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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.
1

An investigation of the measurement of individual risk attitudes

Winter, John R. 06 December 1985 (has links)
Two direct elicitation of utility (D.E.U.) techniques were used to estimate risk attitudes of a group of agricultural producers. The two elicitation techniques used in the study were 1) an error-in-response model using a modified Ramsey method, and 2) stochastic dominance with respect to a function (SDF). The primary objective of the study was to determine whether the two elicitation techniques yield consistent estimates of risk attitudes. A second major objective of the study was to provide additional information about the distribution of risk attitudes among agricultural producers. The study confirmed the results of other research efforts that the majority of risk attitude parameters of agricultural producers lie within the range -.0001 and .001 with income measured in dollars [King and Robison, 1980]. The study also supports previous research results which indicate that a significant portion of decision makers exhibit risk preferring behavior, at least over some ranges of incomes. The error-in-response model classified 38.1% of the respondents as risk preferring, 47.6% as risk neutral, and 14.3% as risk averse. With only one exception, the SDF technique elicited risk preferring attitudes for every respondent over some range of income values. Individual and aggregate tests for decreasing (increasing) absolute risk aversion were conducted. No respondents were found to exhibit increasing or decreasing absolute risk aversion. The statistical comparison of the two elicitation techniques was inconclusive. A paired t-test failed to reject the null hypothesis of no difference in the estimated risk attitudes. However, the correlation between the two measures was virtually zero (-.046) suggesting that the two measures of risk attitudes are not closely related. The two elicitation techniques were also compared on other grounds. Both elicitation techniques are designed to prevent certainty bias that has plagued other D.E.U. methods. The SDF technique is found to be superior in overcoming possible interviewer bias. Neither technique is superior in coping with probability bias. The SDF technique is easier to implement but the error-in- response questionnaire is easier to formulate. The error-in- response model results in a specific estimate of the respondent's risk attitude when the negative exponential utility function is used. Based on the comparisons made in the study, the SDF procedure is considered to be superior to the error-in-response model for eliciting risk attitudes. / Graduation date: 1986
2

Farmers' risk attitudes in the eastern high plateau region of Algeria : an application of the experimental approach

Belaid, Abderrezak 18 October 1985 (has links)
Farmers in the high plateau region of Algeria are assumed to exhibit risk averse behavior, particularly, due to highly variable weather conditions inducing income instability over time. This in turn directly affects their production behavior. The Eastern High Plateau (Setif) is not a homogeneous region. In the El-Eulma daira, for example, three different agroecological zones have been identified on the basis of climate, topography and soil quality. In addition, two distinct agricultural sectors (private and socialist) coexist side by side in each of the agroecological zones. This study constitutes an attempt to measure farmers' risk attitudes in three communes (El-Eulma, Oum Ladjoul and Beni Fouda) which are representative of the three agroecological zones of the El-Eulma daira. Farmers' risk attitudes were measured through the experimental approach developed by Binswanger in India. The technique used consisted of presenting the subjects, i.e. the farmers, with a set of alternative prospects involving real money. Based on the derived risk aversion coefficients, a series of tests was run to determine if farmers' risk attitudes are dependent on the zone and/or the sector. The effect of socioeconomic characteristics (age, schooling, number of working children, etc.) on partial risk aversion was analyzed. Finally, the derived risk aversion coefficients were used in a risk programming model (MOTAD) to determine optimal farming plans for private as well as socialist sector farmers. The experiment results indicate that regardless of the zone and the sector, farmers unanimously exhibit risk averse attitudes. At low payoff level, the distribution of risk preferences is more spread. A narrower distribution occurs at higher payoff levels (e.g. 200 DA scale). There was no evidence of significant difference among sites and between sectors. Also socioeconomic attributes correlate poorly with the estimated partial risk aversion coefficients. In the socialist sector major discrepancies between the risk programming model solutions and actual activity levels occured. They were expected because of the specific structure of this sector. The inclusion of government cropping pattern recommendations in the constraint matrix indicates that government interventions have a different effect on socialist farmers' welfare of the three zones. / Graduation date: 1986
3

