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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.
231

Efeito do ensino de palavras monossilábicas via treino de relações condicionais arbitrárias sobre o controle por unidades mínimas em leitura recombinativa / Effect of teaching monosyllabic words via arbitrary conditional relations on the minimal control units in recombinative reading

Ariene Coelho Souza 25 June 2009 (has links)
O procedimento de discriminação condicional Matching - to - Sample é utilizado em estudos que se propõem a investigar experimentalmente as relações envolvidas no ler e, mais especificamente, de verificar as possibilidades de emergência de novas relações a partir das que foram diretamente treinadas . No entanto, para uma leitura proficiente é necessário que o aprendiz esteja sob controle de unidades menores do que a palavra, a fim de que o comportamento de ler sob controle das unidades mínimas possa emergir. A maioria das pesquisas nesta área tem sido realizadas a partir do treino e teste recombinativo de palavras inteiras. A leitura sob controle das unidades mínimas, nestes estudos, é exibida geralmente depois do treino de pelo menos três conjuntos de palavras. O objetivo do presente trabalho foi investigar a possibilidade de um aumento na velocidade de aquisição do controle pelas unidades menores e redução da variabilidade no desempenho em leitura recombinativa partindo do treino direto de um repertório de quatro palavras monossilábicas. Foram feitos dois experimentos: no primeiro, participaram quatro crianças, com idades entre 3 anos e 10 meses e 5 anos. Os estímulos experimentais originais (conjunto ABC) foram NO, PE, PA e LU e os estímulos experimentais derivados (conjunto ABC) foram LUPA, PANO, PAPA e LULU. Os resultados demonstraram que os quatro participantes apresentaram variabilidade no desempenho e não houve emergência da leitura recombinativa para nenhum deles. Foi realizado então o segundo experimento a partir de manipulações de variáveis que possivelmente interferiram no desempenho dos participantes. Neste segundo experimento, participaram três crianças, das quatro que foram expostas ao experimento anterior. Os estímulos experimentais originais (conjunto ABC) foram BO, BA, LO e LA e os derivados (conjunto ABC) foram BOBA, BABO, LOLA e LALO. Como resultados, dois dos três participantes exibiram leitura recombinativa e a variabilidade no desempenho destes participantes se mostrou menor do que nos estudos anteriores. Concluiu-se desta forma, que a partição do estímulos é uma variável importante para a independência funcional das sílabas e posterior emergência da leitura recombinativa. Assim, o treino monossilábico se mostrou eficaz para aumentar a velocidade de aquisição e diminuir a variablidade no desempenho em leitura recombinativa para os participantes deste estudo. / The procedure of conditional discrimination Matching - to - Sample is used in studies that experimentally investigate the relationship involved in \"reading\" and, more specifically, examine the possibilities of emergence of new relationships from which they were directly trained. However for a proficient reading it is necessary to read under control of smaller units than the word, so that the reading behavior under the control by minimal units could emerge. The majority of researches in this area have been carried out with training and recombinative testing of the whole words. Reading behavior under control by the minimal units in these studies generally appears after the training of at least three sets of words. The objective of this study therefore was to investigate the possibility of an increase in speed of acquisition of control by smaller units and to reduce variabilitys performance in recombinative reading through the direct training of a repertoire of four monosyllabic words. Two experiments were conducted: in the first one, four children were from three years and ten months old to five years old. The originals experimental stimuli (all ABC) was NO, PE, PA and LU and the deriveds experimental stimuli (all A\'B\'C \') were LUPA, PANO, PAPA and LULU. The results showed that all four participants showed variability in performance and no emergence of recombinative reading . A second experiment were carried out withthe manipulation of variables that possibly interfered in the performance of the participants. In this second experiment three children were involved, four of which were exposed to the previous experiment. The original experimental stimuli (all ABC) were BO, BA, LA and LO and derived (all A\'B\'C \') were BABO, BOBA, LALO and LOLA. As a result, two of the three participants showed recombinative reading and the variability in performance of these participants wassmaller than in previous studies. The partition of the stimulus was considered an important variable for the functional independence of syllables and subsequent emergence of recombinative reading. Thus, the monosyllabic training was effective to increase the speed of acquisition and to reduce the variability in performance of recombinative reading for participants.
232

