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Last updated on:
21-May-2009
 
 
 
Unublished Results
This section contains research that has not been published and is not (or no longer) meant for publication. It includes findings from pilot studies, unpublishable null-findings, or modles for which data could not be obtained
[Why publish such findings?]
 
Trautmann, Stefan T., and Ferdinand M. Vieider (2007). Prenatal Screening Decisions: Information Seeking and Over-testing. Working Paper, Erasmus University Rotterdam
In laboratory tests about decision under uncertainty people are often found to suffer from ambiguity aversion, whereby they prefer crisp probabilities over equivalent vague probabilities. The irrationality of this phenomenon resides in the fact that people are ready to pay a premium for such crisp probabilities. We propose the concept of information seeking, an adaptation of ambiguity aversion that can be employed more easily in real-world applications, and want to test it on decisions about prenatal screening tests for Down syndrome. Screening tests provide updates on a mother’s base rate probability of giving birth to a child with Down syndrome. A positive screening test generally leads to a diagnostic test, an invasive procedure that involves a certain risk of losing the child. We hypothesize that some people will take screening tests even though their diagnostics decision is already clear beforehand, thus seeking probabilistic information that they are not planning to use. Also, we hypothesize that the uptake of screening tests will be independent of base rate probabilities, and available information is thus used sub-optimally. [The model in this paper was developed to be tested on a specific data-set. After one year of work on the model, the researchers who had the data changed their mind on granting us access to them.]
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Vieider, Ferdinand M. (2007). The Effect of Accountability on Risk Attitude: Probability Weighting, Utility Curvature, and Loss Aversion. Working Paper, Haas School of Business, University of California at Berkeley
This paper investigates the effect of accountability – the explicit or implicit expectations of having to justify one’s decisions to somebody else – on risk attitude. Risk attitude is thereby divided into its three main components – utility curvature, probability weighting, and loss aversion. While no effect is found for risk attitude in the gain domain, a strong effect is detected for loss aversion. Loss aversion is thereby found to be reduced when subjects are accountable. This effect is explained by the higher cognitive effort induced by accountability, which triggers a rational check on emotional reactions at the base of loss aversion, leading to a reduction of the latter. Connections to dual processing theories are discussed. [Original paper from which the Acta publication, Vieider (2009), has been derived. In addition to the publication, this version contains to non-significant experiments about effects of accountability on risk aversion which have been removed from the published version.]
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Vieider, Ferdinand M. (2007). Anchoring and Adjustment under Accountability: some unpublished data and a small meta-analysis
Some non-significant results testing the effect of accountability on anchoring and adjustment are presented. These results are then combined with existing data in a meta- analytic way to show that the combined results point strongly in the direction that accountability increases adjustment. Finally, some issues in and consequences for the (presumed) difference between externally provided and internally generated anchors are discussed. [Results presented stem from a pilot study carried out in a class room. The purpose of the study was to define tasks for future experiments.]
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