Contribution of risk-taking behaviors to falls for Chinese elderly

Cheung, Hiu-yee, Alice., 張曉怡. January 2006 (has links)
published_or_final_version / Medical Sciences / Master / Master of Medical Sciences
4

The effect of blood alcohol concentration on performance in a game of risk involving industrial tasks and accidents

Motosko, Michele Marie January 1987 (has links)
The reported study measured the effects of alcohol on risk-taking 511 a penalty/incentive system. Subjects read scenarios involving industrial tasks and accidents from a video screen. Each scenario had a point value associated with it. Subjects had to decide whether they were willing to perform the task if there was a specified probability of having an accident. They would win points for successfully performing the task, but lose points for having an accident. Their goal was to score as many points as possible. The points won were used to buy tickets for one of two $100.00 drawings. Those with the most tickets had the highest probability of winning the drawing. This motivator was used to stimulate cautious decision-making about taking risks. Prior to participation in the task, subjects ingested a mixture of orange juice and 80-proof vodka to yield one of four BAC levels (0.00%, 0.05%, 0.07%, or 0.09%); however, alcohol was not found to affect risk-taking in this study. The concept of risk compensation is used to assist in the interpretation of the results. Prior to discussion of the methodology and results of the current study, the literature on the Theory of Risk Homeostasis and on the effect of alcohol on industrial tasks is given to show how this study fits into the spectrum of research. Lastly, recommendations are given for various considerations in conducting research on risk-taking and alcohol. / Master of Science / incomplete_metadata
5

The Creation and Validation of the Activation-Valence Affective Traits Survey (AVATS)

Coskunpinar, Ayca 03 July 2012 (has links)
Indiana University-Purdue University Indianapolis (IUPUI) / Aim: The goals of the current studies were to (a) create a measure of affective traits that can assess both the discrete and the underlying dimensions of affective traits and (b) examine the reliability and validity of the scale in two independent samples. Participants: Participants were undergraduate students at a large, public US mid-western university (Study 1 N = 616; Study 2 N = 510). The mean age for Study 1 was 21.10 (SD = 5.05) and 21.02 for Study 2 (SD = 4.96). Design: Exploratory and confirmatory factor analyses were conducted to examine internal factor structure of the scale. A series of correlational, reliability, and hierarchical regression analyses were conducted to examine convergent, divergent, and criterion-related validity of the new scale. Findings: Activation-Valence Affective Traits Survey (AVATS) had good reliability and adequate construct, convergent, and discriminant validity as a measure of affective traits. Conclusions: This study introduces a new scale for measuring affective traits that offers more information on both the categorical and dimensional conceptualizations of affective traits, which also has predictive utility in relation to problem-related alcohol consumption.
6

Drinking Rhythms in Alcohol Preferring Mice

Matson, Liana M. 29 August 2012 (has links)
Indiana University-Purdue University Indianapolis (IUPUI) / Multiple lines of High Alcohol Preferring (HAP) mice were selectively bred for their intake of 10% ethanol (v/v) during 24-h daily access over a four-week period, with the highest drinking lines exhibiting intakes in excess of 20 g/kg/day. Drinking rhythms and corresponding blood ethanol concentrations (BEC) of the highest drinking HAP lines to those of the C57BL/6J (B6) inbred strain. Adult male and female crossed HAP (cHAP), HAP1 and B6 mice had free-choice access to 10% ethanol and water for 3 weeks prior to bi-hourly assessments of intake throughout the dark portion of a reverse 12:12 light dark cycle. In another cohort of cHAP mice, the same procedure was used to assess bi-hourly ethanol intake, and blood samples were taken across the day to look at the pattern of accumulation in these mice. Finally, considering the high level of intake by cHAP mice, we were interested in assessing whether metabolic and functional tolerance develop following chronic free-choice access, which were assessed using 2.0 and 1.75 g/kg challenge doses of 20% ethanol, respectively. cHAP and HAP1 mice maintained an excessive level of intake throughout the dark portion of the cycle, accumulating mean BEC levels of 261.5 + 18.09 and 217.9 + 25.02 mg/dl at 7-8 hours following lights off, respectively. B6 mice drank comparatively modestly, and did not accumulate high BEC levels (53.63 + 8.15 mg/dl). In the cHAP cohort, mean BECs were 112.47 + 19.91 at 2 hours after lights off, 189.00 + 27.40 at 6 hours after lights off, 193.80 + 29.66 at 10 hours after lights off, and 89.68 + 22.19 at 2 hours after lights on. Further, following 3 weeks of ethanol access, cHAP mice had a faster rate of ethanol metabolism and fewer hind slips than water-only exposed mice (ps < .05). In conclusion, the excessive free-choice drinking demonstrated by the HAP1 and cHAP lines, as well as the pattern of sustained high BECs in cHAP mice, challenge the notion that rodents will not reliably and voluntarily sustain ethanol intake at pharmacologically relevant levels. These results suggest that the highest drinking HAP lines may provide a unique opportunity for modeling the excessive intake that has been observed in alcohol-dependent individuals. Further, we observed that cHAP mice develop both metabolic and functional tolerance to the ataxic effects of ethanol following 3 weeks of free-choice access. Together, these findings support HAP mice as translational rodent model of alcoholism, and provide rationale for exploration of the predisposing factors for excessive consumption, as well as the development of physiological, behavioral, and toxicological outcomes following alcohol exposure.
7

