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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Investigating the Relationship Between Objective and Subjective Measures of Physical Demand During Passive Exoskeleton Use

Kelley, Sydney Aelish 24 October 2023 (has links)
Passive exoskeletons hold promise in reducing the risk of work-related musculoskeletal disorders, however further research is essential before widespread adoption can occur. This study explores the feasibility of using subjective measures of physical demand in place of costly and less practical objective measures. Normalized electromyography (nEMG) data and ratings of perceived exertion (RPE) were collected from seven different studies conducted by the Occupational Ergonomics and Biomechanics Lab (OEB lab). Employing a repeated measures three-way ANOVA, we assessed the influence of nEMG, gender, and exoskeleton type on RPE. Additionally, mean nEMG and RPE from seven passive exoskeleton-based studies conducted outside the OEB lab were assessed in order to determine if the findings from the OEB lab existed across other research environments. The results demonstrated a general positive linear trend between nEMG and RPE for both the individual and mean results. Substantial inconsistencies emerged when considering the influence of gender, exoskeleton type, and task conditions on the relationship between nEMG and RPE. These discrepancies underscore the need for more in-depth research into this topic, specifically investigating the effects of gender and exoskeleton design. / Master of Science / Passive exoskeletons, devices designed to improve safety and provide support to the body, offer the potential for reducing muscle strain and reducing work-related injury risk. However, before these devices can be widely adopted, more research is necessary. Subjective measures of exertion, an affordable and user-friendly alternative to objective measures, require further investigation before replacing traditional methods in exoskeleton research. This study explores the possible connection between subjective and objective assessments of physical demand during passive exoskeleton usage. We analyzed data from seven studies conducted by the Occupational Ergonomics and Biomechanics Lab (OEB lab), focusing on muscle activity (an objective measure) and perceived exertion (a subjective measure). Our analysis examined the relationship between these objective and subjective measures, as well as how gender, exoskeleton type, and task conditions influenced this relationship. Additionally, we considered mean values from seven passive exoskeleton studies conducted outside the OEB lab, to investigate whether our findings existed in other research environments. The results revealed that as muscle activity increased, perceived exertion tended to increase as well. Moreover, our findings demonstrated that gender, exoskeleton type, and task conditions did influence the relationship, although there was significant variability in how these factors affected it. This research sheds light on the potential for using subjective measures in exoskeleton studies, bringing us closer to making exoskeletons more practical and accessible for real-world applications while acknowledging the complexities of this relationship.
2

Global Assessment of Attention Deficit Hyperactivity Disorder : Examining Objective Measures of Hyperactivity, Impulsivity and Inattention in Adults / Global Bedöming av Aktivitets- och Uppmärksamhetsstörning : Objektiva Mätningar av Hyperaktivitet, Impulsivitet och Ouppmärksamhet hos Vuxna Personer

