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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.
281

COMPETITION, STATUS AND MARKETS

Channagiri Ajit, Tejaswi 01 January 2018 (has links)
Extant research within competitive dynamics recognizes a positive relationship between high levels of competitive activity and firm performance, but the cognitive and psychological antecedents to competitive activity are far less clearly understood. I explore the role of a specific psychological antecedent - status, in impacting firms’ motivations to launch competitive moves against rivals. The key question, which extant literature does not seem fully equipped to answer, is when and under exactly what circumstances lower-status firms become motivated to launch action against higher-status ones and vice-versa. I use the stimulus-response model in social cognition to build theory which helps to answer the question by considering structural properties of market engagement. The specific structural property of market engagement that I focus on is market commonality, or the extent to which a rival is a significant player in markets important to a focal firm. I predict that a rival’s market commonality with a focal firm and its status relative to the focal firm have independent and positive effects on the extent to which the focal firm pays attention to the rival, that a rival’s market commonality with a focal firm and its status relative to the focal firm interact negatively to predict the focal firm’s motivation to launch action against that rival, and that a rival’s relative status and market commonality with a focal firm interact positively to predict the extent to which the focal firm pays attention to the rival. I test theory through a field study on gourmet food trucks in Lexington and an experiment through Amazon’s Mechanical Turk tool. Results provide broad support for the hypotheses. Three consequences follow from my study – that high-status firms are likely to come under attack from lower-status firms with whom they do not compete in markets, that they are unlikely to be paying attention to those lower-status firms when first attacked, and that they are likely to become aware of and motivated to act against those lower-status firms only after the lower-status firms have occupied key markets. My study contributes to the literatures in competitive dynamics, status, multi-market contact, and entrepreneurial action.
282

Reaching into response selection: stimulus and response similarity influence central operations

Wifall, Timothy Curtis 01 July 2014 (has links)
This dissertation examines the impact of stimulus and response similarity on response selection. Traditional models of response selection invoke a central processor that operates like a look-up table by matching the perceptually classified stimulus (e.g., green square) to the specified response (e.g., right button press). The look-up property of response selection affords the system the ability to map any stimulus onto any response, even if that stimulus-response has never been paired before. Under such an approach, the degree of perceptual similarity or dissimilarity that exists among stimuli in the environment should have little effect on central operations, the similarity or dissimilarity of the motor response executed in response to a stimulus should not influence response selection, and no interaction between stimulus and response features is permitted, given that stimulus features affect the encoding process, and response features affect the output process, but not response selection itself. Eight studies examine the influence of stimulus and response similarity during response selection. The first two experiments establish the interaction across different task demands between stimulus and response similarity. The interaction was not the result of perceptual difficulty (Experiment 3) and was extended to a new set of stimuli (Experiment 4). A consequence of the design in Experiments 1 - 4 was that response condition was confounded with response configuration. In one of the response conditions the target location had three competitors on one side of it compared to the other condition where the target had one competitor on one side and two others on the other side. Experiments 5 and 6 examined the separate roles that response configuration and response metrics had on the interaction between stimulus and response similarity. The mechanism that produced the interaction was the result of competition between partially activated stimulus-response alternatives. Experiments 7 and 8 further explored the role of competition during response selection by turning to traditional response selection methodologies that introduce competition through either the presentation of irrelevant stimulus information or through presenting the stimulus along an irrelevant spatial dimension. These data have broad implications for models of RS. To account for the ability to pair any stimulus modality with any response modality dominant accounts of RS assume that central operations are performed by a generic set of processes that operate over representations that are stripped of metric information (amodal representations). Response selection works as a look-up table that receives a categorized stimulus as an input and returns an abstract response code as output. This type of model cannot produce an interaction between stimulus and response similarity and thus, the present data provide a serious challenge to these types of models. Finally, the data provide evidence that the metric relationship between stimuli and response matter and influence response selection. The co-activation of stimulus-response alternatives are at a level of representation that includes both stimulus and response properties. A framework is presented that captures key aspects of the data.
283

An examination of the temporal and spatial stimulus control in emergent symmetry in pigeons

