Stereographic virtual environments display data in such a way that a user perceives objects within the displayed environment to be separated in depth from the display itself. The effectiveness of stereographic virtual environments as learning tools has been evaluated relative to factors such as multidimensional cues, user interaction, and learner characteristics. This study has examined the relationship between two evaluative factors: the presence of stereographic depth cues and field dependence, a learner characteristic associated with performance on visual tasks. Adult learners were identified on a field dependence continuum based on scores on the Group Embedded Figures Test. Each student received instruction related to the heart using stereographic materials or nonstereographic materials, depending on assignment to treatment group. All participants were given two tests, identification and terminology, following this instruction. The scores on the combination of these tests, denoted as the Modified Total Criterion Test (MTCT), represented the level of visual recall relative to the instructional materials reviewed. Analyses of variance revealed an interaction effect between the level of field dependence and the presence of stereographic depth cues within a virtual environment such that field independent participants scored higher on tests of visual recall within stereographic conditions versus nonstereographic conditions and field dependent participants scored lower within stereographic conditions versus nonstereographic conditions. / Ph. D.

Made available in DSpace on 2016-07-27T14:20:37Z (GMT). No. of bitstreams: 1 Mychelle Borges Pereira Pinto.pdf: 494967 bytes, checksum: 9e839594858e583a9be5242d71ac14fb (MD5) Previous issue date: 2005-12-20 / The relations between verbal and non-verbal operant classes have been studied by a field called say-do; do-say correspondence . The present study had the following aims: (1) to verify if successive manipulations of reinforcers and punishments contingent on dependent and independent operants (say/do classes), influence each other; (2) to verify if the effects of the application of reinforcers and punishment on independent operant classes (say/do classes) and (3) to verify if reinforcing and punishing dependent operant classes (say/do classes), correspondence between these operant classes occurs. To realize this study three experiments were done. In experiment I eight university students participated. All of them were exposed to five experimental phases. The results of experiment I showed that contingencies of reinforcement were effective to promoting correspondence between independent operant classes for six of the eight participants. The two other participants did not show correspondence in all phases. In experiment II nine university students participated, being exposed to three experimental phases. The results showed that the contingencies of reinforcement and punishment during phase 2 were effective in promoting correspondence between dependent operant classes. In this experiment two variables were manipulated at the same time. To solve this problem experiment III was outlined. In experiment III, eight university students participated, being exposes to three experimental phases. The results showed that the contingencies of reinforcement and punishment during phase 2 were effective in promoting correspondence between independent operant classes. Experiment III was outlined to identify what variable controlled the behavior of the participants. The results showed that the controlling variable was the relation of functional dependence. Together, these experiments made it possible to verify that correspondence is a phenomenon that can be established through contingency procedures, or, when dependency contingencies between operant classes are organized, the probability of correspondence between saying and doing to occur. / As relações entre classes de operantes verbais e não-verbais foram estudadas em uma área denominada de correspondência: dizer-fazer; fazer-dizer. O presente estudo teve como objetivos: (1) verificar se manipulações sucessivas de reforçadores e punições contingentes a classes de operantes dependentes e independentes (classes de dizer/fazer), influenciam uma às outras; (2) verificar os efeitos da apresentação dos reforçadores e da punição de classes de operantes independentes (classes de dizer/fazer) e (3) averiguar se reforçando e punindo classes de operantes dependentes (classes de dizer/fazer), ocorre correspondência entre essas classes de operantes. Para realizar este estudo foram desenvolvidos três experimentos. No Experimento I participaram oito estudantes universitárias. Todas foram expostas a cinco Fases Experimentais. Os resultados do Experimento I demonstraram que contingências de reforçamento foram efetivas para promover correspondência entre classes de operantes independentes para seis das oito participantes. As duas outras participantes não fizeram correspondência em todas as Fases. O Experimento II contou com a participação de nove estudantes universitárias, expostas a três Fases Experimentais. Os resultados mostraram que as contingências de reforçamento e punição durante a Fase 2 foram efetivas para promover correspondência entre classes de operantes dependentes. Neste experimento foram manipuladas duas variáveis ao mesmo tempo. Para resolver este problema foi delineado o Experimento III. No Experimento III, participaram oito estudantes universitários expostos a três Fases Experimentais. Os resultados demonstraram que as contingências de reforçamento e punição durante a Fase 2 foram efetivas para promover correspondência entre classes de operantes dependentes. O Experimento III foi delineado com o objetivo de identificar qual variável estava controlando o comportamento das participantes. Os resultados demonstraram que a variável controladora foi a relação de dependência funcional. O conjunto de experimentos possibilitou verificar que a correspondência é um fenômeno a ser estabelecida via procedimento de contingenciamento, ou seja, quando se organiza as contingências de dependência entre classes operantes, aumenta-se a possibilidade de ocorrer correspondência entre Fazer e Dizer.

