Revealed Preference and Choice under Uncertainty

We employ the theory of rational choice to examine whether observable choices from feasible sets of prospects can be generated by the optimization of some underlying decision criterion under uncertainty. Rather than focusing on a specific theory of choice, our objective is to formulate a general approach that is designed to cover the various decision criteria that have been proposed in the literature. We use a mild dominance property to define a class of suitable choice criteria. In addition to rationalizability per se, we characterize transitive and Suzumura consistent rationalizability in the presence of dominance.

Strategy-proof preference aggregation

An aggregation rule maps each profile of individual strict preference orderings over a set of alternatives into a social ordering over that set. We call such a rule strategyproof if misreporting one’s preference never produces a social ordering that is strictly between the original ordering and one’s own preference. After describing a few examples of manipulable rules, we study in some detail three classes of strategy-proof rules: (i)rules based on a monotonic alteration of the majority relation generated by the preference profile; (ii)rules improving upon a fixed status-quo; and (iii) rules generalizing the Condorcet-Kemeny aggregation method.

Sustainability and Consumer Preference of Wild Caught Ornamental Fishes from Kerala: Scope of Certification

The Indian ornamental fish industry is divided into two-the domestic market and the export market. 90% of the freshwater ornamental fish exported from India are wild caught indigenous species. The study formed the criteria and indicators assessing the sustainability of wild caught ornamental fish exported from India. These indicators were then analyzed for their interactions, connections, linkages and relationships using cognitive mapping. The work is first of its kind in the ornamental fisheries

Left preference for sport tasks does not necessarily indicate left-handedness

In the elite domain of interactive sports, athletes who demonstrate a left preference (e.g., holding a weapon with the left hand in fencing or boxing in a ‘southpaw’ stance) seem overrepresented. Such excess indicates a performance advantage and was also interpreted as evidence in favour of frequency-dependent selection mechanisms to explain the maintenance of left-handedness in humans. To test for an overrepresentation, the incidence of athletes’ lateral preferences is typically compared with an expected ratio of left- to right-handedness in the normal population. However, the normal population reference values did not always relate to the sport-specific tasks of interest, which may limit the validity of reports of an excess of ‘left-oriented’ athletes. Here we sought to determine lateral preferences for various sport-specific tasks (e.g., baseball batting, boxing) in the normal population and to examine the relationship between these preferences and handedness. To this end, we asked 903 participants to indicate their lateral preferences for sport-specific and common tasks using a paper-based questionnaire. Lateral preferences varied considerably across the different sport tasks and we found high variation in the relationship between those preferences and handedness. In contrast to unimanual tasks (e.g., fencing or throwing), for bimanually controlled actions such as baseball batting, shooting in ice hockey or boxing the incidence of left preferences was considerably higher than expected from the proportion of left-handedness in the normal population and the relationship with handedness was relatively low. We conclude that (i) task-specific reference values are mandatory for reliably testing for an excess of athletes with a left preference, (ii) the term ‘handedness’ should be more cautiously used within the context of sport-related laterality research and (iii) observation of lateral preferences in sports may be of limited suitability for the verification of evolutionary theories of handedness.

Group preference structures in AHP–group decision making

This paper presents a procedure that allows us to determine the preference structures (PS) associated to each of the different groups of actors that can be identified in a group decision making problem with a large number of individuals. To that end, it makes use of the Analytic Hierarchy Process (AHP) (Saaty, 1980) as the technique to solve discrete multicriteria decision making problems. This technique permits the resolution of multicriteria, multienvironment and multiactor problems in which subjective aspects and uncertainty have been incorporated into the model, constructing ratio scales corresponding to the priorities relative to the elements being compared, normalised in a distributive manner (wi = 1). On the basis of the individuals’ priorities we identify different clusters for the decision makers and, for each of these, the associated preference structure using, to that end, tools analogous to those of Multidimensional Scaling. The resulting PS will be employed to extract knowledge for the subsequent negotiation processes and, should it be necessary, to determine the relative importance of the alternatives being compared using anyone of the existing procedures

On the exhaustiveness of truncation and dropping strategies in many-to-many matching markets

