (...) provide substantial increases in student learning and performance. (shrink)
Argument-mapping software abounds, and one of the reasons is that using the software has been shown to teach/promote/improve critical-thinking skills. These positive results are very encouraging, but they also raise the question of whether the computer tutorial environment is producing these results, or whether learning argument mapping, even with just paper and pencil, is sufficient. Based on the results of two empirical studies, I argue that the basic skill of being able to represent an argument diagrammatically plays an important role (...) in the improvement of critical-thinking skills. While these studies do not offer a direct comparison between the two methods, it is important for anyone wishing to employ argument mapping in the classroom to know that significant results can be obtained even with the most rudimentary of tools. (shrink)
Recently, Rueger and Sharp (1996) and Koperski (1998) have been concerned to show that certain procedural accounts of model confirmation are compromised by non‐linear dynamics. We suggest that the issues raised are better approached by considering whether chaotic data analysis methods allow for reliable inference from data. We provide a framework and an example of this approach.
After determining one set of skills that we hoped our students were learning in the introductory philosophy class at Carnegie Mellon University, we performed an experiment twice over the course of two semesters to test whether they were actually learning these skills. In addition, there were four different lectures of this course in the first semester, and five in the second; in each semester students in some lectures were taught the material using argument diagrams as a tool to aid understanding (...) and critical evaluation, while the other students were taught using more traditional methods. In each lecture, the students were given a pre-test at the beginning of the semester, and a structurally identical post-test at the end. We determined that the students did develop the skills in which we were interested over the course of the semester. We also determined that the students who were taught argument diagramming gained significantly more than the students who were not. We conclude that learning how to construct argument diagrams significantly improves a student’s ability to analyze arguments. (shrink)
Using historical data from the Utah Population Database, this analysis finds significant, consistent, but small adverse mortality effects for mothers after age 50 who had mostly sons. Examination of age-dependent effects indicates that this association increases with mother’s age. Additionally, mothers who had mostly daughters faced mortality risks that increased with age. Offspring sex composition did not have a significant effect on paternal mortality. Interaction analyses were conducted to examine the effect of offspring sex composition with regard to historical period, (...) residential location, socioeconomic status, and childhood survival. No other interactions were found to be statistically significant. Having mostly boys remained detrimental to maternal mortality regardless of childhood survival. (shrink)
Integrating a historical perspective into studies of prejudicial attitudes facilitates the interpretation of paradoxical findings of the kind cited in the target article. History also encourages research to move beyond the study of prejudice and to consider institutional and structural forces that maintain social inequities. Multilevel approaches can study these factors in both field and laboratory studies.
In opposing the legalization of physician-assisted suicide and voluntary euthanasia, Peter Harrell '02 in his April 3 column claims that the example of the Netherlands — so far the only country in the world where both of these practices take place openly and without fear of prosecution — shows that this would be a dangerous course to follow. But none of the evidence that he offers allows him to draw this conclusion.