The purpose of this study was to examine the use of instructional design when considering the principles of cognitive load theory in traditional classroom instruction. The treatment group (N=31) was designed with a focus on two principles of cognitive load theory—multiple representation and contiguity. The multiple representation principle included text and pictures rather than spoken words and contiguity presented words and pictures simultaneously through multimedia video. The control group (N=26) did not focus on cognitive load theory principles and was discussion or text only—no multimedia video. This study was conducted using a pretest and posttest control group design and demographic survey. The participants consisted of students from an undergraduate computer applications class that was used to meet computer literacy requirements. The same instructor taught both instructional design methods in the traditional classroom setting. The major finding that there was a significant difference in achievement based on the instruction mode (integration of video vs. no integration of video) was constant across all variables in favor of the treatment group. Again, the control group had a mean posttest score of 80.58, and the treatment group had a mean posttest score of 84.48. The groups were significantly different based on the posttest exam, t = 3.28, p < .01. The treatment group scored significantly higher than the control group. The research also examined the relationships among the posttest scores and the various demographic variables. No meaningful relationships were identified. All associations were in the very low (less than .20) or low (.20-.39) level.

No description available.

Doctor of Philosophy (Phd) / Despite an abundance of evidence demonstrating that the temporal relationship between events is a key factor in an organism learning an association between those events, a general theoretical account of temporal contiguity has remained elusive. A particular question that has received little attention is whether behaviour established with strong contiguity can be maintained when contiguity is weakened. The primary aims of this thesis were to examine the mechanisms underlying both the effects of contiguity on learning in rats and humans and the maintenance effect described above. The experiments reported in this thesis demonstrated that rats’ lever-pressing for food/sucrose acquired with immediate reinforcement persisted when a trace/delay that would have prevented acquisition was subsequently introduced, provided the lever was a valid signal for reinforcement. In classical conditioning with a 10-second trace, rats performed magazine-entry during lever-insertion (goal-tracking) instead of lever-pressing (sign-tracking); with zero-trace, rats both sign- and goal-tracked if lever-insertion time was 10 seconds, while goal-tracking dominated with 5-second lever-insertion time. Furthermore, while it was found that context-US associations may interfere with CS-US learning, context conditioning did not contribute to the retardation of sign-tracking in trace conditioning. Overall, these results are consistent with the theory that a localisable manipulandum that signals an appetitive outcome with strong contiguity acquires hedonic value, and that such hedonic value drives lever-pressing behaviour that is resistant to changes in the conditions of reinforcement. Human performance in a conditioned suppression task was inversely related to trace interval, but this apparent contiguity effect was at least partially mediated by the number of distractors during the trace interval, as predicted by Revusky’s concurrent interference theory. Furthermore, some transfer of conditioned suppression was observed when the trace was subsequently lengthened. Despite the different explanations proposed to account for rat and human performance in these experiments, the results suggest that the effects of contiguity on learning may be driven by similar underlying mechanisms across species.

We consider weak convergence of a sequence of asset price models (Sn) to a limiting asset price model S. A typical case for this situation is the convergence of a sequence of binomial models to the Black-Scholes model, as studied by Cox, Ross, and Rubinstein. We put emphasis on two different aspects of this convergence: firstly we consider convergence with respect to the given "physical" probability measures (Pn) and secondly with respect to the "risk-neutral" measures (Qn) for the asset price processes (Sn). (In the case of non-uniqueness of the risk-neutral measures also the question of the "good choice" of (Qn) arises.) In particular we investigate under which conditions the weak convergence of (Pn) to P implies the weak convergence of (Qn) to Q and thus the convergence of prices of derivative securities. The main theorem of the present paper exhibits an intimate relation of this question with contiguity properties of the sequences of measures (Pn) with respect to (Qn) which in turn is closely connected to asymptotic arbitrage properties of the sequence (Sn) of security price processes. We illustrate these results with general homogeneous binomial and some special trinomial models. (author's abstract) / Series: Report Series SFB "Adaptive Information Systems and Modelling in Economics and Management Science"