Edebol, Hanna January 2012 (has links)
The aim of this thesis is to examine objective laboratory measures of Attention Deficit Hyperactivity Disorder (ADHD) in adult persons and to develop measures for diagnosis and treatment using a psychometric instrument called the Quantified Behavior Test Plus. The instrument objectively quantifies cardinal symptom manifestations in adult ADHD using motion tracking devices and continuous performance testing. Paper I-IV suggest that ADHD predisposes adult persons to perform poorer on continuous performance tasks and to have higher levels of motor activity while performing these tasks as compared to other clinical as well as non-clinical groups. Performance by adults with ADHD is normalized following stimulant treatment which implicates therapeutic effects and measures of response to treatment and remission for ADHD is suggested. Paper I concludes that the psychometric instrument needs to be calibrated with regard to adult ADHD and emphasizes the importance of a composite measure for the disorder. Paper II generates two new measures, the Weighed Core Symptom scale (WCS) - a composite measure of adult ADHD ranging from 0 to 100, and Prediction of ADHD (PADHD) - a categorical variable of the diagnostic status with good predictive power. A majority of participants with ADHD has low points on WCS (indicating high levels of symptoms) and a majority of non-ADHD normative participants has high points on WCS (indicating low levels of symptoms). Paper III examines WCS and PADHD among complex clinical groups with shared symptoms vis-à-vis ADHD. Here, findings from Paper II are replicated since participants with ADHD present the highest level of global symptoms, followed by participants with bipolar II disorder and borderline personality disorder, participant with diconfirmed ADHD and finally, non-clinical participants has the lowest level of global symptoms. In Paper IV, the measures are proposed as indications of response to treatment and remission after titration with stimulant treatment and WCS indicates response to small changes in dose level. The major findings of the present thesis may be summarized as the construction of two new objective measures for ADHD in adult persons with practical implications for diagnosis and treatment. Hyperactivity is the most specific marker of ADHD in both men and women, followed by the cognitive markers of inattention and impulsivity. The composite measure, WCS, quantifies the global amount of ADHD symptoms and provides the most sensitive measure for the disorder. PADHD and WCS may not replace a thorough neuropsychiatric assessment and further studies promoting diagnostic subtype stratification is suggested. Future studies may want to consider these measures in outcome-based investigations of treatment efficacy as well as in the study of neuropsychological endophenotypes. Practical implications include clinical strategies to enhance objectivity during assessment as well as optimizing beneficial effects of treatment and attaining remission.
3

Maternal Phenotype, Directly Measured Physical Activity and Associations with Placenta Nutrient Transport Related Gene Expression

Brett, Kendra Elizabeth January 2015 (has links)
The intrauterine environment plays an important role in fetal development and downstream health. Given the rise in maternal obesity and the incidence of babies being born large-for-gestational-age, research is needed exploring the mechanisms through which maternal obesity and health behaviours affect the delivery of nutrients to the fetus. This thesis includes three manuscripts in the pursuit of two objectives: 1) To determine whether there are changes in placenta nutrient transport-related gene expression in response to obesity, excess gestational weight gain, and variations physical activity and diet, and 2) To examine whether the Pregnancy Physical Activity Questionnaire is a reliable estimate of physical activity during the second trimester of pregnancy. In manuscript 1, we found that maternal obesity was not related to placenta nutrient transport-related gene expression, with the exception of lower placental mTOR expression in obese women who delivered male offspring, however, gestational weight gain was related to the gene expression of key proteins in the placenta. In manuscript 2, it was determined that the Pregnancy Physical Activity Questionnaire significantly overestimates physical activity and is not correlated with direct measures of activity and thus should not be used in future research. In manuscript 3, we found that physical activity and diet modify the expression of the genes involved in placenta nutrient transport. Meeting physical activity guidelines was associated with lower expression of a fatty acid transporter and higher expression of an amino acid transporter, while sugar intake was related to the expression of a glucose transporter. Together, the studies that make up this thesis suggest that there are numerous factors that may be contributing to placenta nutrient transport-related gene expression in humans and that future research on the placenta ought to include direct measures of physical activity and maternal diet, as well as account for gestational weight gain with respect to the guidelines and fetal sex.
4