We consider two–sided many–to–many matching markets in which each worker may work for multiple firms and each firm may hire multiple workers. We study individual and group manipulations in centralized markets that employ (pairwise) stable mechanisms and that require participants to submit rank order lists of agents on the other side of the market. We are interested in simple preference manipulations that have been reported and studied in empirical and theoretical work: truncation strategies, which are the lists obtained by removing a tail of least preferred partners from a preference list, and the more general dropping strategies, which are the lists obtained by only removing partners from a preference list (i.e., no reshuffling). We study when truncation / dropping strategies are exhaustive for a group of agents on the same side of the market, i.e., when each match resulting from preference manipulations can be replicated or improved upon by some truncation / dropping strategies. We prove that for each stable mechanism, truncation strategies are exhaustive for each agent with quota 1 (Theorem 1). We show that this result cannot be extended neither to group manipulations (even when all quotas equal 1 – Example 1), nor to individual manipulations when the agent’s quota is larger than 1 (even when all other agents’ quotas equal 1 – Example 2). Finally, we prove that for each stable mechanism, dropping strategies are exhaustive for each group of agents on the same side of the market (Theorem 2), i.e., independently of the quotas.

Effect of auditory processing on the preference of monaural amplification for adults with symmetrical hearing loss

The purpose of this project was to determine if subjects with symmetrical hearing loss who prefer a monaural hearing aid fit to a binaural hearing aid fit may demonstrate an auditory processing disorder causing them to experience binaural interference when fit binaurally.

Subjective preference for a high power hearing aid utilizing a directional microphone

This paper discusses the use of a directional microphone by hearing aid users.

Cross-modal preference acquisition: evaluative conditioning of pictures by affective olfactory and auditory cues

In this research, a cross-model paradigm was chosen to test the hypothesis that affective olfactory and auditory cues paired with neutral visual stimuli bearing no resemblance or logical connection to the affective cues can evoke preference shifts in those stimuli. Neutral visual stimuli of abstract paintings were presented simultaneously with liked and disliked odours and sounds, with neutral-neutral pairings serving as controls. The results confirm previous findings that the affective evaluation of previously neutral visual stimuli shifts in the direction of contingently presented affective auditory stimuli. In addition, this research shows the presence of conditioning with affective odours having no logical connection with the pictures.

Pesticides, preference heterogeneity and environmental taxes

In this paper we present results from two choice experiments (CE), designed to take account of the different negative externalities associated with pesticide use in agricultural production. For cereal production, the most probable impact of pesticide use is a reduction in environmental quality. For fruit and vegetable production, the negative externality is on consumer health. Using latent class models we find evidence of the presence of preference heterogeneity in addition to reasonably high willingness to pay (WTP) estimates for a reduction in the use of pesticides for both environmental quality and consumer health. To place our WTP estimates in a policy context we convert them into an equivalent pesticide tax by type of externality. Our tax estimates suggest that pesticide taxes based on the primary externality resulting from a particular mode of agricultural production are a credible policy option that warrants further consideration.

The biocontrol fungus Pochonia chlamydosporia shows nematode host preference at the infraspecific level

A RAPD-PCR assay was developed and used to test For competitive variability in growth of the nematode biological control fungus Pochonia chlamydosporia. Saprophytic competence in soil with or without tomato plants was examined in three isolates of the fungus: RES 280 (J), originally isolated from potato cyst nematode (PCN) cysts; RES 200 (1) and RES 279 (S), both originally isolated from root knot nematode (RKN) eggs. Viable counts taken at 70 d indicated that I was the best saprophyte followed by S, with J the poorest. RAPD-PCR analysis of colonies from mixed treatments revealed that there was a cumulative effect of adding isolates to the system. This Suggested that the isolates did not interact and that they may occupy separate niches in soil and the rhizosphere. To investigate parasitic ability, soils were seeded with two isolates of the fungus: J and S, singly or in combination. Tomato or potato plants were grown in these soils; free of nematodes, or inoculated with PCN or RKN, and incubated for 77 d. The abundance of the PCN isolate J in PCN cysts was significantly greater than that of the RKN isolate S but in RKN egg masses, S was significantly more abundant than J. RAPD-PCR analysis of colonies from mixed treatments confirmed that J was more abundant than S ill PCN cysts whereas the converse was observed on RKN egg masses. This substantiates the phenomenon of nematode host preference at the infraspecific level of P. chlamydosporia and highlights its relevance for biological control of plant parasitic nematodes.