Doctor of Philosophy (Phd) / Despite an abundance of evidence demonstrating that the temporal relationship between events is a key factor in an organism learning an association between those events, a general theoretical account of temporal contiguity has remained elusive. A particular question that has received little attention is whether behaviour established with strong contiguity can be maintained when contiguity is weakened. The primary aims of this thesis were to examine the mechanisms underlying both the effects of contiguity on learning in rats and humans and the maintenance effect described above. The experiments reported in this thesis demonstrated that rats’ lever-pressing for food/sucrose acquired with immediate reinforcement persisted when a trace/delay that would have prevented acquisition was subsequently introduced, provided the lever was a valid signal for reinforcement. In classical conditioning with a 10-second trace, rats performed magazine-entry during lever-insertion (goal-tracking) instead of lever-pressing (sign-tracking); with zero-trace, rats both sign- and goal-tracked if lever-insertion time was 10 seconds, while goal-tracking dominated with 5-second lever-insertion time. Furthermore, while it was found that context-US associations may interfere with CS-US learning, context conditioning did not contribute to the retardation of sign-tracking in trace conditioning. Overall, these results are consistent with the theory that a localisable manipulandum that signals an appetitive outcome with strong contiguity acquires hedonic value, and that such hedonic value drives lever-pressing behaviour that is resistant to changes in the conditions of reinforcement. Human performance in a conditioned suppression task was inversely related to trace interval, but this apparent contiguity effect was at least partially mediated by the number of distractors during the trace interval, as predicted by Revusky’s concurrent interference theory. Furthermore, some transfer of conditioned suppression was observed when the trace was subsequently lengthened. Despite the different explanations proposed to account for rat and human performance in these experiments, the results suggest that the effects of contiguity on learning may be driven by similar underlying mechanisms across species.

<p>This essay deals with subject-verb concord in written compositions by Swedish students at Uppsala University. The essay investigates the possibility that students who continue studying English beyond the A level at the university make fewer errors than students who do not continue.</p><p>In order to minimize the influence of the students’ gender and first language, only essays written by female students were included in the study; in addition, all students included had Swedish as their first language, and so did their parents. 25 essays by students who continued their studies and 25 essays by students who may not have done so were chosen. All 50 essays were examined for both correct and incorrect instances concerning concord between subjects and verbs in the present tense. The primary verbs to be, to do and to have were analysed as well as regular and irregular verbs.</p><p>The results show that the 25 students who continued beyond the A level made fewer errors than the 25 students who may not have continued. The results also indicate that subject-verb concord is not a serious problem for Swedish learners.</p>

Nos estudos do desamparo aprendido em humanos os resultados experimentais tem sido inconsistentes. Isso provavelmente devido a ocorrencia, na sessao de incontrolabilidade, entre outras variaveis, de contiguidades sistematicas entre o termino do estimulo aversivo e a resposta imediatamente precedente, mimetizando uma condicao de controle, embora acidental. Com o objetivo geral de estabelecer um procedimento que permitisse controle experimental suficiente para que fosse analisado o efeito de uma historia de incontrolabilidade sobre a aprendizagem de uma nova resposta operante em sujeitos humanos, bem como a prevencao (imunizacao) desse efeito, foram realizados tres experimentos. O primeiro deles demonstrou o controle operante sob tres contingencias de reforcamento negativo (sequencias variaveis, labirinto e discriminacao de formas geometricas), o que permitiu verificar o efeito da ausencia de controle sobre uma nova aprendizagem operante (Experimento 2 desamparo aprendido) e o efeito da ausencia de controle, apos historia de controle, sobre uma nova aprendizagem operante (Experimento 3 imunizacao). No Experimento 2, dois grupos de participantes foram expostos a sons aversivos (Grupos C e I) e um nao foi manipulado (Grupo N). Para os participantes do Grupo C, a interrupcao de um som agudo era contingente a emissao de sequencias variaveis; para os participantes do Grupo I, a duracao do som era independente das respostas emitidas. Os sujeitos do Grupo Incontrolavel foram divididos em dois subgrupos de acordo com a presenca ou a ausencia de indicacoes na tela (Ip e I). Na sessao de incontrolabilidade foram manipuladas algumas variaveis a fim de evitar a selecao acidental da resposta mensurada (duracao do estimulo; numero de tentativas; custo da resposta e instrucao inicial). Apos essa fase, todos os participantes foram submetidos a uma contingencia de resolucao de um labirinto associado a um som. No Experimento 3, um Grupo Precontrole (P) foi acrescido a triade do Experimento 2. A contingencia de fuga discriminação foi realizada na fase pre-tratamento sendo associada a um som. Na fase de teste os participantes dos Grupos C, N e P apresentaram menor latencia e maior numero de respostas corretas em comparacao aos grupos incontrolaveis. Entre esses ultimos, foi verificada uma correlacao negativa entre a frequencia de contiguidades no tratamento e o desempenho no teste. Os participantes do Grupo I apresentaram baixa frequencia de contiguidades no tratamento e latencias e falhas mais elevadas no teste; os do Grupo Ip mostraram padrao intermediario. Esses resultados replicam o desamparo aprendido e a imunizacao desse efeito em humanos, sugerindo que os pocedimentos estabelecidos foram adequados para o estudo desses dois efeitos e demonstram o papel da selecao acidental, durante a sessao de incontrolabilidade, como impeditivo da verificacao do efeito no teste (Grupo Ip). O papel das indicacoes na tela, os parametros utilizados e a presenca de contiguidades sistematicas foram discutidos / The results of learned helplessness studies with humans have been inconsistent. This is probably due to the systematic contiguity between the end of the aversive stimulus and the immediately preceding response during the uncontrollability session, which mimics an accidental control condition. Three experiments were conducted to establish a procedure with adequate experimental control to analyze the effects of an uncontrollability history upon learning of a new operant response in humans, as well as the prevention (immunization) of this effect. The first experiment demonstrated operant control under three negative reinforcement contingencies (variable sequences, maze, and discrimination of geometric forms), which allowed verifying the effect of the absence of control upon learning of a new operant response (Experiment 2 learned helplessness) and the effect of the absence of control, after a history of controllability, upon learning of a new operant response (Experiment 3 immunization). During the uncontrollability session, a number of variables were manipulated to avoid the accidental selection of the response being measured (duration of the stimulus, number of trials, response cost, and initial instructions). In Experiment 2, two groups were exposed to aversive tones (groups C and U) and one group was not (group N). For group C, the interruption of a high-pitch tone was contingent on the emission of variable sequences; for group U, the duration of the tone was response independent. Group U was further divided into two subgroups, according to the presence or absence of a hint on the screen (Up and U). After this manipulation, all participants had to solve a maze that was presented along with a tone. In Experiment 3, a pre-control group (P) was added to the ones in Experiment 2. The escape contingency for discriminating geometric forms was presented in the pre-treatment phase along with a tone. The results of the test phase indicated shorter latencies and a greater number of responses for groups C, N, and P, in comparison to the uncontrollable groups. For the latter groups, there was a negative correlation between the frequency of contiguities in the treatment phase and performance during the test phase. There was a low frequency of contiguities during treatment, and longer latencies and more errors during the test for Group U; an intermediate pattern was observed for Group Up. These results replicate the learned helplessness and immunization effects in humans, and suggest that this procedure is adequate to study these phenomena. The results also indicate that accidental selection during the uncontrollability session may eliminate the learned helplessness effect during the test (Group Up). The effects of the hints on the screen, the schedule parameters, and the presence of systematic contiguities are further discussed

