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Vermittler - Bewahrer - Wächter. Orientierungen von Lehrerinnen und Lehrern im Themenfeld Kultur
(2020)
Auf Grundlage welchen Kulturbegriffs die Lehrkräfte innerhalb des Deutschunterrichts der Grundschule handeln, ist zentrales Thema der vorliegenden Arbeit. Mit Hilfe von Gruppendiskussionen fragt die Studie nach implizitem Wissen der Lehrer*innen im Themenfeld Kultur. Neben der Überwindung kulturellen Defizits kann mit Hilfe der dokumentarischen Methode ein Ethnozentrismus als pädagogische Leitidee rekonstruiert werden. Ein Ausweg daraus wird im bedeutungsorientierten Kulturbegriff als Grundlage eines kultursensiblen Deutschunterrichts aufgezeigt.
In den Kulturwissenschaften werden eine Vielzahl von Kulturbegriffen diskutiert, dies geschieht allerdings kaum für den schulischen Kontext. Der Kulturbegriff, der dem Denken und Handeln der Lehrer*innen zugrunde liegt, ist jedoch Grundlage für stattfindende ethnische Zuschreibungen oder Stigmatisierungen und gleichzeitig auch Basis für eine gelungene Gleichstellung aller Schüler*innen.
Das Forschungsprojekt stellt die Lehrkraft als zentralen Akteur innerhalb des Unterrichtsprozesses in den Mittelpunkt: Welches Verständnis von Kultur liegt ihrem Deutschunterricht in der Grundschule zugrunde? Die Studie fragt danach, welche Orientierungsrahmen, welche impliziten Wissensbestände im Themenfeld Kultur bei Lehrer*innen zu rekonstruieren sind, um so ein besseres Verständnis der kollektiven Wahrnehmung zu generieren.
In der praxeologischen Arbeit werden mit Hilfe des Gruppendiskussionsverfahrens und der dokumentarischen Methode konjunktive Erfahrungsräume der Lehrer*innen im Themenfeld Kultur rekonstruiert. Alle Gruppen, jeweils ganz unterschiedlich, verhandeln die Überwindung des kulturellen Defizits. Darauf aufbauend zeigt sich, dass die Lehrer*innen auf einen kollektiven Habitus kultureller Wissensvermittlung auf Basis eines ethnozentristischen Weltbildes zurückgreifen. Durch das kulturelle Nichtwissen bleibt den Lehrkräften ein pädagogisch-kultursensibler Handlungsspielraum verwehrt.
Mit Hilfe des bedeutungsorientierten Kulturbegriffs kann dieser Spielraum im Themenfeld Kultur geweitet werden, indem die individuelle und kulturelle Vielfalt aus der Perspektive der Schüler*innen thematisiert werden. Er bildet einen Baustein, um mit einer ganzheitlichen Kultur- und Diversitätsdidaktik das methodisch-didaktische Desiderat im Feld des Deutschunterrichts aufzuheben.
Order picking and delivery are integral parts of many supply chains, especially those of retail and online trade. They are mostly non-value-adding, downstream processes, but they are responsible for the majority of logistics costs. Accordingly, the academic literature deals with both order picking and vehicle routing in a diverse and detailed manner. However, a holistic view of both processes is mostly not sufficiently taken into account. The interdependent effects on the operational planning level are only considered to a limited extent since the processes are usually considered isolated or sequential planning is assumed. This thesis examines different order picking and vehicle routing problems. Furthermore, it shows the advantages of integrative planning and develops exact and heuristic solution methods for the investigated problems.
The first paper develops a structural understanding of the subproblems of picking and delivery. In addition, the article illustrates the development of the research branch of integrative order picking and vehicle routing.
Further contributions examine practice-oriented problems in the field of micro-store deliveries (contribution 2), same-day deliveries (contribution 3), and the supply of supermarkets (contribution 4). In each case, different real-world constraints are included and different objectives are addressed. Furthermore, problem-specific integrative solution methods are developed and compared to classical approaches.
Automation technologies and human capital are fundamental drivers of economic growth. The motivation of this thesis is to advance the literature by providing novel insights into the determinants of automation innovation and human capital. For this purpose, this thesis exploits immigration episodes, uses empirical methods for causal inference and introduces new sources of data on immigrants and automation innovation. Chapter 2 and Chapter 3 each examine the relationship between labor endowments and automation innovation. Chapter 4 examines the effects of ethnic concentration on immigrant childrens' acquisition of human capital.
In many countries today, a rising life expectancy and the associated demographic shift, coupled with the advancements of modern medicine, has fueled an ever-increasing cost pressure on healthcare systems. A driving factor for these rising costs can be seen in inpatient stays in hospitals that in many cases are connected to cost-intensive treatments. A central concern of any hospital management in such an environment is therefore to understand how to make the best possible use of available resources. A decisive factor in this regard is the management of bed capacities.