Auditory models for evaluating algorithms

Kressner, Abigail A. 05 July 2011 (has links)
Hearing aids are tasked with the undesirable job of compensating an impaired, highly-nonlinear auditory system. Historically, these devices have either employed linear processing or relatively unsophisticated, nonlinear processing techniques. With increasingly more accurate models of the auditory system, expanding computational power, and many more objective measures which utilize these models, we are at a turning point in hearing aid design. Although subjective listener tests are often the most accepted methods for evaluating the quality and intelligibility of speech, they inherently treat the auditory system as a "black box." Conversely, model-based objective measures typically treat the auditory system as a cascade of physical processes. As a result, objective measures have the potential to provide more detailed information about how sound is processed and about where and why quality or intelligibility breaks down. Provided that we can generalize model-based objective measures, we can use the measures as tools for understanding how to best process degraded signals, and therefore, how to best design hearing aids. However, generalizability is a key requirement. Since many of the well-known objective measures have been developed for normal-hearing listeners in the context of audio codecs, we are unsure about the generalizability of these measures to predicting quality and intelligibility for hearing-impaired listeners with "unknown" datasets (i.e. a set on which it was not trained) and distortions which are specific to hearing aids. Relatively recently, however, Kates and Arehart (Journal of the Audio Engineering Society, 2010) proposed the Hearing Aid Speech Quality Index (HASQI), which is a model-based objective measure that predicts quality for normal-hearing and hearing-impaired listeners by taking into account many of the distortions which hearing aids introduce. HASQI solves many of our concerns of generalizability for predicting quality, but it still remains to test HASQI's ability to predict quality with datasets on which it was not trained. Thus, we explore the robustness of HASQI by testing its ability to predict quality for "unknown" de-noised speech, and we directly compare its performance to some other metrics in the literature.
5

Die Messung von Lernerfolg: / Eine grundsätzliche Aufgabe der Evaluation von Lehr- bzw. Trainingsinterventionen