Nos estudos do desamparo aprendido em humanos os resultados experimentais tem sido inconsistentes. Isso provavelmente devido a ocorrencia, na sessao de incontrolabilidade, entre outras variaveis, de contiguidades sistematicas entre o termino do estimulo aversivo e a resposta imediatamente precedente, mimetizando uma condicao de controle, embora acidental. Com o objetivo geral de estabelecer um procedimento que permitisse controle experimental suficiente para que fosse analisado o efeito de uma historia de incontrolabilidade sobre a aprendizagem de uma nova resposta operante em sujeitos humanos, bem como a prevencao (imunizacao) desse efeito, foram realizados tres experimentos. O primeiro deles demonstrou o controle operante sob tres contingencias de reforcamento negativo (sequencias variaveis, labirinto e discriminacao de formas geometricas), o que permitiu verificar o efeito da ausencia de controle sobre uma nova aprendizagem operante (Experimento 2 desamparo aprendido) e o efeito da ausencia de controle, apos historia de controle, sobre uma nova aprendizagem operante (Experimento 3 imunizacao). No Experimento 2, dois grupos de participantes foram expostos a sons aversivos (Grupos C e I) e um nao foi manipulado (Grupo N). Para os participantes do Grupo C, a interrupcao de um som agudo era contingente a emissao de sequencias variaveis; para os participantes do Grupo I, a duracao do som era independente das respostas emitidas. Os sujeitos do Grupo Incontrolavel foram divididos em dois subgrupos de acordo com a presenca ou a ausencia de indicacoes na tela (Ip e I). Na sessao de incontrolabilidade foram manipuladas algumas variaveis a fim de evitar a selecao acidental da resposta mensurada (duracao do estimulo; numero de tentativas; custo da resposta e instrucao inicial). Apos essa fase, todos os participantes foram submetidos a uma contingencia de resolucao de um labirinto associado a um som. No Experimento 3, um Grupo Precontrole (P) foi acrescido a triade do Experimento 2. A contingencia de fuga discriminação foi realizada na fase pre-tratamento sendo associada a um som. Na fase de teste os participantes dos Grupos C, N e P apresentaram menor latencia e maior numero de respostas corretas em comparacao aos grupos incontrolaveis. Entre esses ultimos, foi verificada uma correlacao negativa entre a frequencia de contiguidades no tratamento e o desempenho no teste. Os participantes do Grupo I apresentaram baixa frequencia de contiguidades no tratamento e latencias e falhas mais elevadas no teste; os do Grupo Ip mostraram padrao intermediario. Esses resultados replicam o desamparo aprendido e a imunizacao desse efeito em humanos, sugerindo que os pocedimentos estabelecidos foram adequados para o estudo desses dois efeitos e demonstram o papel da selecao acidental, durante a sessao de incontrolabilidade, como impeditivo da verificacao do efeito no teste (Grupo Ip). O papel das indicacoes na tela, os parametros utilizados e a presenca de contiguidades sistematicas foram discutidos / The results of learned helplessness studies with humans have been inconsistent. This is probably due to the systematic contiguity between the end of the aversive stimulus and the immediately preceding response during the uncontrollability session, which mimics an accidental control condition. Three experiments were conducted to establish a procedure with adequate experimental control to analyze the effects of an uncontrollability history upon learning of a new operant response in humans, as well as the prevention (immunization) of this effect. The first experiment demonstrated operant control under three negative reinforcement contingencies (variable sequences, maze, and discrimination of geometric forms), which allowed verifying the effect of the absence of control upon learning of a new operant response (Experiment 2 learned helplessness) and the effect of the absence of control, after a history of controllability, upon learning of a new operant response (Experiment 3 immunization). During the uncontrollability session, a number of variables were manipulated to avoid the accidental selection of the response being measured (duration of the stimulus, number of trials, response cost, and initial instructions). In Experiment 2, two groups were exposed to aversive tones (groups C and U) and one group was not (group N). For group C, the interruption of a high-pitch tone was contingent on the emission of variable sequences; for group U, the duration of the tone was response independent. Group U was further divided into two subgroups, according to the presence or absence of a hint on the screen (Up and U). After this manipulation, all participants had to solve a maze that was presented along with a tone. In Experiment 3, a pre-control group (P) was added to the ones in Experiment 2. The escape contingency for discriminating geometric forms was presented in the pre-treatment phase along with a tone. The results of the test phase indicated shorter latencies and a greater number of responses for groups C, N, and P, in comparison to the uncontrollable groups. For the latter groups, there was a negative correlation between the frequency of contiguities in the treatment phase and performance during the test phase. There was a low frequency of contiguities during treatment, and longer latencies and more errors during the test for Group U; an intermediate pattern was observed for Group Up. These results replicate the learned helplessness and immunization effects in humans, and suggest that this procedure is adequate to study these phenomena. The results also indicate that accidental selection during the uncontrollability session may eliminate the learned helplessness effect during the test (Group Up). The effects of the hints on the screen, the schedule parameters, and the presence of systematic contiguities are further discussed