Efeitos de diferentes contingências de reforço no estabelecimento de discriminações condicionais e na formação de classes de estímulos equivalentes / Effect of different reinforcement contingencies on conditional discrimination acquisition and equivalence class formation

Paulo Sergio Dillon Soares Filho 15 October 2014 (has links)
As classes de equivalência de estímulos são produto das contingências de reforço. No entanto, as pesquisas têm utilizado apenas contingências de reforço positivo e investigado, na sua maioria, como eventos relacionados a um mesmo reforçador podem passar a compor uma mesma classe. O objetivo do presente trabalho foi avaliar o efeito de diferentes contingências de reforço, positivo e negativo, no estabelecimento de discriminações condicionais na formação de classes de equivalência em humanos. Foram realizados dois experimentos. No Experimento I, 12 participantes treinaram simultaneamente 12 relações condicionais (AB e BC) utilizando três arranjos de contingência de reforçamento diferentes: reforçamento positivo (Ganhar/Manter), reforçamento negativo (Manter/Perder) e uma contingência mista de reforçamento negativo e positivo (Ganhar/Perder), seguidos de testes de formação de classes de equivalência. No Experimento I, os participantes expostos aos testes de equivalência acertaram todas as tentativas de teste. Estes resultados demonstram a possibilidade de formação de classes de equivalência em uma contingência de reforço negativo, porém um possível efeito de teto impede a comparação de cada contingência na formação de classes. No Experimento II, sete participantes foram expostos ao treino de 12 relações condicionais, com classes com um maior número de nódulos (AB, BC e CD) utilizando apenas duas contingências de reforço (Ganhar/Manter e Manter/Perder). Em ambos os experimentos, a sequência de aquisição das discriminações e o viés inicial produzido pelas contingências de reforço negativo sugerem um impacto diferencial da punição em relação ao reforçamento. Os resultados nos testes de equivalência sugerem que a formação de classes é menos provável quando utilizada uma contingência de reforço negativo em relação a de reforço positivo. Foi discutida a generalidade da formulação sobre formação de classes de equivalência, priorizando os padrões de controle de estímulos produzido pelas diferentes contingências. Ressalta-se a necessidade de maior investigação sobre quais os efeitos do uso de contingências aversivas no controle da resposta e mais especificamente no controle de estímulos / Equivalence classes are produced by reinforcement contingencies, however, research have used exclusively positive reinforcement and investigated mostly how events related to a same reinforcer may result in the formation a same class. The aim of this study was to evaluate how different reinforcement contingencies affect the acquisition of conditional discriminations and equivalence class formation in humans. Two experiments were conducted. In Experiment I, 12 participants learned 12 conditional relations (AB BC) under three different contingencies: positive reinforcement (Gain/Maintain), negative reinforcement (Maintain/Lose) and a mixed contingency (Gain/Lose). Equivalence class test were applied subsequently. In Experiment I, participants that underwent the equivalence tests performed correctly in all trials, although a roof effect might have prevented a proper comparison of the contingencies effect. In Experiment II, seven participants learned 12 conditional relations with more nodes (AB, BC e CD) and two reinforcement contingencies (Gain/Maintain and Maintain/Lose). In both experiments, the conditional discrimination acquisition sequence and the initial bias produced by the negative reinforcement contingency suggest a differential effect of punishment in relation to reinforcement. The equivalence test results suggest the possibility of equivalence class formation using a negative reinforcement contingency and indicate that equivalence classes are less probable using a negative reinforcement contingency than a positive reinforcement one. The generality of the equivalence class formulation was discussed emphasizing the investigation of stimuli control patterns produced by the contingencies. The lack of knowledge about stimulus control produced by aversive contingencies was highlighted
233

Variáveis relevantes para a emergência de simetria em pombos em procedimento de matching-to-sample sucessivo / Relevant variables for emergence of symmetry in pigeons in successive matching-to-sample procedure

