Perfils. Randy Barker: mestre de metges

Randy Barker (EUA, 1939) és metge i professor al Johns Hopkins Bayview Medical Center de Baltimore, als Estats Units. El Centre ha estat un dels primers a fer del learning by doing un element programàtic, filosofia que, d’alguna manera, comparteix fonaments amb l’aprenentatge basat en problemes (ABP). Barker visita Girona perquè és membre del Consell Acadèmic Internacional de la Facultat de Medicina de la UdG, en la qual, a més, ha impartit la lliçó magistral Professionalisme i ensenyament de la medicina

Linguistic relativity in SLA: towards a new research programme

The purpose of the current article is to support the investigation of linguistic relativity in second language acquisition and sketch methodological and theoretical prerequisites toward developing the domain into a full research program. We identify and discuss three theoretical-methodological components that we believe are needed to succeed in this enterprise. First, we highlight the importance of using nonverbal methods to study linguistic relativity effects in second language (L2) speakers. The use of nonverbal tasks is necessary in order to avoid the circularity that arises when inferences about nonverbal behavior are made on the basis of verbal evidence alone. Second, we identify and delineate the likely cognitive mechanisms underpinning cognitive restructuring in L2 speakers by introducing the theoretical framework of associative learning. By doing so, we demonstrate that the extent and nature of cognitive restructuring in L2 speakers is essentially a function of variation in individual learners’ trajectories. Third, we offer an in-depth discussion of the factors (e.g., L2 proficiency and L2 use) that characterize those trajectories, anchoring them to the framework of associative learning, and reinterpreting their relative strength in predicting L2 speaker cognition

Multimedial instruktionsmetodik : en fallstudie kring multimedia i undervisningen

Multimedia är ett hett omdebatterat ämne både i och utanför skolan. Vad är det bra för och hur kan man använda det i undervisningen? Den frågan kan man finna svaret på i detta arbete genom att läsa detta arbete.Vi ger bakgrundsmaterial i form av en kvantitativ attitydundersökning kring lärare och IT.Syftet med detta arbete är att bidra till skolutveckling genom att lyfta fram didaktiska metoder inom multimedial instruktionsmetodik. Vidare kommer vi att försöka få ett svar på hur de förhåller sig till att använda sig av multimediala hjälpmedel i sin undervisning.Undersökningens metod har varit kvalitativa intervjuer med 11 informanter. Dessa kommer både från högskola och gymnasieskola. Informanterna kommer från olika pedagogiska yrken så som högskoleadjunkt, yrkeslärare, lektor och kärnämneslärare.I våra teoretiska utgångspunkter klargörs diskursen för detta examensarbete. Under inlärning beskrivs olika utvecklingspsykologiska teorier. Där beskrivs bland annat multimedia principen och lärstilar .Ur resultatet framkommer att användning av multimedia ser olika ut och att instruktionsanvändandet stämmer överens med våra teoretiska utgångspunkter.Vidare diskuteras mer generella aspekter av multimedial inlärning samt hur undervisning kan organiseras och genomföras med olika presentationshjälpmedel. Genom att använda multimedia i undervisningen får man variation, som gynnar helhetsbilden kring olika lärstilar.Multimedial instruktionsmetodik handlar om hur och varför man kan och bör använda multimediala hjälpmedel för att förbättra undervisningen. Vi belyser teorier som understödjer ett multimedialt användande inom undervisning. Vår fallstudie undersöker lärares användning och ger lärande exempel på multimedial instruktionsmetodik. Under diskussionen framkommer fler intressanta lärande exempel. Här finns också hänvisningar till tänkbara multimediala inspirationskällor. En sammanställning för fortsatt forskning inom området finns att tillgå i form av en bilaga.Slutligen ges förslag till framtida forskning inom området för detta examensarbete.

Relação entre produtividade total dos fatores e investimento em capital fixo para a economia brasileira

O presente trabalho utiliza a teoria do crescimento econômico a fim de analisar a relação das taxas de investimento em capital fixo e a evolução da produtividade total dos fatores no Brasil a partir de 1950 ate 2005. A partir de pesquisas bibliográficas abordam-se os estudos de Romer, Arrow, Pires, Solow se apresenta conceitos como o “learning by doing”, “spillovers” e decomposição da produtividade a fim de embasar teoricamente o estudo. As pesquisas apontam a importância da variável eficiência sobre a produtividade total dos fatores no caso brasileiro, principalmente durante os anos de incidência de inflação elevada. A metodologia aplicada no trabalho se utiliza dos dados coletados junto ao IPEAdata e Pen World Tables para formação bruta de capital fixo, produto interno bruto e dados populacionais para o cálculo da produtividade total dos fatores seguindo a metodologia proposta por Solow. Utilizam-se os dados calculados para se extrair uma relação matemática entre a produtividade total dos fatores e ao nível de estoque de capital físico. O estudo comprova a relação entre a produtividade e o investimento em capital físico, também fica demonstrada a grande importância da eficiência sobre a produtividade no caso brasileiro.