Frank, Andrea Jean 01 January 2007 (has links)
If an organism is explicitly taught an A->B association, then might it also spontaneously learn the symmetrical B->A association? There is only a small amount of evidence that attests to the detection of emergent symmetry in nonhuman animals (e.g., one chimpanzee and two pigeons). This report examines the necessary and sufficient conditions for finding emergent symmetry in pigeons while attempting to control for the problems of spatial and temporal location found in previous symmetry and stimulus equivalence experiments. Using a successive go/no go matching-to-sample procedure, which showed all of the training and testing stimuli in one location, four experimental manipulations were examined. In Experiment 1 temporal location was controlled without the inclusion of identity matching intermixed with arbitrary matching; Experiment 2 contained identity matching with stimuli different from arbitrary matching; in Experiment 3 identity matching was trained to criterion and then intermixed with arbitrary matching; and in Experiment 4 two sets of arbitrary matching were trained (e.g., AB and CD) but only one of those stimulus sets was trained in identity matching (e.g., AB). No evidence of emergent symmetry was found in Experiments 1 and 2. In Experiment 3, two pigeons showed moderate evidence of emergent symmetry, one pigeon showed suggestive evidence of emergent symmetry, and one pigeon did not show any evidence of emergent symmetry. In Experiment 4, two pigeons showed moderate evidence of emergent symmetry with the AB Stimulus Set (one of those pigeons also showed suggestive evidence of emergent symmetry with the CD Stimulus Set) and one pigeon did not show any evidence of emergent symmetry with either stimulus set. These data suggest that intermixing identity matching with the same stimuli used in arbitrary matching is a necessary, but not sufficient condition to obtaining emergent symmetry in pigeons.
284

Factors Affecting the Conditioned Reinforcing Strength of Stimuli in Differential Reinforcement of Other Behavior and Fixed-Time Schedules

Myers, Alexander M. 01 May 1978 (has links)
Two experiments were conducted in an attempt to provide a direct, response-independent test of the delay-reduction hypothesis of conditioned reinforcement. In both experiments, pigeons made observing responses, by pressing a treadle, for stimuli associated with the schedule component in effect . The consequences of an observing response were varied; an observing response produced: a) either the stimulus associated with the shorter component or the stimulus associated with the longer component depending on the schedule component in effect; b) the stimulus associated with the short component only; c) the stimulus associated with the long component only; or, d) neigher stimulus (no consequence). In Experiment I, naive pigeons were initially exposed to a mixed schedule with two differential reinforcement of other (ORO) behavior components; 10 seconds and 30 seconds (Phase One). In the second phase the same birds were exposed to an identical schedule, but the components were fixed time (FT) components (Phase Two). Reinforcement in both phases was six seconds access to food. In Experiment II, naive pigeons were exposed to both phases of Experiment I., but reinforcement density was altered. Each 10 second component was followed by 3 seconds of food and each 30 second component was followed by 9 seconds of food. In both experiments, differential observing behavior was maintained during the FT (Phase Two) procedure but not during the ORO (Phase One) procedure. In addition, equalizing reinforcement density (Experiment II) had the effect of altering the pattern of observing behavior but did not reverse or eliminate the preference shown for the stimulus associated with the shorter delay to reinforcement over the stimulus associated with the longer delay to reinforcement. It is suggested that some characteristic of the DRO procedure may have been responsible for the lack of differential observing. While the delay-reduction hypothesis of conditioned reinforcement was supported by the results of theFT procedure of both experiments, some amendments are required to account for the lack of differential observing during theDRO procedure. Reinforcement density appeared to have little effect upon observing behavior, but further research is advised concerning its effect upon observing response patterns.
285

Equine Operant Conditioning: Autoshaping, Observational Learning, and Discriminative Stimulus Intensity