Viviane Verdu Rico 07 May 2010 (has links)
Treinos discriminativos específicos podem favorecer que um organismo responda consistentemente sob controle de relações entre estímulos que não foram diretamente ensinadas. Diz-se, então, que estas são relações emergentes. Caso tais relações estejam de acordo com as propriedades de reflexividade, simetria e transitividade, é constatada a formação de classes de estímulos equivalentes. Nas últimas décadas, diversos estudos vêm tentando demonstrar a formação de classes de estímulos equivalentes em animais não humanos, mas poucos têm tido sucesso. Dentre as propriedades definidoras da equivalência, a simetria tem sido a mais difícil de ser observada. Ao identificarem variáveis relacionadas aos resultados inconsistentes de estudos envolvendo testes de simetria, Frank e Wasserman (2005) planejaram um experimento com pombos, no qual tentativas de relações de identidade e arbitrárias eram apresentadas em uma mesma sessão, que resultou em desempenho positivo nos testes. O objetivo do presente trabalho foi identificar algumas das variáveis que possivelmente contribuíram para os resultados obtidos no referido estudo. Para tanto, foram realizados dois experimentos, com três pombos cada, para verificar: 1) a replicabilidade dos dados obtidos por Frank e Wasserman (2005); 2) se o treino de reversibilidade de combinações negativas é um fator importante na obtenção de simetria emergente com este procedimento. Os sujeitos foram ensinados a bicar estímulos apresentados isoladamente na tela de um computador em uma tarefa de matching sucessivo. O Experimento I consistiu no treino misto das relações AA, BB e AB e no teste de simetria BA. O Experimento II era semelhante ao anterior, exceto que, para que não ocorresse o treino de reversibilidade das combinações negativas, foram acrescentadas as relações CC no treino. Apenas dois pombos, um de cada experimento, apresentaram responder discriminado no treino. Ambos apresentaram desempenho semelhante ao do estudo de Frank e Wasserman (2005), o que indicaria emergência de simetria. Entretanto, uma análise mais detalhada do desempenho destes dois pombos revelou um responder instável entre as sessões de teste. Os outros quatro sujeitos não apresentaram responder discriminado apesar do elevado número de sessões (entre 65 e 220). A análise da distribuição das respostas ao longo do tempo de apresentação dos estímulos indicou diferenças entre o responder dos pombos que concluíram e que não concluíram o treino. Estes últimos apresentaram um responder marcado por longas pausas entre respostas, com menor freqüência de respostas para o estímulo modelo. Os pombos que concluíram a fase de treino apresentaram um responder constante, com poucas e curtas pausas, com maior freqüência de respostas diante do modelo do que diante dos estímulos de comparação. Os resultados dos testes de simetria indicam que o treino de reversão das combinações negativas não foi um fator relacionado à emergência de simetria com este procedimento. O fato de que a maioria dos sujeitos não aprendeu as relações treinadas, bem como os diferentes padrões de responder apresentados pelos sujeitos ao longo do treino e o desempenho instável nas sessões de teste, indicam a necessidade de refinamento do procedimento, buscando favorecer a aprendizagem e produzir estabilidade nos testes / Specific conditions in the discriminative training should set conditions for an organism to respond controlled by stimuli relations, not directly trained. These stimuli relations are said to be emergent. If these relations are reflexive, symmetric and transitive, than classes of equivalent stimuli were established. In the last decades, several studies tried to demonstrate the formation of equivalence classes in non-humans animals, but a few succeed. From among those properties that define equivalence relations, symmetry is the most hardly observed. Once identified some variables involved with the discrepant results in the symmetry tests, Frank and Wasserman (2005) designed an experiment with pigeons, where identity and arbitrary trials were presented altogether in the training sessions. This procedure resulted in positive outcomes in symmetry tests. The purpose in this study was to assess some of the variables that possibly contributed to Frank and Wassermans (2005) positive results. Two experiments were conducted in order to verify 1) Frank and Wasserman (2005) data replicability; 2) if training the negative combinations reversals is relevant in producing emergent symmetry by this procedure. Tree pigeons participated in each one of them. The pigeons were trained to peak stimuli presented alone in a computer screen in a successive matching task. Experiment I consisted in mixed training of AA, BB and AB relations followed by symmetry tests for BA relation. Experiment II was identical to the previous one, except that CC relations were added in order to avoid the negative relations reversal training. Only two pigeons, one of each experiment, reach training criterion. Their performances in symmetry tests were quite similar to those presented by Frank and Wasserman (2005) indicating that training resulted in symmetry relations. Meanwhile, a careful analysis of these symmetric performances in the testes revealed to be unstable from session to session. The four remaining pigeons did not reached training criterion despite of been exposed to high number of training sessions (about 65 to 220 sessions). Differences in distribution of responses over stimuli presentation interval were observed comparing data of the two pigeons that reached training criterion and pigeons that did not reach training criterion. Low frequency of response and long inter-response interval to the sample stimulus characterized the performances of the four pigeons whose training criterion has never been reached. For the pigeons whose training criterion was reached the responses occurred constantly, with few and short inter-responses intervals and high frequency of responding to the sample stimulus when compared to the comparison stimulus. The symmetry tests results suggests that training the negative combinations reversals did not affected the emergence of symmetric relations in this procedure. The fact that most of the pigeons did not reached training criterion, along with the different response patterns shown by each pigeon in the training task and the unstable performance observed in the tests indicates that procedure refining is needed in order to improve learning to criterion and produce stability during tests.
234