Career concerns: a human capital perspective

We introduce human capital accumulation, in the form of learning by doing, in a life cycle model of career concerns and analyze how human capital acquisition a ects implicit incentives for performance. We show that standard results from the career concerns literature can be reversed in the presence of human capital accumulation. Namely, implicit incentives need not decrease over time and may decrease with the degree of uncertainty about an individual's talent. Furthermore, increasing the pre-cision of output measurement can weaken rather than strengthen implicit incentives. Overall, our results contribute to shed new light on the ability of markets to discipline moral hazard in the absence of explicit contracts linking pay to performance.

La capacidad innovativa y el fortalecimiento de la competitividad de las firmas: el caso de las PYMEs exportadoras argentinas

Incluye Bibliografía

An empirical analysis of technology absorption capacity of the Brazilian industry

Includes bibliography.

O pólo industrial de Manaus como modelo de desenvolvimento econômico avaliado sob o enfoque da Lei de Kaldor-Verdoorn

Este estudo tem como objetivo mensurar e avaliar a dinâmica econômica do Pólo Industrial de Manaus como um modelo de desenvolvimento sob o enfoque da Lei de kaldor-Verdoorn. Especificamente, analisar a relação entre produção e produtividade, sob as condições preconizadas por esta lei, aplicadas às indústrias do Pólo Industrial de Manaus. A Lei de Kaldor-Verdoorn propõe que à medida que a produção aumenta, há uma forte tendência, ao longo do tempo, de crescimento da produtividade. Economias de escala são geradas endogenamente por mudança técnica e aprendizagem tecnológica (learning by doing), fruto do crescimento da demanda que permite que se explore as economias de escala dinâmicas presentes, principalmente, no setor manufatureiro. Dessa forma, estima-se a produtividade total de fatores e a produtividade parcial. Analisa-se a dinâmica dessa economia efetuando-se teste empírico para a indústria do Pólo Industrial de Manaus, no período de janeiro de 1995 a dezembro de 2004, através de um modelo de correção de erros, teste de causalidade de Granger e modelo VAR estrutural,. Os resultados obtidos indicam um razoável grau de dinamismo dessa economia, dado que a combinação de efeitos de curto e longo prazo fez com que a produtividade crescesse num ritmo mais acelerado, com respostas rápidas no curto prazo, da produtividade a choques de mudanças no valor total da produção e emprego. Comprovam também a existência de fontes endógenas de crescimento da produtividade, evidenciando economias de escala crescente.

Rationale, scope, and 20-year experience of vascular surgical training with lifelike pulsatile flow models

Vascular surgical training currently has to cope with various challenges, including restrictions on work hours, significant reduction of open surgical training cases in many countries, an increasing diversity of open and endovascular procedures, and distinct expectations by trainees. Even more important, patients and the public no longer accept a "learning by doing" training philosophy that leaves the learning curve on the patient's side. The Vascular International (VI) Foundation and School aims to overcome these obstacles by training conventional vascular and endovascular techniques before they are applied on patients. To achieve largely realistic training conditions, lifelike pulsatile models with exchangeable synthetic arterial inlays were created to practice carotid endarterectomy and patch plasty, open abdominal aortic aneurysm surgery, and peripheral bypass surgery, as well as for endovascular procedures, including endovascular aneurysm repair, thoracic endovascular aortic repair, peripheral balloon dilatation, and stenting. All models are equipped with a small pressure pump inside to create pulsatile flow conditions with variable peak pressures of ~90 mm Hg. The VI course schedule consists of a series of 2-hour modules teaching different open or endovascular procedures step-by-step in a standardized fashion. Trainees practice in pairs with continuous supervision and intensive advice provided by highly experienced vascular surgical trainers (trainer-to-trainee ratio is 1:4). Several evaluations of these courses show that tutor-assisted training on lifelike models in an educational-centered and motivated environment is associated with a significant increase of general and specific vascular surgical technical competence within a short period of time. Future studies should evaluate whether these benefits positively influence the future learning curve of vascular surgical trainees and clarify to what extent sophisticated models are useful to assess the level of technical skills of vascular surgical residents at national or international board examinations. This article gives an overview of our experiences of >20 years of practical training of beginners and advanced vascular surgeons using lifelike pulsatile vascular surgical training models.

Distance measures for image segmentation evaluation

The task considered in this paper is performance evaluation of region segmentation algorithms in the ground-truth-based paradigm. Given a machine segmentation and a ground-truth segmentation, performance measures are needed. We propose to consider the image segmentation problem as one of data clustering and, as a consequence, to use measures for comparing clusterings developed in statistics and machine learning. By doing so, we obtain a variety of performance measures which have not been used before in image processing. In particular, some of these measures have the highly desired property of being a metric. Experimental results are reported on both synthetic and real data to validate the measures and compare them with others.

