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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
31

Real consequences matter: Why hypothetical biases in the valuation of time persist even in controlled lab experiments

Krcal, Ondrej, Peer, Stefanie, Stanek, Rostislav, Karlinova, Bara 12 1900 (has links) (PDF)
In a controlled lab experiment, we investigate hypothetical biases in the value of time by comparing stated preference (SP) and revealed preference (RP) values attached to unexpected waiting times. The SP and RP choice sets are identical in terms of design with the only difference being that the RP choices have real consequences in terms of unexpected waiting times and monetary incentives. We find a substantial hypothetical bias with the average SP value of time being only 71% of the corresponding RP value. The bias is mainly driven by participants who have scheduling constraints during the time of the unexpected wait. Scheduling constraints are taken into account to a much lesser extent in the SP setting than in the RP setting, presumably because only in the latter, the consequences of ignoring them are costly. We find evidence that this effect is stronger for persons with relatively low cognitive ability.
32

Food preferences in captive meerkats (Suricata suricatta)

Salomonsson, Cecilia January 2011 (has links)
By using a three-choice preference test I tested food preferences in eight meerkats (Sutricata suricatta) for nine different food items. The meerkats were presented with all possible combinations of 9 food items, in total 84 combinations. The meerkats displayed the following rank order of food preference: cricket > zophoba lava > egg white > banana = tomato > orange > apple > cucumber > carrot. A correlation test between the food preference and nutritional content showed that the preference is significantly correlated with protein content. There is also a significant correlation between ash content and the food preference. There were no correlations with water, fat or vitamins and minerals. This suggests that, as in the wild, the captive meerkats at Kolmården wild life park seek food with high protein content. Ash has a high significant correlation with protein, which may explain the correlation between ash and the food preference. A comparison between the individual’s food preferences showed that the oldest individuals had the highest number of correlations with their food preferences to other individual’s food preference. This suggests an observational learning capability from older to younger individuals, which has also been reported in wild meerkat
33

Sexually Differentiated Object Preference in Rhesus Monkeys (Macaca mulatta)

Berkowitz, Jamie 01 January 2009 (has links) (PDF)
Children have strong preferences for sex-typed toys; boys prefer trucks, whereas girls prefer dolls. These preferences appear to be driven by complex interactions of hormones and the socio-cultural environment. The relative contribution of each of these factors in children is impossible to isolate given ethical limitations. Non-human primate species afford the opportunity to examine preferences in the absence of societal values and influences that children experience. In two previous studies with non-human primates, one with vervet monkeys and one with rhesus monkeys, monkeys showed sex-typed object preferences that paralleled those of children. However, several uncontrolled variables could have influenced these preferences. Our study considered object characteristics and we controlled for possible color preferences. We also tested monkeys individually to eliminate the effects of social facilitation and dominance rank. In experiment 1, monkeys were given a choice between similar objects of different colors (Phase A) and moving vs. non-moving objects (Phase B). In experiment 2, monkeys were given a choice between dolls and trucks (Phase A) and subsequent phases looked at the influence of moving wheels (Phase B) and hardness (Phase C). Contrary to previous findings, monkeys did not show sex-typed object preferences. Instead, the monkeys preferred blue objects, hard PVC objects such as trucks and hard dolls, and dolls with wheels. The influence of previous reward based cognitive testing, familiarity of substrate materials, and rearing condition are considered as possible explanations for these findings.
34

Stated and Revealed Preference Valuation of Forest Ecosystems

Li, Xiaoshu 27 August 2014 (has links)
Stated preference and revealed preference are two commonly conducted non-market value evaluation methods which can also be applied to make evaluation of forest ecosystem. In the application of these evaluation methodologies, there always exists limitation from the data collection and empirical analysis. In the dissertation here, I extend the traditional evaluation methods with novel design or statistical analysis approaches to solve the practical problem we met in evaluation of forest ecosystem. The first and second chapters are based on stated preference methods. The first chapter employ both the mail survey and on-site survey to investigate the preference for attributes of low-impact timber harvesting programs. In the second chapter, we recruit three interest groups for on-site survey and compare their preference for the low-impact timber harvesting programs. In these first two chapters, choice modeling method is employed to elicit the respondents' preferences, and I also use bootstrap method to get robust estimation results for small sample size data. The last chapter employed revealed preference method to evaluate the economic losses from hemlock damages caused by forest pest. Three different interpolation methods are employed to scale-up the analysis from sites to states. Based on the findings of all three chapters, we can see that these survey design and statistical methods help to overcome the limitations in empirical analysis of forest ecosystem and make more robust inferences for design forest protection policies. / Ph. D.
35