by Leung Hiu-shan. / Thesis submitted in: June 1999. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2000. / Includes bibliographical references (leaves 55-58). / Abstracts in English and Chinese. / ABSTRACT --- p.ii / ACKNOWLEDGEMENTS --- p.iv / TABLE OF CONTENTS --- p.v / LIST OF TABLES --- p.vi / LIST OF FIGURES --- p.vii / LIST OF APPENDICES --- p.viii / INTRODUCTION --- p.1 / Weak Central Coherence of Autism --- p.1 / Cognitive Style of Field Dependence/Independence --- p.4 / Visual Illusions --- p.5 / Summary of Previous research & Objectives and Hypotheses of Present Study --- p.8 / METHOD --- p.12 / Participants --- p.12 / Stimuli --- p.13 / Procedure --- p.19 / RESULTS --- p.24 / EFT --- p.24 / RFT --- p.26 / Correlation between EFT and RFT --- p.26 / Visual illusions --- p.30 / "Relationship between EFT, RFT and Visual Illusions" --- p.34 / Percentage of Subjects Succumbed/Not succumbed to Geometric Illusions --- p.44 / DISCUSSION --- p.44 / REFERENCES --- p.55 / APPENDICES --- p.59

This study describes the subjective psychological experience of African women positively living with and dying of HIV/AIDS, with a focus on the significant cognitive, emotional and social themes involved in their subjective sense of coping. HIV-positive African women have been identified as being at risk psychologically, due to gender inequality in African culture and society and the stigma that surrounds HIV/AIDS. Their traditional role as caregivers also places them at risk, but highlights the importance of understanding their experience in order to assist these women and their children. Drawing on interpretive methods within a qualitative research approach, ten women who are coping with their HIV-positive status were interviewed in order to gain an understanding of their experiences of coping with HIV/AIDS. The analysis of the interview material suggests that coping is a process of disconnection and reconnection that entails the ability to know one’s own experience. Coping was found to be a process of mourning in which the individual moves from a time of not coping toward acceptance of their status and the changes this necessitates in their relationships. Resolution of mourning seemed to entail greater integration of these women’s sense of themselves and psychological strength was found to originate in coping with adversity. The study draws on three theoretical approaches, namely positive psychology, object relations theory and analytical psychology. Carl Jung’s theory of individuation and Joseph Campbell’s interpretation of it, The Hero’s Journey, was used as a frame for the theoretical discussion. Within this frame, Elizabeth Kubler-Ross’ stages of mourning were integrated with Donald Winnicott’s description of separation in the move from dependence to independence, Winnicott’s ideas around the capacity to be alone, Melanie Klein’s description of the move from the paranoid-schizoid to the depressive position and Wilfred Bion’s ideas around the desire to know one’s own experience. Throughout the discussion a number of concepts from positive psychology were explored, such as: coping styles, social support, participation in life, positive goals, autonomy and resilience. The core of Jung’s theory, which is the integration of all aspects of the self, allowed space to explore distress and coping, both of which are entailed in the process of coping. / Thesis (PhD)--University of Pretoria, 2010. / Psychology / unrestricted