Impacts of FTA utilization on firm performance

The international export and investment activities of firms have been widely studied by scholars. In particular, prior studies have focused on two main hypotheses about firms engaged in international activities such as exporting and investing abroad; namely, self-selection of more productive firms into international activities and learning-by-doing international activities. This paper is the first study that explores these hypotheses in regard to firms’ use of free trade agreements (FTAs). We first estimate the propensity score for firms’ use of FTA schemes, and find that larger firms are more likely to participate. Then, by conducting matching analysis using the propensity scores, we find that the use of FTA schemes does not change employment in firms, but does result in more local inputs used and increased exports.

Gaining Insight into Actual and Preferred Sources of Coaching Knowledge

Previous research has suggested that current formal coach education programs do not fully meet the learning needs of coaches. The purpose of the present study was to examine actual and preferred sources of coaching knowledge for developmental-level coaches. Structured quantitative interviews were conducted with coaches (N = 44) from a variety of sports. Learning by doing, interaction with coaching peers, and formal coach education were the top actual sources of coaching knowledge. Discrepancies were found between actual and preferred usage of learning by doing, formal coach education, and mentoring. Coaches indicated they would prefer more guided learning and less self-directed learning by doing. Further, differences in preferred sources were identified between coaches wishing to move to an elite level versus coaches wishing to stay at a developmental level. Findings highlight the importance of both experiential and formally guided sources of coaching knowledge and the context-specific nature of coach learning.

Essays in dynamic optimal taxation: working experience, unemployment scarring and poverty

This thesis investigates the design of optimal tax systems in dynamic environments. The first essay characterizes the optimal tax system where wages depend on stochastic shocks and work experience. In addition to redistributive and efficiency motives, the taxation of inexperienced workers depends on a second-best requirement that encourages work experience, a social insurance motive and incentive effects. Calibrations using U.S. data yield higher expected optimal marginal income tax rates for experienced workers for most of the inexperienced workers. They confirm that the average marginal income tax rate increases (decreases) with age when shocks and work experience are substitutes (complements). Finally, more variability in experienced workers' earnings prospects leads to increasing tax rates since income taxation acts as a social insurance mechanism. In the second essay, the properties of an optimal tax system are investigated in a dynamic private information economy where labor market frictions create unemployment that destroys workers' human capital. A two-skill type model is considered where wages and employment are endogenous. I find that the optimal tax system distorts the first-period wages of all workers below their efficient levels which leads to more employment. The standard no-distortion-at-the-top result no longer holds due to the combination of private information and the destruction of human capital. I show this result analytically under the Maximin social welfare function and confirm it numerically for a general social welfare function. I also investigate the use of a training program and job creation subsidies. The final essay analyzes the optimal linear tax system when there is a population of individuals whose perceptions of savings are linked to their disposable income and their family background through family cultural transmission. Aside from the standard equity/efficiency trade-off, taxes account for the endogeneity of perceptions through two channels. First, taxing labor decreases income, which decreases the perception of savings through time. Second, taxation on savings corrects for the misperceptions of workers and thus savings and labor decisions. Numerical simulations confirm that behavioral issues push labor income taxes upward to finance saving subsidies. Government transfers to individuals are also decreased to finance those same subsidies.

Foreign direct investment, technology sourcing and reverse spillovers

Recent theoretical work points to the possibility of foreign direct investment motivated not by 'ownership' advantages which may be exploited by a multinational enterprise but by the desire to access the superior technology of a host nation through direct investment. To be successful, technology sourcing foreign direct investment hinges crucially on the existence of domestic-to-foreign technological externalities within the host country. We test empirically for the existence of such 'reverse spillover' effects for a panel of UK manufacturing industries. The results demonstrate that technology generated by the domestic sector spills over to foreign multinational enterprises, but that this effect is restricted to relatively research and development intensive sectors. There is also evidence that these spillover effects are affected by the spatial concentration of industry, and that learning-by-doing effects are restricted to sectors in which technology sourcing is unlikely to be a motivating influence.

Growth expectations of business owners:impact of human capital, firm characteristics and environmental transition

This paper presents an empirical study based on a survey of 399 owners of small and medium size companies in Lithuania. Applying bivariate and ordered probit estimators, we investigate why some business owners expect their firms to expand, while others do not. Our main findings provide evidence that SME owner's generic and specific human capital matter. Those with higher education and 'learning by doing' attributes, either through previous job experience or additional entrepreneurial experience, expect their businesses to expand. The expectations of growth are positively related to exporting and non-monotonically to enterprise size. In addition, we analyse the link between the perceptions of constraints to business activities and growth expectations and find that the factors, which are perceived as main business barriers, are not necessary those which are associated with reduced growth expectations. In particular, perceptions of both corruption and of inadequate tax systems seem to affect growth expectations the most.