”Alla tolkar detta olika liksom” : Hur lärare i ämnet Idrott och Hälsa arbetar med bedömning, betyg och likvärdighet / “Everyone interprets this in like different ways” : How teacher’s in Physical education work with assessment, grades and equivalence

Forsgren, Kalle Gunnar January 2019 (has links)
Föreliggande studies syfte var att undersöka hur lärare i ämnet Idrott och Hälsas syn- och tillvägagångssätt vid bedömning samt betygssättning påverkar likvärdigheten i ämnet på gymnasiet. Studiens teoretiska ramverk utgår från Aaron Antonovskys KASAM och dess tre centrala begrepp; Begriplighet, Hanterbarhet och Meningsfullhet. Det empiriska materialet har samlats in genom kvalitativa djupintervjuer med sex lärare i ämnet Idrott och Hälsa. Resultatet visar att det förekommer olikheter bland lärarna vid exempelvis deras syn på likvärdighet, tolkningar av styrdokumenten och vilka arbetsmetoder som föreligger vid bedömning och betygssättning. Studiens slutsats är att läroplanens tolkningsbarhet skapar ett krav på lärarens subjektiva omdöme. Tolkningarnas differenser leder till icke-likvärdiga villkor för eleverna vid bedömning och betygssättning i ämnet Idrott och Hälsa. / The purpose of the present study was to examine how teachers in Physical education sees and approaches the work of assessment and grading and how that affects the equivalence in the subject. The theoretical framework of the study is based on Aaron Antonovskys SOC and its three key concepts; Comprehensibility, manageability and meaningfulness. The empirical material has been collected through qualitative in-depth interviews with six teachers in Physical education. The result shows that there are differences among the teachers in, for example, their perspective of equivalence, their interpretations of the curriculum and which working methods they are using when assessing and grading. The study’s conclusion is that the curriculum’s interpretability creates a requirement for the teacher’s subjective opinion. The differences between the interpretations leads to non-equivalent conditions for the students in the assessment- and grading process in Physical education.
235

Traduire la culture caribéenne. Étude comparative des proverbes créoles de la caraïbe francophone et de leurs équivalents dans la Caraïbe anglophone / Translating Caribbean culture. A comparative analysis of Francophone Caribbean proverbs and their Anglophone Caribbean equivalents

Bogle, Desrine 26 October 2012 (has links)
Malgré la diversité des territoires qui constituent la région caribéenne, sur le plan linguistique, ils ont en commun une même culture, celle de la créolité. Dans cette perspective, cette étude se propose d’étudier la synergie linguistique qui ressortirait d’une comparaison des proverbes créoles de la Caraïbe francophone et anglophone. Outre la question, parfois controversée, de l’origine des proverbes, l’objectif principal sera de trouver les convergences et les superpositions, tous les rapprochements entre les proverbes, le rôle joué par la littérature dans leur conservation et leur transmission intra et inter-linguistique et d’observer les modifications qu’ils ont pu subir. L’étude de l’impact de la mondialisation sur la traduction des textes de la Caraïbe, qui appartiennent à une tradition d’oralité, permettra de comprendre les phénomènes de transmission. Loin de se situer en opposition à la théorie Bermanienne sur la destruction des réseaux vernaculaires, ce travail visera à démontrer que la traduction des proverbes créoles dans le cadre même de la créolité offre justement la solution la plus en adéquation dans sa dimension culturelle, celle qui permet de les maintenir dans leur territorialité. / Despite the diversity of the Caribbean territories, they all share the same culture: Creoleness. In light of this, the present research proposes to study the linguistic synergy that is evident in a comparative study of Creole proverbs from the francophone and Anglophone Caribbean. Apart from the controversial issue of the origin of these proverbs, the main aim is to find the convergent points as well as any relationships between the proverbs, the role that literature plays in their preservation and their intra- and inter-linguistic transmission. A study of the impact of globalization on the translation of Caribbean texts, which are a part of oral tradition, will help to understand the phenomena underlining their transmission. Not aiming to contradict Berman’s theory on the destruction of vernacular links, this work will try to show that translating Creole proverbs in the context of Creoleness offers the best possible solution in light of cultural and regional factors.
236