Clasen, Heidi 15 February 2010 (has links) (PDF)
Im Bildungs- und Trainingsbereich erfolgen immer häufiger Evaluationen von Trainings, Workshops usw. Der Messung des Lernerfolgs der Interventionsteilnehmer kommt dabei im Rahmen von Mehr-Ebenen-Konzepten eine wichtige Rolle zu. Diese Evaluationen sind jedoch von formal-methodischen Problemen flankiert, wie dem Kriteriendilemma (Müller, 1987), das die Ambivalenz zwischen der Exaktheit von Datenerhebungen und deren Repräsentativität bezüglich der Programminhalte thematisiert. Des Weiteren ist Wissen domainenspezifisch und muss oft aktualisiert werden. Zuweilen fehlt eine vollständige Wissensbasis zur Konstruktion von Messinstrumenten. In diesem Fall wird häufig auf Selbsteinschätzungen zurückgegriffen. Diese praktikablen subjektiven Einschätzungen sind einerseits etablierte Messzugänge, z.B. in der Selbstkonzeptforschung (z.B. Moschner & Dickhäuser, 2006; Stiensmeier-Pelster & Schöne, 2008). Andererseits werden ihnen verschiedene Verzerrungstendenzen zugeschrieben (z.B. Mummendey & Grau, 2008). Metaanalytische Befunde (z.B. Moser, 1999) geben mittlere Zusammenhänge zwischen Selbsteinschätzungen und objektiven Leistungskriterien an und explizieren Kriterien für eine hohe Validität von Selbsteinschätzungen. Dabei stellt die Erwartung der Validierung der Selbsteinschätzungen das wichtigste Validitätskriterium dar. Alternativ zu subjektiven Messzugängen können so genannte objektive Messzugänge zur Erhebung des Lernerfolgs eingesetzt werden. Darunter versteht man u.a. Wissenstests mit offenem oder geschlossenem Antwortformat, die jedoch einen deutlichen höheren Konstruktions- bzw. Auswertungsaufwand erfordern. In der vorliegenden Arbeit sollen nun zwei methodologische Aspekte im Rahmen der Lernerfolgsmessung untersucht werden: die Differenzierungsfähigkeit und die Änderungssensitivität von Items, Subskalen und Skalen. Dabei sollen diese zwischen verschiedenen subjektiven und objektiven Messzugängen verglichen werden. Unter der Differenzierungsfähigkeit wird die Streuung der Items bzw. je Item verstanden (Lienert & Raatz, 1998). Muellerbuchhof & Zehrt (2004) nutzen für den Vergleich zwischen den Messzugängen den Experten-Novizen-Vergleich, wobei sich im objektiven Kompetenzmaß eine höhere Differenzierung zwischen den bekannten Gruppen zeigt als in den Selbsteinschätzungen. Die Änderungssensitivität gibt die Fähigkeit z.B. eines Items an, reale Veränderungen der jeweiligen Variablen widerzuspiegeln (Krauth, 1995). Für verschiedene Fremd- und Selbsteinschätzungsskalen und -items finden sich Hinweise auf die Änderungssensitivität derselben (z.B. Burlingame et al., 2006; Vermeersch et al., 2004). Es fehlen jedoch vergleichende Studien zu objektiven Messzugängen. In der vorliegenden Arbeit wird nun zuerst geprüft, ob sich subjektive und objektive Messzugänge hinsichtlich ihrer Differenzierungsfähigkeit und ihrer Änderungssensitivität unterscheiden. Weiterhin soll bestimmt werden, welcher Messzugang in welchem Ausmaß besser differenziert und interventionsbedingte Veränderungen sensitiver abbildet. Des Weiteren soll nach der Art des erhobenen Wissens (Faktenwissen oder Anwendungswissen) unterschieden werden. Anschließend sollen verschiedene objektive Messzugänge entsprechend verglichen werden. Zuletzt erfolgt ein Vergleich von zwei Arten von Selbsteinschätzungen. Im Ergebnis sollen jeweils praktikable Empfehlungen für den Einsatz in Evaluationsvorhaben abgeleitet werden. Die globalen Fragestellungen zur Differenzierungsfähigkeit werden anhand von zwei Studien an Studierenden geprüft: in einer methodologischen Analyse einer quasiexperimentellen Trainingsevaluationsstudie (Clasen, 2007; Winkelmann, 2009) (Studie1) sowie in einer experimentellen Studie einer Kursevaluation (Studie 2). In Studie 1 werden dabei der Bestimmung der Differenzierungsfähigkeit Veränderungswerte und in Studie 2 Statuswerte zugrunde gelegt. Die Fragestellungen zur Änderungssensitivität sowie zur Differenzierungsfähigkeit der subjektiven und objektiven Messzugänge untereinander werden anhand von Studie 2 bearbeitet. Im Ergebnis zeigt sich, dass der objektiv offene Messzugang am besten in der Lage ist, zwischen Personen zu differenzieren und treatmentbedingte Veränderungen abzubilden. Dieser ist jedoch auch am aufwändigsten in der Durchführung und besonders in der Auswertung, welche inhaltliche Fachkompetenz des Auswertenden voraussetzt. Die praktikablen Selbsteinschätzungen (einzelne Einschätzungen, die aggregiert werden, sowie Globaleinschätzungen) der Studierenden nehmen den zweiten Platz ein, dicht gefolgt vom objektiv geschlossenen Messzugang, der z.T. auch bessere Ergebnisse liefert als die Selbsteinschätzungen. Sobald in einer Evaluationsstudie jedoch Zweifel an der Validität der Selbsteinschätzungen gerechtfertigt sind, ist ein objektiver Messzugang zu bevorzugen. Innerhalb des objektiv geschlossenen Messzugangs verfügt die weniger übliche Darstellung als Block von „stimmt- stimmt nicht“- Antworten über eine bessere Differenzierungsfähigkeit und Änderungssensitivität als das Multiple Choice- Format. Des Weiteren differenziert die Subskala Anwendungswissen für jeden untersuchten Messzugang tendenziell besser als die Subskala Faktenwissen. Diese Ergebnisse werden in den Forschungskontext eingeordnet, Kritikpunkte der Studien werden thematisiert. Für den Evaluator werden aus den Ergebnissen der vorliegenden Arbeit jeweils praktikable Empfehlungen zum Einsatz der verschiedenen Messzugänge in Evaluationsvorhaben abgeleitet.
6

THE ASSOCIATIONS AMONG ETHNICITY, CONTEXTUAL FACTORS, AND DIETARY INTAKE IN THE CANADIAN ALLIANCE FOR HEALTHY HEARTS AND MINDS: A CROSS-SECTIONAL STUDY.