Stewart, Paul H. 01 May 1992 (has links)
This thesis is compromised of three studies in which basic principles of operant conditioning were applied to horses. Autoshaping was examined as a method for horse training. Observational learning was investigated to confirm that naive horses can, in fact, acquire novel behavior by observing experienced horses, and the rate of acquisition with observation is more rapid than spontaneous responding without observation. A third study examined the effect of discriminative stimulus intensity on the acquisition rate of novel behavior. All subjects learned to use an operant conditioning device. Subjects in the first study autoshaped. Observational learning was also demonstrated to be a means by which horses can learn. The rate of learning was significantly improved through observation. Intensity of the discriminative stimulus affects the acquisition of novel behavior. The subject exposed to the higher intensity stimulus acquired sustained manipulandum pressing significantly faster than other subjects. It was concluded that horses acquire behavior in much the same manner as other species.
286

Evaluation Of A Presentation And Measurement Method For Assessing Activity Preference

Lieblein, Tara L 20 June 2003 (has links)
Much research has focused on the development of methods of measuring preference for stimuli. These methods have shown to be an accurate and valid way to identify potential reinforcers. However, these methods have only been conducted with tangible stimuli and have not been extended to non-tangible stimuli or activities, potentially because these types of stimuli are not appropriate for current preference assessment presentation methodologies. This study used a single stimulus presentation preference assessment to identify preferred activities for two adults with developmental disabilities. Two measures (duration of engagement and indices of happiness) were collected to identify preferred stimuli. For both participants, there were differences in happiness measure between activities. The engagement measure only produced differentiated results for one participant. Reinforcer assessments were conducted to determine if the measures of preference were able to identify high preference stimuli that functioned as more effective reinforcers more than stimuli identified as low preference. Both participants exhibited high rates of an arbitrary response during all conditions of the reinforcer assessment. Therefore, the reinforcer assessments did not validate the results of the preference assessments.
287

Os efeitos do atraso em tarefas de MTS sobre o estabelecimento de classes de equivalência e os parâmetros de fixação do olhar / The effects of delaye in MTS tasks on the establishment of equivalence classes and on the parameters of eye fixations

Vilela, Eduardo Cunha 22 January 2019 (has links)
Pesquisas apontam que o DMTS tem se mostrado mais eficaz no estabelecimento de classes de equivalência e maior grau de relacionamento entre estímulos de uma mesma classe do que o SMTS. Uma explicação possível para essas diferenças é que o aumento no intervalo de atraso entre a retirada do estímulo modelo e apresentação dos estímulos comparação em procedimentos de DMTS leva a uma maior exposição dos participantes ao estímulo modelo. Essa hipótese se alinha a resultados obtidos em experimentos que avaliam parâmetros de observação no estudo de discriminações condicionais, que demonstram que maiores durações de fixação do olhar sobre estímulos modelo estão associadas a maiores porcentagens de acerto no aprendizado em tarefas de MTS de identidade com modelos múltiplos. O presente estudo teve como objetivo avaliar os efeitos do emprego de atraso sobre a formação de classes e sobre parâmetros de fixação do olhar sobre os estímulos modelo em tarefas de MTS a partir do rastreamento dos olhos. Nove estudantes de graduação ou pós-graduação foram expostos a um treino de discriminações condicionais com estrutura OTM para estabelecer as classes A1B1C1, A2B2C2, A3B3C3 e A4B4C4. Cada uma dessas classes foi associada a uma condição de atraso durante o treino: simultânea, atrasos 0s, 2s e 4s respectivamente. Posteriormente, foram submetidos aos testes das relações emergentes de equivalência CB e BC, e simetria BA e CA em tentativas de DMTS com atraso 0s. Sete participantes atingiram o critério de aprendizagem durante o treino e conseguiram formar classes. Apesar de todos os participantes que atingiram os critérios terem aprendido primeiro relações de DMTS, não foram observados padrões ou diferenças significativas no aprendizado das discriminações condicionais ou formação de classes em nenhuma das condições. A análise dos parâmetros de observação também não revelou diferenças significativas entre frequência e duração de fixações do olhar sobre o modelo em nenhuma nas tentativas de SMTS ou DMTS com qualquer valor de atraso. Todavia, foi observado um efeito de prática, com valores maiores de duração de fixação nos blocos iniciais do treino. Esses resultados sugerem, portanto, que o maior tempo de exposição aos modelos não é suficiente para explicar as diferenças observadas no estabelecimento de classes de equivalência em tarefas de DMTS. Entretanto, alinham-se com a perspectiva de que um maior engajamento em comportamento de observação pode estar relacionado a um maior controle de estímulos dados os resultados do efeito de prática / Researches have indicated that the DMTS has been shown to be more effective in establishing equivalence classes and a higher degree of relationship between stimuli of the same class than SMTS. One possible explanation for these differences is that the increase in the delay interval between the withdrawal of the stimulus model and the presentation of the comparison stimuli in DMTS procedures leads to greater exposure of the participants to the stimulus model. This hypothesis aligns with results obtained in experiments that evaluate observation parameters in the study of conditional discriminations, which demonstrate that longer fixation durations on model stimuli are associated with higher percentages of learning success in multiple-models identity MTS tasks. The objective of the presente study was to evaluate the effects of the use of delay on the formation of classes and on parameters of fixation of the look on the model stimuli in MTS tasks from the eye tracking. Nine graduate or postgraduate students were exposed to conditional discrimination training with OTM structure to establish classes A1B1C1, A2B2C2, A3B3C3 and A4B4C4. Each of these classes was associated with a delay condition during training: simultaneous, delays 0s, 2s and 4s respectively. Subsequently, they were submitted to the tests of the emergent equivalence relations CB and BC, and symmetry BA and CA in attempts of DMTS with delay 0s. Seven participants reached the learning criterion during the training and were able to form classes. Although all participants who met the criteria first learned DMTS relationships, no significant patterns or differences in learning conditional discrimination or class formation were observed in any of the conditions. The analysis of the observation parameters also did not reveal significant differences between frequency and duration of fixations of the look on the model in any in the attempts of SMTS or DMTS in any with any value of delay. However, a practical effect was observed, with higher fixation duration values in the initial training blocks. These results suggest, therefore, that the greater time of exposure to the models is not enough to explain the differences observed in the establishment of equivalence classes in DMTS tasks. However, they are aligned with the view that greater engagement in observation behavior may be related to greater control of stimuli given the results of the effect of practice
288