The present cumulative dissertation comprises four contributions, which address
open research questions in the field of strategic, tactical and operative bed planning:
1 Walther, M., 2020. Strategical, tactical, and operational aspects of bed
planning problems in hospital environments. Submission planned to
Social Science Research Network (SSRN)
2 Hübner, A., Kuhn, H., Walther, M., 2018. Combining clinical departments
and wards in maximum-care hospitals. OR Spectrum 40, 679-709
3 Schäfer, F., Walther, M., Hübner, A., Kuhn, H., 2019. Operational
patient-bed assignment problem in large hospital settings including overflow
and uncertainty management. Flexible Services and Manufacturing
Journal 31, 1012–1041
4 Schäfer, F., Walther, M., Hübner, A., Grimm, D., 2020. Machine learning
and pilot method: tackling uncertainty in the operational patient-bed
assignment problem. Submitted to OR Spectrum on 13 February 2020
The first contribution sets out to provide an overview over the different hierarchical planning levels on which bed planning problems may be addressed. It should be noted in this context that several different aspects may be combined under the collective term “bed planning”. These may be delimited in terms of their scope and their planning horizon. A frequently used taxonomy in this context is the hierarchical subdivision of typical problems in health care into strategical, tactical and operational levels as provided by Hulshof et al. (2012). In the context of bed planning, a typical strategical problem is how to combine departments and wards to obtain benefits from pooled ward capacity. On a tactical level, an exemplary problem setting related to bed planning can be seen in devising master surgery schedules that optimize downstream bed occupancy levels as patients returning from surgery will require a bed for post-surgical recovery and monitoring. Finally,
on an operational level, patient-bed allocations need to be optimized while taking the objectives and constraints of patients and medical staff alike into account.
To start, the second contribution deals with the strategical problem of combining departments into groups and assigning pooled ward capacity to these groups with the goal of balancing bed occupancy levels within a hospital. Specifically, one of the underlying goals is to minimize the amount of beds required to meet a predetermined service level. However, merging ward capacities with the aim of simultaneously accommodating patients from different medical departments increases the complexity of organizing and ensuring proper care for these patients. This leads to so-called pooling costs. To tackle this problem, a modeling and solution approach is developed which is based on a generalized partitioning problem and is solved by integer
linear programming (ILP). This enables hospital management to determine the cost-optimal combination of all departments and wards in a hospital, while ensuring that predetermined thresholds with regard to maximum
walking distances for doctors and patients are adhered to.
Once pooled ward capacities are established, the solution space for allocating incoming patients to beds is greatly increased and the underlying allocation problem quickly becomes too complex to be handled without computational support. In this regard the third contribution ties in with the second contribution in that it deals with optimizing the operational patient-bed allocation problem. In order to enable optimal allocation of patients to beds, it is important to identify and take into account the individual needs and
limitations of the three main stakeholders involved, namely patients, doctors, and nursing staff. All of these stakeholders exhibit different and sometimes contradicting objectives and constraints, such that a trade-off has to be made that maximizes the overall utility for the hospital. In addition, the complexity of the problem is increased by the high volatility and uncertainty regarding patient arrivals, types of illnesses, and the resulting remaining lengths of stay of newly arriving patients. In order to address this situation,
a mathematical model and solution approach for the patient-bed allocation problem is developed that is designed to generate solutions for large, real-life operative planning situations. In addition to being able to deal with overflow situations, this solution approach further takes different patient types into account, for example by anticipating emergency patient arrivals.
Finally, the fourth contribution builds on the third contribution in that the modeling and solution approach to allocate patients to beds is extended by several aspects. As mentioned above, hospitals have to deal with uncertainty regarding the actual demand for beds. Here, the fourth contribution improves the anticipation of emergency patients by using machine learning. Specifically, weather data, seasons, important local and regional events, and current and historical occupancy rates are combined to better anticipate emergency inpatient arrivals. In addition, a hyper-heuristic approach is developed based on the pilot method defined by Voß et al. (2005). By combining the improved anticipation of emergency patients with this hyperheuristic approach significant improvements can be achieved compared to the solution approach presented in the third contribution.
Recommending products that are helpful to customers and tailored to their needs is of pivotal importance for successful online retailing. Online purchase data is typically used to generate such recommendations. This dissertation studies two topic models that use purchase data to make product recommendations. The Author Topic Model (ATM) and Sticky Author Topic Model (Sticky ATM) are applied to the purchase data of an online retailer of animal health products, and their predictive performances are contrasted with those of the benchmark methods Unigram, Bigram, and Collaborative Filtering (CF). This work focuses on the generation of new product recommendations. To increase novelty in recommendations, a new pre-processing approach is presented. The data is prepared prior to model application such that more novel products are included in the recommendations. A total of six data preparation variants are tested. The key finding is that topic models are very competitive with the benchmark methods and outperform them with the data preparation variant, where repetitively purchased items (repeat items) and customers with one item transaction (single-item customers) are eliminated from the data. Marketing practitioners should consider this pre-processing when implementing topic models as recommender models in their online shops.
