How does preference reversal appear and disappear? Effects of the evaluation mode

Preference reversal is a systematic change in the preference order between options when different response methods are used (e.g., choice vs. judgment). The present study focuses on procedures used to elicit preferences according to an evaluability hypothesis. Two experiments compared joint vs. separate evaluations and explicit vs. non‐explicit joint evaluations. Subjects had to express preferences between high‐variance gambles (HVGs) and low‐variance gambles (LVGs) either by choosing one gamble to play in a lottery or by assigning gambles minimum selling prices. We show that HVGs are preferred in both choice and pricing conditions when gambles are evaluated separately, and LVGs are preferred in both choice and selling conditions when gambles are evaluated in pairs: i.e., when the evaluation mode is held constant, classic preference reversal disappears. These results support the evaluability hypothesis, and suggest that preferences depend on whether subjects are allowed to compare the options they are asked to choose from or judge, independently of the nature of the scale (i.e., attractiveness vs. minimum selling price) they are required to adopt. Copyright © 2004 John Wiley & Sons, Ltd.     

Spontaneous Eye Blink Rates vary according to individual differences in generalized control perception

This study tested the hypothesis that individual differences in generalized control perception for 43 undergraduate adults may be reflected in Spontaneous Eye Blink Rates during conversation in an interview. Control perception was assessed by means of Rotter's internal-external Locus of Control questionnaires, while Spontaneous Eye Blink Rates were computed from filmed videos of interviews consisting of a series of questions which could presumably have triggered different mental states. Pearson correlations and linear regression analyses indicated that the individual differences in Spontaneous Eye Blink Rates did not differ significantly across different questions, but that Spontaneous Eye Blink Rates measured over the entire interview correlated positively and significantly with an internal Locus of Control (r = .26). This could be interpreted as modest but corroborative evidence that a personality trait reflecting control perception may have a biological component. The possible roles of dopamine neurotransmission and frontal cortex involvement in higher cognition and Locus of Control are discussed.     

Discontinuous precipitation initiated at interphase boundaries in a Zn-rich Zn-6.3 at.% Ag alloy

Discontinuous precipitation in a two-phase Zn-rich Zn-6.3at.%Ag alloy has been studied. It has been shown that the eta/epsilon interphase boundaries have the ability to initiate discontinuous precipitation as do the eta/eta grain boundaries. The back-polishing method is used to show the interconnection between a discontinuous precipitate colony and the eta/epsilon interphase boundary. The reaction front velocity of discontinuous precipitation initiated at the eta/eta grain boundary is 12-90% higher than that of discontinuous precipitation initiated at the eta/epsilon interphase boundary under various ageing temperatures.