This study was designed to examine whether a person's prepositioned cognitive style influenced learning achievement in a visually-oriented task for an online learning environment in higher education. Field dependence-independence was used to identify individuals' cognitive styles. A true experimental study was conducted in the fall 2005 term at the University of Central Florida. This researcher followed Dwyer and Moore's research (1991, 2002) and divided learners into three groups (field dependent [FD], field neutral [FN], and the field independent [FI] students). Eighty-three preservice teachers participated in this study; the data from 52 of the FD and the FI participants were analyzed to answer research questions. The findings in this study supported those in the literature review; students from both FD and FI cognitive styles performed equally well in online learning environments. In addition, for providing introductory-level instruction on visually-oriented tasks in an online learning environment, instructions which emphasized an FD approach benefited both FI and FD students in their knowledge-based learning achievement. In this approach, extra cues and sequence of content might have been the reasons that students had higher scores on their knowledge-based learning achievement and satisfaction levels. The findings of this study also indicated that students could demonstrate higher performance-based learning achievement if they had more experiences on the subject matter and higher knowledge-based learning achievement if they felt the instructions were easy to follow and the workload of the module was manageable. Based on the findings and conclusions, the recommendations are: (1) A larger sample size is needed to generalize the findings of the study; (2) In this study, student-to-student and teacher-to-student interactions might affect students' learning achievement. Future studies should consider those interactions as factors and examine their effect on students' learning achievement.

No description available.

The purpose of the present study is to identify 10th grade students&rsquo / use of proof schemes in geometry questions and to investigate the differences in the use of proof schemes with respect to their cognitive style and gender. The sample of the study was 224 tenth grade students from four secondary schools. Of those, 126 participants were female and 98 participants were males. Data was collected at the end of the academic year 2005-2006 through uses of two data collection instruments: Geometry Proof Test (GPT) and Group Embedded Figure Test (GEFT). GPT, included eleven open-ended questions on triangle concept, was developed by researcher to investigate students&rsquo / use of proof schemes. The proof schemes reported by Harel and Sowder (1998) were used as a framework while categorizing the students&rsquo / responses. GEFT developed by Witkin, Oltman, Raskin and Karp (1971) was used to determine cognitive styles of the students as field dependent (FD), field independent (FI) and field mix (FM). To analyze data, descriptive analyses, repeated measure ANOVA with three proof schemes use scores as the dependent variables and a 2 (gender) x 3 (cognitive styles: FD, FM, FI) multivariate analysis of variance (MANOVA) with three proof schemes use scores as the dependent variables was employed. The results revealed that students used externally based proof schemes and empirical proof schemes significantly more than analytical proof schemes. Furthermore, females used empirical proof schemes significantly more than the males. Moreover, field dependent students used externally based proof schemes in GPT significantly more than field independent students. Also, field independent students use analytical proof schemes significantly more than field dependent mix students. There was no significant interaction between gender and cognitive style in the use of proof schemes. The significant differences in students&rsquo / use of proof schemes with respect to their gender and FDI cognitive style connote that gender and FDI cognitive styles are important individual differences and should be taken into consideration as instructional variables, while teaching and engaging in proof in geometry and in mathematics.

This study gives a platform to three old retired people who are constructed to be enjoying well-being and life satisfaction or going through life dissatisfaction after retirement. The epistemological framework was social constructionism. In-depth interviews with these three individuals were carried out. The premises of qualitative research were followed. The ‘case study approach’ was chosen as the most suitable method to gather information. Thematic content analysis was employed as a method of analysis of life stories of old retired people, which were reconstructed in terms of themes. Recurring themes in the life stories were then discussed and linked with the broader literature. The research allowed rich and informative information about life stories of three old retired people to emerge. Among the identified themes were financial status relating to adequate and appropriate sustenance after retirement; social networks and their effects on life satisfaction and dissatisfaction after retirement; health status; and cognitive functions in late adulthood. Everyone wishing to understand life in old age after retirement is encouraged to read this story. It is necessary to be sufficiently equipped in the event of an extended lifespan. / Psychology / M.A.(Psychology)