Vinflaskans färg, form och vikt : En studie av marknadsföring, konsumentpåverkan och preferens

Collin, Daniel, Nilsson, Patrik January 2013 (has links)
Vinmarknaden av idag präglas av allt tuffare konkurrens, och går från att ha varit traditionsbunden mot att bli mer och mer marknadsorienterad. Det går att se trender i att flaska och förslutning vid sidan av etikett börjat användas allt mer som marknadsföringsredskap. Denna studie avser belysa betydelsen av själva flaskan, genom att specialstudera tre flaskattribut: flaskans färg, form och vikt. Vinflaskans attribut undersöks avseende hur de används, eller kan användas, i marknadsföringssyfte för att påverka kundens preferens vid val av vin. Marknadsföringsaspekten begränsas till att behandla främst produktdifferentiering. Metoden för denna studie är i form av en litteraturstudie av fyra vetenskapliga artiklar. Resultatet uppvisar viss betydelse av flaskform, flaskfärg och flaskvikt för konsumenters preferens, men att dessa tenderar att vara underordnade andra attribut. Differentierande formgivning kan påvisas påverka konsumenter positivt, oavsett attribut. I diskussionen finner denna studie tydliga samband mellan hur produktdifferentiering som marknadsföringsstrategi beskrivs i litteraturen och hur vinkonsumenters preferensbeteende beskrivs i empirin, vilket leder till slutsatsen att strategierna har kundpåverkan. Studien finner även att det framför allt gällande flaskfärg och flaskvikt finns potential att utveckla den differentierande marknadsföringen ytterligare / B-uppsatser
36

The Relation Between Preference and Demand in the Domestic Hen: Does Preference Vary With Price?

Bruce, Julie-Anne Marie January 2007 (has links)
ABSTRACT Six hens responded under an increasing Fixed Ratio schedule of reinforcement to assess demand separately for two different food types: wheat and puffed wheat. Demand curves generated showed the least preferred food, puffed wheat, yielded a higher initial (ln L) demand than the more preferred food, wheat. While responding for the more preferred food, wheat, produced lower initial (ln L) demand functions, responding for wheat was maintained to higher increasing FR schedules of reinforcement than was that for puffed wheat. This phenomenon occurred across all six hens. To assess preference between the two food types the hens responded under a two-link concurrent-chain schedule of reinforcement. Under the concurrent-chain schedule of reinforcement there were three conditions, each consisted of a initial link with VI 90-s VI 90-s in effect, and terminal links of FR1, FR8 and FR32. The concurrent-chain schedule was used to examine if or how preference may relate to demand. Preference measures obtained showed wheat was generally preferred to puffed wheat across all prices throughout the preference assessment. As price increased in the terminal link during the preference assessment, preference for wheat became more extreme as did the hens responding. The results suggest that while there is a systematic relation between preference and demand, in that at higher FR values food with higher demand levels is preferred. This does not seem to hold, however, at FR1
37