Randolph-Koranteng, Nina Naa Awura January 2023 (has links)
Introduction: Unhealthy diets are significant contributors to chronic diseases. Variations in CVD rates across ethnicities in Canada could be attributable to diverse dietary habits and nutrition environmental influences. The extent to which individuals’ food environment perceptions influence dietary intake is also understudied. Methods: This cross-sectional study, utilizing data from 7,077 of the 10,100 adults in the Canadian Alliance for Healthy Hearts and Minds (CAHHM) cohort, assessed associations of elements of the nutrition environment (food prices, advertisements, and availability) and ethnicity with dietary intakes. Results: Self-reported intakes of carbohydrates, junk foods, meat, and cholesterol varied significantly across Asians and White Europeans (p<0.0001). Rural/urban differences were also observed in carbohydrate, fat, protein, cholesterol, vegetable, meat, and sweet drink intakes (p<0.0001), excluding junk foods, and fruits. Interestingly, while individuals' perceptions of their food environment did not correlate with objective measures of the same environment, a 1$ increase in vegetable prices was significantly associated with a decrease in vegetable consumption by 0.0078 In(servings/day) (p= 0.0233), after adjusting for rural/urban living, ethnicity and BMI. No associations were found between fruits, meat, bread, eggs, cola, chocolate, poultry, rice, and milk prices and respective intakes. No association was also found between fruit/vegetable availability and consumption; nor between junk foods, sweet drinks and fruit/vegetable ads and consumption. Notably, alcohol advertisement was associated with alcohol intake. Discussion/Conclusion: The price-inelastic nature of foods like milk and eggs due to their perceived essentiality, implies the superimposing effects of other factors on consumption aside, price. While food advertisements undoubtedly impact eating behaviours, their influence might be subtle considering factors like price which could pose barriers to healthy eating. These findings emphasize the intricate interplay between prices, availability, advertisement, and other factors and dietary choices. Policymakers, food industries, and health advocates can leverage these insights to create healthier food environments for improved health. / Thesis / Master of Science (MSc) / Unhealthy diets are significant contributors to chronic diseases. Diverse influences from the nutrition environment also impact consumption. To better inform public health strategies promoting healthy eating, it is imperative to ascertain whether modifying the food environment of individuals would be more effective in transforming their eating behaviours. This cross-sectional study, utilizing data from 7,077 adults from the CAHHM cohort, assessed the influence of elements of the nutrition environment and ethnicity on dietary intake. Differences in carbohydrate, junk food, meat, and cholesterol intake were found among Asians and White Europeans. Carbohydrate, fat, protein, vegetable, meat, and sweet drink intakes varied between rural and urban settings. Increased vegetable prices were associated with reduced consumption, while food advertisements were not associated with dietary intake. This study shows that the costs of healthy foods impact dietary choices more than advertisements. Policymakers can utilize these findings to promote healthy food environments in Canada.
7

Uma metodologia para exploração de regras de associação generalizadas integrando técnicas de visualização de informação com medidas de avaliação do conhecimento / A methodology for exploration of generalized association rules integrating information visualization techniques with knowledge evaluation measures