Operator algebras, matrix bundles, and Riemann surfaces

McCormick, Kathryn 01 August 2018 (has links)
Let $\overline{R}$ be a finitely bordered Riemann surface, and let $\mathfrak{E}_\rho(\overline{R})$ be a flat matrix $PU_n(\mathbb{C})$-bundle over $\overline{R}$. Let $\Gamma_c(\overline{R}, \mathfrak{E}(\overline{R}))$ denote the $C^*$-algebra of continuous cross-sections of $\mathfrak{E}(\overline{R})$, and let $\Gamma_h(\overline{R},\mathfrak{E}(\overline{R}))$ denote the subalgebra consisting of the continuous holomorphic sections, i.e.~the continuous cross-sections that are holomorphic on the interior of $\overline{R}$. The algebra $\Gamma_c(\overline{R}, \mathfrak{E}(\overline{R}))$ is an example of an $n$-homogeneous $C^*$-algebra, and the subalgebra $\Gamma_h(\overline{R},\mathfrak{E}(\overline{R}))$ is the principal object of study of this thesis. The algebras $\Gamma_h(\overline{R},\mathfrak{E}(\overline{R}))$ appeared in the earlier works \cite{Abrahamse1976} and \cite{Blecher2000}. Operators that can be viewed as elements in $\Gamma_h(\overline{R},\mathfrak{E}(\overline{R}))$ are the subject of \cite{Abrahamse1976}. The Morita theory of $\Gamma_h(\overline{R},\mathfrak{E}(\overline{R}))$, under the guise of a fixed-point algebra and in the special case of an annulus $R$, is studied in \cite[Ex.~8.3]{Blecher2000}. This thesis studies these algebras and their topological data $\mathfrak{E}_\rho(\overline{R})$ motivated by several problems in the theory of nonselfadjoint operator algebras. Boundary representations are an invariant of operator algebras that were introduced by Arveson in 1969. However, it took nearly 50 years to show that boundary representations existed in sufficient abundance in all cases. I show that every boundary representation of $\Gamma_c(\overline{R}, \mathfrak{E}(\overline{R}))$ for $\Gamma_h(\overline{R}, \mathfrak{E}(\overline{R}))$ is given by evaluation at some point $r \in \partial R$. As a corollary, the $C^*$-envelope of $\Gamma_h(\overline{R},\mathfrak{E}(\overline{R}))$ is $\Gamma_c(\partial R, \mathfrak{E}(\partial R))$. Using the $C^*$-envelope, I show that for certain choices of fibre and base space, $\Gamma_h(\overline{R}, \mathfrak{E}_\rho(\overline{R}))$ is not completely isometrically isomorphic to $A(\overline{R})\otimes M_n(\mathbb{C})$ unless the representation $\rho$ is the trivial representation. I also show that $\Gamma_h(\overline{R},\mathfrak{E}(\overline{R}))$ is an Azumaya over its center. Azumaya algebras are the ``pure-algebra'' analogues to $n$-homogeneous $C^*$-algebras \cite{Artin1969}. Thus the structure of the nonselfadjoint subalgebra $\Gamma_h(\overline{R},\mathfrak{E}(\overline{R}))$ reflects some of the structure of its $C^*$-envelope (which is $n$-homogeneous). Finally, I answer a question raised in \cite[Ex.~8.3]{Blecher2000} on the $cb$ and strong Morita theory of $\Gamma_h(\overline{R},\mathfrak{E}_\rho(\overline{R}))$, showing in particular that $\Gamma_h(\overline{R},\mathfrak{E}_\rho(\overline{R}))$ is $cb$ Morita equivalent to its center $A(\overline{R})$. As suggested in \cite[Ex.~8.3]{Blecher2000}, I provide additional evidence that $\Gamma_h(\overline{R},\mathfrak{E}_\rho(\overline{R}))$ may not be strongly Morita equivalent to its center. This evidence, in turn, suggests that there may be a Brauer group -like analysis for these algebras.
237