Son preference and fertility in China, South Korea, and the United States

Min, Ho Sik 15 May 2009 (has links)
The goal of this dissertation is to contribute in three ways to the literature on son preference and fertility through a comparative perspective. First, I examine the impact of son preference on fertility in China and South Korea compared with the United States. The impact that a female birth has on the likelihood of a woman having another birth is of the most concern: Women who have one or two daughter(s) as previous child(ren) are expected to be more likely to experience the hazard of having a second or a third birth. Second, my dissertation attempts to examine the effects of women’s status on son preference if women’s education reduces son preference. Third, my dissertation examines son preference and fertility in the U.S. Even though the U.S. has never shown son preference regarding sex ratios at birth, recent research has shown this association to exist among poor Hispanics. My dissertation used data from a national sample, 2002 National Survey of Family Growth. The results showed that women in China and South Korea who had a daughter instead of a son as their first child had a higher hazard of having a second birth as expected. Moreover, the results showed that the hazard ratio of having a third birth for Chinese and South Korean women was almost four and five times more, respectively. As expected, the hazard ratios for the U.S. were not significant and thus did not support the hypothesis. And the more educated women who had a daughter(s) instead of a son(s) as their previous child(ren) were less likely to have a second birth, but not in the third birth. This means women’s education apparently does not reduce son preference in the case of the third birth. Thus, women’s education apparently has limited or no influence on the childbearing decision where son preference is strong. Third, Hispanic women with low socioeconomic status did not have a significant hazard ratio of having a higher order birth. Accordingly, the dissertation does not find any statistical evidence of American son preference at the national level.
38

Genetic Determinants of Cilantro Preference

Mauer, Lilli 14 December 2011 (has links)
Cilantro, the leaf of the Coriandrum sativum plant, has been documented as being one of the most polarizing and divisive foods known. It has been proposed that extreme disliking of this herb may be explained by genetic variation. The objectives of this thesis were to quantify the prevalence of cilantro disliking in various ethnocultural groups, to identify genetic polymorphisms that are associated with this trait using genome-wide association studies, and to analyze the associations of these polymorphisms within different ethnocultural groups. Prevalence of cilantro disliking was found to range from 3%, among Middle Eastern subjects, to 21% among East Asians. Two polymorphisms, one in the OR4N5 olfactory receptor gene and the other in the TAS2R1 taste receptor gene, were found to be associated with cilantro preference in the Caucasian subset of the study population. No statistically significant associations were observed within other ethnic groups.
39

Genetic Determinants of Cilantro Preference

Mauer, Lilli 14 December 2011 (has links)
Cilantro, the leaf of the Coriandrum sativum plant, has been documented as being one of the most polarizing and divisive foods known. It has been proposed that extreme disliking of this herb may be explained by genetic variation. The objectives of this thesis were to quantify the prevalence of cilantro disliking in various ethnocultural groups, to identify genetic polymorphisms that are associated with this trait using genome-wide association studies, and to analyze the associations of these polymorphisms within different ethnocultural groups. Prevalence of cilantro disliking was found to range from 3%, among Middle Eastern subjects, to 21% among East Asians. Two polymorphisms, one in the OR4N5 olfactory receptor gene and the other in the TAS2R1 taste receptor gene, were found to be associated with cilantro preference in the Caucasian subset of the study population. No statistically significant associations were observed within other ethnic groups.
40

Functional analysis of concealment: a novel application of prospect and refuge theory

Singh, Punya January 2009 (has links)
According to prospect-refuge theory, humans prefer to be in spaces that afford protection from threat (refuge), but also provide large fields of view (prospect). These preferences are said to arise from the adaptive advantages of such locations with respect to both avoidance of predation from refuge and survey of opportunities for resource collection by prospect. Prospect-refuge theory in the past has traditionally only been applied to human beings, but many of the same contingencies governing spatial preference ought to also hold true in other animals. If people's spatial preferences are influenced by prospect-refuge considerations, then such preferences ought to be found in other animals that are subject to the same pressures to find safety and resources. The overall objective of this study was to explore spatial preferences of the Mongolian gerbil in situations in which prospect-refuge theory makes specific predictions about which regions of an environment will be preferred. Gerbils were placed in an arena containing three dome shaped refuges that varied in the amount of prospect and refuge. A predator was released during the trial to examine how contextual factors may influence the degree of prospect and refuge preferred. There was a preference for an enclosed refuge at stimulus onset even though this was not reflective of what happened prior to stimulus onset, which suggests there was a shift in preferring refuges with greater concealment upon exposure to a threatening stimulus. These results indicate that shelter preference does in fact depend on contextual factors. An explicit comparison of these preferences in widely divergent species may help to place theories of spatial preference on a firmer biological footing, and may provide a greater understanding of how the principles of spatial cognition might underpin parts of the design process.

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