The cumulative dissertation "Optimization models for shelf space allocation in retail stores" consists of the four individual scientific contributions listed below:
1. Düsterhöft, Tobias, Hübner, Alexander and Schaal, Kai (2020): A practical approach to the shelf-space allocation and replenishment problem with heterogeneously sized shelves.
2. Hübner, Alexander, Düsterhöft, Tobias and Ostermeier, Manuel (2020): An optimization approach for product allocation with integrated shelf space dimensioning in retail stores.
3. Ostermeier, Manuel, Düsterhöft, Tobias and Hübner, Alexander (2020): A model for the store wide shelf space allocation.
4 Düsterhöft, Tobias (2020): Retail shelf space planning - Differences, problems and opportunities of applied optimization models.
The planning and best possible utilization of the available shelf space is of central importance for retailers. Shelf space is a scarce resource in stores today. Shelf planners need to determine optimal shelf spaces for each item within product allocation. Researchers have already developed several decision support models. Usually, these models have in common that they can make a decision on the number of facings per product. A facing is a visible sales unit of a product on the shelf. Behind a facing, depending on the depth of the shelf further sales units are located. With an increase in the number of facings the visibility of the product for customers is also increasing, which is associated with a certain demand effect, the so-called space elasticity.
The content of this dissertation are optimization models that extend existing approaches to product allocation significantly and thus also enable a practical application of these approaches. Within the framework of a practical project substantial new contents for the product allocation can be determined. The resulting optimization models build on each other. Initially, in the 1st article the product allocation is extended by an exact consideration of the shelf space dimensions. The resulting question of the optimal shelf layout is the central part of the 2nd article. If the layouts of shelves are determined on the shelf, the total shelf space per category must be known beforehand. This question is dealt with in the 3rd article. Finally, new research fields are identified in the 4th article based on current real processes and requirements.
In this cumulative dissertation, I investigate the relation between the cognitive complexity of work tasks and economic outcomes such as earnings, migration, and aggregate income growth. Existing theoretical and empirical research firmly established that human capital plays a major role in determining these outcomes. However, the literature to date has focused on a limited set of human capital measures, such as education, years of work experience, and basic demographic characteristics, and has largely ignored considerable individual variation attributable to occupational skills. By introducing novel skill measures derived from work tasks and using theoretical models combined with empirical evidence, I demonstrate the determining role played by occupational skills.
The first paper examines the connection between problem solving and lifecycle wage dynamics. I introduce a model of learning-by-doing which relates the intensity of complex tasks to the growth of problem solving skills and labour productivity. Using German administrative data, I find that workers in complex jobs receive static and dynamic wage premia and acquire relatively more human capital throughout life.
The second paper examines the selection pattern of Mexican migrants to the United States and shows that Mexican migrants have lower cognitive skills and higher manual skills compared to non-migrants. Using an extended version of the Roy-Borjas model, I show that differences in the returns to occupational skills explain the selection pattern better than differences in the returns to education and basic characteristics.
The third paper explores the role that complexity plays in economic development. I develop a regional model of endogenous growth which relates aggregate problem solving skills to the rate of technology adoption. In the model, migration costs and spillovers in technology adoption create persistent differences in regional income. By estimating growth regressions, I find that problem solving skills strongly predict per capita income growth in a sample of European regions.
The results collected in the dissertation have implications for economic development policies focused on human capital, projection and analysis of international migration, and evaluating long-term effects of recessions.
Diese Studie untersucht am Beispiel des Arava Institute for Environmental Studies in Israel, wie umweltbasierte Friedensbildungsmaßnahmen die Wahrnehmung eines Konflikts bei Akteuren auf der Graswurzelebene verändern können. Ausgangsüberlegung ist dabei, Umwelt nicht nur als Teil des Konfliktes zu interpretieren, sondern als konfliktneutralen Katalysator einzusetzen. Die auf dieser Basis erreichte Veränderung der Wahrnehmung des Konflikts wird in Form von konstruierten Raumbildern sowie den Bausteinen der Versöhnung nach LEDERACH (1997) konzeptualisiert. Die empirischen Einblicke zeigen zum einen die Bedeutung von physischen wie sozialen Orten und Räumen als Rahmen für die konstruktive Auseinandersetzung. Zum anderen lässt sich in Bezug auf die Konfliktwahrnehmung ein Bruch zwischen einer positiven Veränderung des Bildes der anderen Gruppe sowie dem Wunsch nach Frieden und der persistenten Konstruktion des Erbes sowie dem schweren Schritt der Vergebung ableiten.