Překlad povídky J. D. Salingera Dokonalý den pro banánové rybičky. Lingvostylistická analýza / J. D. Salinger's "A Perfect Day for Bananafish" Translation. Linguo-stylistic Analysis

Válková, Veronika January 2019 (has links)
This thesis aims to analyse several translations of J.D. Salinger's short story A Perfect Day for Bananafish: namely two translations and two edited versions of the latter one. The contrastive view is used to discern the main differences in meaning of the original and the translated texts. There are several points of view adopted to recognise the differences. On the syntactic level, the contrast between the texts was found to be present in the treatment of the author's style, predominantly in the narrative perspective. Not employing nominal structures a great deal, the author's style was not lost in the translation process. Comparing the translated texts, a tendency to adhere to the syntactic surface structure of the original text was found in the less recent versions. Another level of analysis explored the temporal relations of the texts, with the original text relying mostly on structures expressing sequences of events and also simultaneity of events, but not the perfective aspect to a great degree. These time relations are also found to be communicated in the translated texts successfully. It is not only the narrator that is discussed in this thesis, as a great portion of the short story consist of dialogues. The analysis aimed, using certain excerpts of the story, to find to what degree...
238

An analysis of zero equivalence in the translation of scientific terms from English into Northern Sotho

Ngobeni, Mkateko Melidah January 2013 (has links)
Thesis (M.A. (African Languages)) --University of Limpopo, 2013 / This study entails the translation of scientific terms from English into Northern Sotho. The reason one conducted this study is because translators experience difficulties in finding the correct equivalent terms, especially in Northern Sotho. Consequently, borrowing and transliteration of terms becomes their last resort. However, that does not help users of dictionaries to achieve their communicative goal. The study highlights that, the borrowing of terms leads to language shift and death as users no longer consider other equivalents. In addition, the study indicates that the constant usage of the borrowed terms causes the terms to lose meaning and function. The way in which people translate idiomatic expressions is a huge problem as well. Mostly, people end up using literal translation and subsequently, the whole meaning of a text is lost or misunderstood.
239

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.
240

An Investigation of the Five-Term Contingency and the Conditional Control of Equivalence Relations

Serna, Richard W. 01 May 1987 (has links)
In recent years, there has been an increasing interest in the study of human operant behavior. One area of study reflecting this interest is the study of the formation of equivalent classes of stimuli by human subjects. The focus of the present research was the study of the conditions under which classes of equivalent stimuli can be inferred to be under conditional control. In Experiment 1-A, three college students were trained to respond to a balanced five-term contingency via a visual-visual simultaneous matching-to-sample task with two choices of comparison stimuli. Probe tests showed that subjects' behavior could be described as being controlled by positive and negative stimulus relations. When the second-order stimulus was removed during subsequent probes, none of the three subjects demonstrated strong correct responses to the four-term unit relations. Also, none of the three subjects demonstrated the expected transitive relations when the second-order (five-term) stimulus was removed. In Experiment 1-B--with the same three subjects--explicit training of the four-term unit relations showed the expected transitive relations in the absence of the second-order stimulus. In Experiments 2 through 5--using a matching-to-sample task similar to that used in Experiments 1-A and 1-B--five subjects were trained to respond to comparison stimuli C and E in the presence of sample A and second-order stimulus X and to comparison stimuli Band Fin the presence of sample D and second-order stimulus X. Likewise, the subjects were trained to respond to comparison stimuli Band Fin the presence of sample A and second-order stimulus Y and to comparison stimuli C and E in the presence of sample D and second-order stimulus Y. Probe tests for transitive relations showed that four of the five subjects eventually demonstrated four three-member classes of equivalent stimuli that functioned separately under the control of the second-order stimuli. The four subjects demonstrating the classes of equivalent stimuli either a) demonstrated the transitive relations immediately orb) demonstrated the transitive relations after explict retraining of the underlying four-term unit relations. The results of all experiments together indicated that the composition of classes of equivalent stimuli can be conditionally controlled by either a) removing the second-order stimulus orb) training subjects to respond to classes of equivalent stimuli under the control of other explicit visual second-order stimuli. The results are discussed in terms of verbal behavior, emergent behavior, and conceptual development.

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