Assessing the Effects of Derived Relational Responding on Intraverbal Use of Same-Opposite and More Than-Less Than Relations in Children with Autism

White, Jane P. 30 October 2014 (has links)
Relational Frame Theory provides an analysis of verbal behavior involving a focus on the development of relational operants which are seen as a basis for language. From this basis, a framework is provided for establishing relational networks in individuals who lack derived relational ability. Establishment of relational frames may increase the probability of responding relationally to novel instances and use of the specific relational frames during social interactions; therefore, training verbal relations in accordance with an RFT approach may enhance intraverbal responding and facilitate the emergence of untrained responses. The purpose of this study was to evaluate the emergence of specific relationships in the context of intraverbal responding as a collateral effect of training on relational networks in four children with Autism Spectrum Disorder. Two participants demonstrated mastery of derived relational responding (DRR) without training, one participant demonstrated mastery of DRR following training, and a fourth participant demonstrated mutual entailment and some combinatorial entailment. Increases in vocal verbal behavior during generalization probes were observed, although increased use of all target relations was not observed in all participants. Further research is needed to evaluate specific deficits in derived relational responding among individuals with ASD, as well as the correlation between DRR and language ability.
289

Contrasting reduced overshadowing and forward blocking

Wheeler, Daniel S. January 2006 (has links)
Thesis (Ph. D.)--State University of New York at Binghamton, Department of Psychology, 2006. / Includes bibliographical references.
290

Perceptual Organization in Vision: Emergent Features in Two-Line Space

January 2011 (has links)
What exactly are the "parts" that make up the whole object, and how and when do they group? The answer that is proposed hinges on Emergent Features: features that materialize from the configuration which make the object more discriminable from other objects. EFs are not possessed by any individual part and are processed as or more quickly than are the properties of the parts. The present experiments focus on visual discrimination of two-line configurations in an odd-quadrant task. RT data were obtained and compared with a prediction based on the number of EF differences in the odd quadrant (the higher the number of EF differences, the faster the discrimination was predicted). The results suggest that the EFs most responsible for the variations in RT might be lateral endpoint offset, intersections, parallelism, connectivity, number of terminators, and pixel count. Future directions include investigating the individual contributions and salience of EFs.

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