<p><font face="Times New Roman"> <p align="left">This study looks at the effect of a cross-cultural instructional approach on the learners&rsquo / conceptions of lightning and attitude towards science. It explored Basotho conceptions of lightning and thunder under the following themes: nature of lightning, protection against lightning, animalistic/humanistic behaviour of lighting and nature of wounds inflicted by lightning.</p> </font></p>

The microstructure-property relationship for interpenetrating phase composites (IPCs) is currently poorly understood. In an attempt to improve this understanding this study focused on one particular part of this relationship: the effect of phase shape on the elastic and plastic behaviour. A review of previous research showed that investigations had linked phase shape to the elastic and plastic behaviour of various inclusion reinforced composites, but that no similar work had been completed for IPCs. <p> To study the complex response of the IPC microstructure under load, a numerical modelling analysis using the finite element method (FEM) was undertaken. Two three-dimensional models of IPCs were created, the first consisting of an interconnected spherical phase with the interstitial space forming the other interconnected phase, and the second replacing the spherical phase with an interconnected cylindrical phase. With the simulation of a uniaxial tension test under elastic and plastic conditions, these two models exhibited different responses based on the shape of the phases. <p> Results from an analysis of the macroscopic behaviour identified that the cylindrical model produced greater effective properties than the spherical model at the same volume fraction. The influence of phase shape was connected to the increased contiguity of the superior phase within the IPC for the cylindrical model, which allowed similar levels of long-range continuity with smaller amounts of the superior phase (compared to the spherical model). <p> An examination of microstructural stress distributions showed that preferential stress transfer occurred along paths of low compliance. This provided an explanation of how the improved contiguity of the stiffer (or stronger) phase could enhance the macroscopic effective properties of an IPC. Contiguity of the stronger phase was particularly important for plastic behaviour, where early yielding of the weaker phase requires the stronger phase to carry nearly all the load within itself.