Die kumulative Dissertation befasst sich im Rahmen der holistischen Customer Experience (CX) zum einen mit unterbewussten Einflussfaktoren auf die CX und wie negative Effekte in diesem Zusammenhang gelindert werden können. Zum anderen wird die Customer Experience von einer Business-to-Business Perspektive analysiert. Insgesamt umfasst die Dissertation vier Beiträge:
Beitrag 1:
Stereotypes in Services – A Systematic Literature Review to Move from Scattered Insights to Generalizable Knowledge
Beitrag 2:
Overcoming Vulnerability: Channel Design Strategies to Alleviate Vulnerability Perceptions in Customer Journeys
Beitrag 3:
Are You Right for the Job? The Influence of Service Provider Stereotypes on Customer’s Willingness to Engage in Co-Production
Beitrag 4:
The Business-to-Business Customer Experience – An aggregated Company Experience Based on Multiple Department and Employee Journeys
Basierend auf der Annahme, dass die Customer Experience im Rahmen vieler Einflussfaktoren auch durch soziale Standards, Normen und Ideale beeinflusst werden kann, konzentriert sich der erste Artikel auf die Wirkung von Stereotypen in Dienstleistungsinteraktionen. Der Literaturüberblick identifiziert dabei zahlreiche Auswirkungen von Stereotypen, stellt dabei jedoch fest, dass Maßnahmen, um diese Auswirkungen zu mildern deutlich weniger untersucht wurden. Vor diesem Hintergrund untersucht der zweite Beitrag konzeptionell wie das Channel Management dazu beitragen kann, die CX von benachteiligten Kundengruppen zu verbessern. Der dritte Beitrag adressiert eine weitere Forschungslücke die in Beitrag 1 identifiziert wurde, nämlich fehlende Einblicke in den Prozess, wie soziale Beurteilungen zu negativen Kundenerlebnissen führen. Mittels zweier Studien zeigt der Beitrag, dass Kunden auf Grund von Stereotypen weniger bereit sind mit Mitarbeitern zu interagieren, was den Erfolg der Dienstleistungserbringung gefährdet. Der vierte Beitrag nimmt eine deutlich abweichende Perspektive im Rahmen der CX ein und untersucht die bisher wenig beachtete CX in einem gewerblichen Business-to-Business Kontext.
Die vorliegende Arbeit beinhaltet drei Studien mit der Methode des ambulanten Assessments, welche die Zielsetzung haben, einen Beitrag zur Überprüfung bzw. Weiterentwicklung aktueller arbeitspsychologischer Theorien zu leisten. Die erste Studie thematisiert die Frage nach möglichen Interaktionen zwischen Anforderungen. Mehrebenen-Analysen basierend auf einer Stichprobe von 97 Krankenpflegekräften und 1026 Situationsfragebögen ergaben signifikante Interaktionen von Arbeitsdruck und emotionalen Anforderungen für drei von fünf abhängigen Variablen (emotionale Erschöpfung, Vitalität und Hingabe). Der wichtigste Beitrag dieser Studie ist, die Existenz von Interaktionen zwischen verschiedenen Anforderungen aufzuzeigen. In der zweiten Studie wird untersucht, ob inkonsistente Mediation eine mögliche Erklärung für die inkonsistente Befundlage bzgl. des motivationalen Potenzials von Herausforderungs-Anforderungen darstellt. In Mehrebenen-Pfadmodellen (95 Altenpflegekräfte, 871 Messungen) zeigte sich, dass Herausforderungs-Stressoren – vermittelt über Bedeutungserleben und Vitalität – inkonsistente indirekte Beziehungen zur abhängigen Variablen Hingabe aufweisen. Die divergenten Pfade der Herausforderungs-Stressoren können erklären, weshalb Studien keinen Haupteffekt von Herausforderungs-Stressoren auf motivationale Outcomes finden konnten. In der dritten Studie wurde das Spillover-Crossover Modell aus einer Innersubjekt-Perspektive untersucht. In zeitverzögerten Mehrebenen-Pfadmodellen (211 Zweiverdiener-Paare, 1530 Arbeitstage) zeigte sich, dass situative Variationen in Anforderungen und Ressourcen – seriell vermittelt über affektives Wohlbefinden am Arbeitsplatz und partnerschaftliche Interaktionen – das affektive Wohlbefinden beider Partner am Tagesende vorhersagen. Die theoretischen und praktischen Implikationen der drei Studien sowie die Vorteile und Nachteile der Methode des ambulanten Assessments werden diskutiert.