Les catastrophes naturelles comme les canicules, les tempêtes ou les précipitations extrêmes, proviennent de processus physiques et ont, par nature, une dimension spatiale ou spatiotemporelle. Le développement de modèles et de méthodes d'inférences pour ces processus est un domaine de recherche très actif. Cette thèse traite de l'inférence statistique pour les événements extrêmes dans le cadre spatial et spatio-temporel. En particulier, nous nous intéressons à deux classes de processus stochastique: les processus spatiaux max-mélange et les processus max-stable spatio-temporels. Nous illustrons les résultats obtenus sur des données de précipitations dans l'Est de l'Australie et dans une région de la Floride aux Etats-Unis. Dans la partie spatiale, nous proposons deux tests sur le paramètre de mélange a d'un processus spatial max-mélange: le test statistique Za et le rapport de vraisemblance par paire LRa. Nous comparons les performances de ces tests sur simulations. Nous utilisons la vraisemblance par paire pour l'estimation. Dans l'ensemble, les performances des deux tests sont satisfaisantes. Toutefois, les tests rencontrent des difficultés lorsque le paramètre a se situe à la frontière de l'espace des paramètres, i.e., a ∈ {0,1}, dues à la présence de paramètre de “nuisance” qui ne sont pas identifiés sous l'hypothèse nulle. Nous appliquons ces tests dans le cadre d'une analyse d'excès au delà d'un grand seuil pour des données de précipitations dans l'Est de l'Australie. Nous proposons aussi une nouvelle procédure d'estimation pour ajuster des processus spatiaux max-mélanges lorsqu'on ne connait pas la classe de dépendance extrêmal. La nouveauté de cette procédure est qu'elle permet de faire de l'inférence sans spécifier au préalable la famille de distributions, laissant ainsi parle les données et guider l'estimation. En particulier, la procédure d'estimation utilise un ajustement par la méthode des moindres carrés sur l'expression du Fλ-madogramme d'un modèle max-mélange qui contient les paramètres d'intérêt. Nous montrons la convergence de l'estimateur du paramètre de mélange a. Une indication sur la normalité asymptotique est donnée numériquement. Une étude sur simulation montrent que la méthode proposée améliore les coefficients empiriques pour la classe de modèles max-mélange. Nous implémentons notre procédure d'estimations sur des données de maximas mensuels de précipitations en Australie dans un but exploratoire et confirmatoire. Dans la partie spatio-temporelle, nous proposons une méthode d'estimation semi-paramétrique pour les processus max-stables spatio-temporels en nous basant sur une expression explicite du F-madogramme spatio-temporel. Cette partie permet de faire le pont entre la géostatistique et la théorie des valeurs extrêmes. En particulier, pour des observations sur grille régulière, nous estimons le F-madogramme spatio-temporel par sa version empirique et nous appliquons une procédure basée sur les moments pour obtenir les estimations des paramètres d'intérêt. Nous illustrons les performances de cette procédure par une étude sur simulations. Ensuite, nous appliquons cette méthode pour quantifier le comportement extrêmal de maximum de données radar de précipitations dans l'Etat de Floride. Cette méthode peut être une alternative ou une première étape pour la vraisemblance composite. En effet, les estimations semi-paramétriques pourrait être utilisées comme point de départ pour les algorithmes d'optimisation utilisés dans la méthode de vraisemblance par paire, afin de réduire le temps de calcul mais aussi d'améliorer l'efficacité de la méthode / Natural hazards such as heat waves, extreme wind speeds, and heavy rainfall, arise due to physical processes and are spatial or spatio-temporal in extent. The development of models and inference methods for these processes is a very active area of research. This thesis deals with the statistical inference of extreme and rare events in both spatial and spatio-temporal settings. Specifically, our contributions are dedicated to two classes of stochastic processes: spatial max-mixture processes and space-time max-stable processes. The proposed methodologies are illustrated by applications to rainfall data collected from the East of Australia and from a region in the State of Florida, USA. In the spatial part, we consider hypothesis testing for the mixture parameter a of a spatial maxmixture model using two classical statistics: the Z-test statistic Za and the pairwise likelihood ratio statistic LRa. We compare their performance through an extensive simulation study. The pairwise likelihood is employed for estimation purposes. Overall, the performance of the two statistics is satisfactory. Nevertheless, hypothesis testing presents some difficulties when a lies on the boundary of the parameter space, i.e., a ∈ {0,1}, due to the presence of additional nuisance parameters which are not identified under the null hypotheses. We apply this testing framework in an analysis of exceedances over a large threshold of daily rainfall data from the East of Australia. We also propose a novel estimation procedure to fit spatial max-mixture processes with unknown extremal dependence class. The novelty of this procedure is to provide a way to make inference without specifying the distribution family prior to fitting the data. Hence, letting the data speak for themselves. In particular, the estimation procedure uses nonlinear least squares fit based on a closed form expression of the so-called Fλ-madogram of max-mixture models which contains the parameters of interest. We establish the consistency of the estimator of the mixing parameter a. An indication for asymptotic normality is given numerically. A simulation study shows that the proposed procedure improves empirical coefficients for the class of max-mixture models. In an analysis of monthly maxima of Australian daily rainfall data, we implement the proposed estimation procedure for diagnostic and confirmatory purposes. In the spatio-temporal part, based on a closed form expression of the spatio-temporal Fmadogram, we suggest a semi-parametric estimation methodology for space-time max-stable processes. This part provides a bridge between geostatistics and extreme value theory. In particular, for regular grid observations, the spatio-temporal F-madogram is estimated nonparametrically by its empirical version and a moment-based procedure is applied to obtain parameter estimates. The performance of the method is investigated through an extensive simulation study. Afterward, we apply this method to quantify the extremal behavior of radar daily rainfall maxima data from a region in the State of Florida. This approach could serve as an alternative or a prerequisite to pairwise likelihood estimation. Indeed, the semi-parametric estimates could be used as starting values for the optimization algorithm used to maximize the pairwise log-likelihood function in order to reduce the computational burden and also to improve the statistical efficiency