Fujimoto, Magaly Lika 04 August 2008 (has links)
O processo de mineração de dados tem como objetivo encontrar o conhecimento implícito em um conjunto de dados para auxiliar a tomada de decisão. Do ponto de vista do usuário, vários problemas podem ser encontrados durante a etapa de pós-processamento e disponibilização do conhecimento extraído, como a enorme quantidade de padrões gerados por alguns algoritmos de extração e a dificuldade na compreensão dos modelos extraídos dos dados. Além do problema da quantidade de regras, os algoritmos tradicionais de regras de associação podem levar à descoberta de conhecimento muito específico. Assim, pode ser realizada a generalização das regras de associação com o intuito de obter um conhecimento mais geral. Neste projeto é proposta uma metodologia interativa que auxilie na avaliação de regras de associação generalizadas, visando melhorar a compreensibilidade e facilitar a identificação de conhecimento interessante. Este auxílio é realizado por meio do uso de técnicas de visualização em conjunto com a aplicação medidas de avaliação objetivas e subjetivas, que estão implementadas no módulo de visualização de regras de associação generalizados denominado RulEE-GARVis, que está integrado ao ambiente de exploração de regras RulEE (Rule Exploration Environment). O ambiente RulEE está sendo desenvolvido no LABIC-ICMC-USP e auxilia a etapa de pós-processamento e disponibilização de conhecimento. Neste contexto, também foi objetivo deste projeto de pesquisa desenvolver o Módulo de Gerenciamento do ambiente de exploração de regras RulEE. Com a realização do estudo dirigido, foi possível verificar que a metodologia proposta realmente facilita a compreensão e a identificação de regras de associação generalizadas interessantes / The data mining process aims at finding implicit knowledge in a data set to aid in a decision-making process. From the users point of view, several problems can be found at the stage of post-processing and provision of the extracted knowledge, such as the huge number of patterns generated by some of the extraction algorithms and the difficulty in understanding the types of the extracted data. Besides the problem of the number of rules, the traditional algorithms of association rules may lead to the discovery of very specific knowledge. Thus, the generalization of association rules can be realized to obtain a more general knowledge. In this project an interactive methodology is proposed to aid in the evaluation of generalized association rules in order to improve the understanding and to facilitate the identification of interesting knowledge. This aid is accomplished through the use of visualization techniques along with the application of objective and subjective evaluation measures, which are implemented in the visualization module of generalized association rules called RulEE-GARVis, which is integrated with the Rule Exploration Environment RulEE. The RulEE environment is being developed at LABIC-ICMC-USP and aids in the post-processing and provision of knowledge. In this context, it was also the objective of this research project to develop the Module Management of the rule exploration environment RulEE. Through this directed study, it was verified that the proposed methodology really facilitates the understanding and identification of interesting generalized association rules
8

Uma metodologia para exploração de regras de associação generalizadas integrando técnicas de visualização de informação com medidas de avaliação do conhecimento / A methodology for exploration of generalized association rules integrating information visualization techniques with knowledge evaluation measures

Magaly Lika Fujimoto 04 August 2008 (has links)
O processo de mineração de dados tem como objetivo encontrar o conhecimento implícito em um conjunto de dados para auxiliar a tomada de decisão. Do ponto de vista do usuário, vários problemas podem ser encontrados durante a etapa de pós-processamento e disponibilização do conhecimento extraído, como a enorme quantidade de padrões gerados por alguns algoritmos de extração e a dificuldade na compreensão dos modelos extraídos dos dados. Além do problema da quantidade de regras, os algoritmos tradicionais de regras de associação podem levar à descoberta de conhecimento muito específico. Assim, pode ser realizada a generalização das regras de associação com o intuito de obter um conhecimento mais geral. Neste projeto é proposta uma metodologia interativa que auxilie na avaliação de regras de associação generalizadas, visando melhorar a compreensibilidade e facilitar a identificação de conhecimento interessante. Este auxílio é realizado por meio do uso de técnicas de visualização em conjunto com a aplicação medidas de avaliação objetivas e subjetivas, que estão implementadas no módulo de visualização de regras de associação generalizados denominado RulEE-GARVis, que está integrado ao ambiente de exploração de regras RulEE (Rule Exploration Environment). O ambiente RulEE está sendo desenvolvido no LABIC-ICMC-USP e auxilia a etapa de pós-processamento e disponibilização de conhecimento. Neste contexto, também foi objetivo deste projeto de pesquisa desenvolver o Módulo de Gerenciamento do ambiente de exploração de regras RulEE. Com a realização do estudo dirigido, foi possível verificar que a metodologia proposta realmente facilita a compreensão e a identificação de regras de associação generalizadas interessantes / The data mining process aims at finding implicit knowledge in a data set to aid in a decision-making process. From the users point of view, several problems can be found at the stage of post-processing and provision of the extracted knowledge, such as the huge number of patterns generated by some of the extraction algorithms and the difficulty in understanding the types of the extracted data. Besides the problem of the number of rules, the traditional algorithms of association rules may lead to the discovery of very specific knowledge. Thus, the generalization of association rules can be realized to obtain a more general knowledge. In this project an interactive methodology is proposed to aid in the evaluation of generalized association rules in order to improve the understanding and to facilitate the identification of interesting knowledge. This aid is accomplished through the use of visualization techniques along with the application of objective and subjective evaluation measures, which are implemented in the visualization module of generalized association rules called RulEE-GARVis, which is integrated with the Rule Exploration Environment RulEE. The RulEE environment is being developed at LABIC-ICMC-USP and aids in the post-processing and provision of knowledge. In this context, it was also the objective of this research project to develop the Module Management of the rule exploration environment RulEE. Through this directed study, it was verified that the proposed methodology really facilitates the understanding and identification of interesting generalized association rules
9