Characterization of Behavioral Profiles for Inbred P and NP and Congenic P.NP and NP.P Rats

Jensen, Meredith 27 August 2012 (has links)
Indiana University-Purdue University Indianapolis (IUPUI) / Alcoholism inheritance rates have been estimated as high as 60% in a human population. Many significant features of alcohol dependence have been replicated in rodent animal models of alcoholism, however not in totality. These animal models include inbred preferring (iP) and nonpreferring (iNP) rat types. Congenic rats have been engineered from the iP and iNP strains whereby a P congenic rat has in its genome a well-chosen chromosomal portion taken from an NP rat (P.NP) and, reciprocally, an NP congenic rat has acquired the analogous DNA from a P rat (NP.P). In this case, a quantitative trait locus (QTL) from chromosome 4 is the donor genetic material for the congenic rats. It is of great interest to further study this chromosome 4 QTL because it has been found to control a significant portion of ethanol consumption behavior in iP and iNP rats. This study aimed to behaviorally profile the iP, iNP and reciprocal congenic rats. As a result of the behavioral profiling of these genetically related groups, some conclusions could be made regarding which behaviors appear to be controlled by the chromosome 4 donor DNA.This study primarily utilized the Multivariate Concentric Square Field apparatus (MCSF) to characterize behavioral profiles for the inbred and congenic rats. The Open field (OF) and Elevated plus maze (EPM) supported this effort. The MCSF is valuable in that it allows for the animals to interact within an environment that has ethological value. The 12 different zones that make up the field are characterized by some functional quality in terms of type and duration of behavior performed, etc. The behavioral data is aggregated and finally represented in terms of five functional categories, the elements of the behavioral profile: general activity, exploratory activity, risk assessment, risk taking, and shelter seeking. The study hypotheses were shaped by prior research suggesting that iPs should display lower general activity and risk taking strategy than iNPs in the MCSF. Inbred Ps should be more active in the OF and spend more time in the center of the EPM. Generally, it is expected that the iP QTL confer behavioral phenotypes to the iNP strain that deviate toward a "P" behavioral phenotype and reciprocally, the iNP QTL confer behavioral phenotypes to the iP strain that deviate toward an "NP" behavioral phenotype. The results showed that iP rats performed more risk assessment and risk taking behavior and less shelter seeking and anxiety-like behavior than iNP rats. It followed that P.NP congenic rats significantly downgraded their risk assessment and risk taking behavior when compared to iP rats. This decrease can be attributed to the chromosome 4 QTL donated from the iNP breed. All together this study concludes that risk assessment and risk taking behavior in the iP rats is controlled by the same DNA region that, in part, determines voluntary intake of ethanol consumption. Further fine mapping of the QTL region should help in discovering if the same DNA sequences that influence ethanol intake also significantly influence risk behavior.

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