La contribution relative des différentes entrées sensorielles dans le contrôle postural a souvent été étudiée dans le cadre de la posture érigée fondamentale. L’objectif de nos travaux a été de déterminer cette contribution dans deux postures relativement proches dans leur configuration : l’appui tendu renversé (ATR) et la verticale inversée (VI) en milieu aquatique. Si la vision est souvent considérée comme information principale dans le contrôle postural de la station érigée, la configuration structurelle (champ visuel restreint en ATR, immersion de l’œil en VI) de ces deux postures laisse imaginer un fonctionnement différent. La perturbation des différents capteurs sensoriels impliqués dans le contrôle postural a permis d’observer la réorganisation mise en place par le système nerveux central (SNC) pour y remédier. De plus la prise en compte d’un facteur perceptif comme la dépendance au champ visuel nous a paru être un élément pertinent pour tenter d’observer d’éventuelles différences interindividuelles dans les comportements des sujets. La perturbation du contrôle postural a été évaluée au travers d’une analyse cinématique et d’une analyse stabilométrique de l’ATR (analyse classique et non-linéaire). Les résultats de ces analyses laissent entrevoir des différences de stratégie entre les sujets dépendants et indépendants au champ visuel dans le contrôle de l’appui tendu renversé, ce qui ne semble pas être le cas en verticale inversée / The relative contribution of the different sensory inputs in erect postural control has often been studied. The aim of this work is to determine this contribution in two positions relatively close in their configuration: the handstand and the upside-down posture in water. If vision is often considered as the main information in postural control, the structural configuration (restricted visual field in handstand, eye’s immersion in upside-down posture) of these two postures lets imagine a different operation. Disruption of sensory receptors involved in postural control has allowed observing the reorganization implemented by the central nervous system (CNS). In addition, the visual field dependence appeared to be a relevant factor to observe interindividual behavioral differences. Disturbance of postural control was assessed through a kinematic analysis and a stabilometric analysis of the handstand (classical analysis and non-linear analysis). Results of these analyzes suggest different strategy according to visual field dependence in the control of the handstand, which does not seem to be the case in upside-down posture