Objective Measure of Two Musical Interpretations of an Excerpt from Berlioz's "La Mort d'Ophelie"

Lau, Hiu Yan Crystal 18 June 2020 (has links)
No description available.
10

Die Messung von Lernerfolg:: Eine grundsätzliche Aufgabe der Evaluation von Lehr- bzw. Trainingsinterventionen

Clasen, Heidi 20 January 2010 (has links)
Im Bildungs- und Trainingsbereich erfolgen immer häufiger Evaluationen von Trainings, Workshops usw. Der Messung des Lernerfolgs der Interventionsteilnehmer kommt dabei im Rahmen von Mehr-Ebenen-Konzepten eine wichtige Rolle zu. Diese Evaluationen sind jedoch von formal-methodischen Problemen flankiert, wie dem Kriteriendilemma (Müller, 1987), das die Ambivalenz zwischen der Exaktheit von Datenerhebungen und deren Repräsentativität bezüglich der Programminhalte thematisiert. Des Weiteren ist Wissen domainenspezifisch und muss oft aktualisiert werden. Zuweilen fehlt eine vollständige Wissensbasis zur Konstruktion von Messinstrumenten. In diesem Fall wird häufig auf Selbsteinschätzungen zurückgegriffen. Diese praktikablen subjektiven Einschätzungen sind einerseits etablierte Messzugänge, z.B. in der Selbstkonzeptforschung (z.B. Moschner &amp; Dickhäuser, 2006; Stiensmeier-Pelster &amp; Schöne, 2008). Andererseits werden ihnen verschiedene Verzerrungstendenzen zugeschrieben (z.B. Mummendey &amp; Grau, 2008). Metaanalytische Befunde (z.B. Moser, 1999) geben mittlere Zusammenhänge zwischen Selbsteinschätzungen und objektiven Leistungskriterien an und explizieren Kriterien für eine hohe Validität von Selbsteinschätzungen. Dabei stellt die Erwartung der Validierung der Selbsteinschätzungen das wichtigste Validitätskriterium dar. Alternativ zu subjektiven Messzugängen können so genannte objektive Messzugänge zur Erhebung des Lernerfolgs eingesetzt werden. Darunter versteht man u.a. Wissenstests mit offenem oder geschlossenem Antwortformat, die jedoch einen deutlichen höheren Konstruktions- bzw. Auswertungsaufwand erfordern. In der vorliegenden Arbeit sollen nun zwei methodologische Aspekte im Rahmen der Lernerfolgsmessung untersucht werden: die Differenzierungsfähigkeit und die Änderungssensitivität von Items, Subskalen und Skalen. Dabei sollen diese zwischen verschiedenen subjektiven und objektiven Messzugängen verglichen werden. Unter der Differenzierungsfähigkeit wird die Streuung der Items bzw. je Item verstanden (Lienert &amp; Raatz, 1998). Muellerbuchhof &amp; Zehrt (2004) nutzen für den Vergleich zwischen den Messzugängen den Experten-Novizen-Vergleich, wobei sich im objektiven Kompetenzmaß eine höhere Differenzierung zwischen den bekannten Gruppen zeigt als in den Selbsteinschätzungen. Die Änderungssensitivität gibt die Fähigkeit z.B. eines Items an, reale Veränderungen der jeweiligen Variablen widerzuspiegeln (Krauth, 1995). Für verschiedene Fremd- und Selbsteinschätzungsskalen und -items finden sich Hinweise auf die Änderungssensitivität derselben (z.B. Burlingame et al., 2006; Vermeersch et al., 2004). Es fehlen jedoch vergleichende Studien zu objektiven Messzugängen. In der vorliegenden Arbeit wird nun zuerst geprüft, ob sich subjektive und objektive Messzugänge hinsichtlich ihrer Differenzierungsfähigkeit und ihrer Änderungssensitivität unterscheiden. Weiterhin soll bestimmt werden, welcher Messzugang in welchem Ausmaß besser differenziert und interventionsbedingte Veränderungen sensitiver abbildet. Des Weiteren soll nach der Art des erhobenen Wissens (Faktenwissen oder Anwendungswissen) unterschieden werden. Anschließend sollen verschiedene objektive Messzugänge entsprechend verglichen werden. Zuletzt erfolgt ein Vergleich von zwei Arten von Selbsteinschätzungen. Im Ergebnis sollen jeweils praktikable Empfehlungen für den Einsatz in Evaluationsvorhaben abgeleitet werden. Die globalen Fragestellungen zur Differenzierungsfähigkeit werden anhand von zwei Studien an Studierenden geprüft: in einer methodologischen Analyse einer quasiexperimentellen Trainingsevaluationsstudie (Clasen, 2007; Winkelmann, 2009) (Studie1) sowie in einer experimentellen Studie einer Kursevaluation (Studie 2). In Studie 1 werden dabei der Bestimmung der Differenzierungsfähigkeit Veränderungswerte und in Studie 2 Statuswerte zugrunde gelegt. Die Fragestellungen zur Änderungssensitivität sowie zur Differenzierungsfähigkeit der subjektiven und objektiven Messzugänge untereinander werden anhand von Studie 2 bearbeitet. Im Ergebnis zeigt sich, dass der objektiv offene Messzugang am besten in der Lage ist, zwischen Personen zu differenzieren und treatmentbedingte Veränderungen abzubilden. Dieser ist jedoch auch am aufwändigsten in der Durchführung und besonders in der Auswertung, welche inhaltliche Fachkompetenz des Auswertenden voraussetzt. Die praktikablen Selbsteinschätzungen (einzelne Einschätzungen, die aggregiert werden, sowie Globaleinschätzungen) der Studierenden nehmen den zweiten Platz ein, dicht gefolgt vom objektiv geschlossenen Messzugang, der z.T. auch bessere Ergebnisse liefert als die Selbsteinschätzungen. Sobald in einer Evaluationsstudie jedoch Zweifel an der Validität der Selbsteinschätzungen gerechtfertigt sind, ist ein objektiver Messzugang zu bevorzugen. Innerhalb des objektiv geschlossenen Messzugangs verfügt die weniger übliche Darstellung als Block von „stimmt- stimmt nicht“- Antworten über eine bessere Differenzierungsfähigkeit und Änderungssensitivität als das Multiple Choice- Format. Des Weiteren differenziert die Subskala Anwendungswissen für jeden untersuchten Messzugang tendenziell besser als die Subskala Faktenwissen. Diese Ergebnisse werden in den Forschungskontext eingeordnet, Kritikpunkte der Studien werden thematisiert. Für den Evaluator werden aus den Ergebnissen der vorliegenden Arbeit jeweils praktikable Empfehlungen zum Einsatz der verschiedenen Messzugänge in Evaluationsvorhaben abgeleitet.

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