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191.
The temporal generalization gradient produced by the peak-interval (PI) procedure reflects behavior under the control of positive
reinforcement for responding after the criterial time, but shows negligible discouragement for early responses. The lack of
consequences for premature responding may affect estimates of timing accuracy and precision in the PI procedure. In two experiments,
we sought to encourage more accurate timing in pigeons by establishing an opportunity cost for such responding. Concurrent
ratio and interval schedules of reinforcement reduced the dispersion of keypecking around the target time. A sequence of three
response-rate states (low-high-low) characterized performance in individual trials. Opportunity cost substantially reduced
the mean and standard deviation of the duration of the middle-high state that typically enveloped the target time, indicating
improved temporal acuity. We suggest a model as a first-order approximation to timing with opportunity cost. 相似文献
192.
Wine is one of the most important Italian export products, and Nebbiolo is one of the most respected Italian grapes. In the summer of 2007, a measurement campaign was carried out in a Nebbiolo vineyard located in Vezza d'Alba, near Cuneo, Italy. Using a gauge of trade gases and some other instruments, we recorded the stomatal conductance and also some physiological parameters useful for estimating the dependence of stomatal conductance on environmental variables. The goal of this experiment was improving the parameterization of grapevine evapotranspiration through the assessment of the stomatal conductance and, in particular, of the functional dependence of the stomatal conductance on the following variables: the photosynthetically active radiation, the atmospheric temperature, the atmospheric moisture deficit, and the carbon dioxide concentration. The observations allowed us to check and, in some cases, to adapt the existing general parameterizations found in literature. The results showed some significant differences with the existing parameterizations concerning the atmospheric temperature, the atmospheric moisture deficit, and the carbon dioxide concentration. The parameterizations obtained in this experiment, although referring to a specific plant and site (namely the Nebbiolo at Vezza d'Alba), could allow assessment of the best environmental conditions under which the Nebbiolo grapevine production is the best, and in future could be tested for other grapevines or climates. 相似文献
193.
The sporting success of athletes and national teams is associated with a feel-good-factor among the population. These positive social effects can be regarded as public goods that entail a certain value for the population. The value of public or non-market goods can be estimated using the contingent valuation method (CVM). A theoretical model is developed based on the consumption capital theory. This model explains the willingness-to-pay (WTP) for winning the 2010 Football World Cup as a function of sport-related and football-specific consumption capital as well as intangible and socio-economic factors. Within a survey of German citizens (n = 3049), the value of winning the 2010 Football World Cup is assessed using CVM. The model is tested using regression analyses to identify the significant determinants of WTP. The results reveal half of the respondents stated a WTP that amounted to €26 on average. The findings of a mixed-effects logistic as well as an alternative Tobit regression model show that intangible factors such as identification with the country and with the national team as well as individual and national importance of a good result significantly influence individuals’ WTP. Based on the findings of this study, it can be recommended that policy makers invest in national teams and athletes as national sporting success can generate a feel-good-factor among the population and make people happier. Additionally, it can impact on peoples’ perceptions and expectations about current and future economic situations which in turn determine macro-economic outcomes. Moreover, such estimations could be integrated into cost-benefit terms that are carried out for sport events. 相似文献
194.
Koumoula A Tsironi V Stamouli V Bardani I Siapati S Annika G Kafantaris I Charalambidou I Dellatolas G von Aster M 《Journal of learning disabilities》2004,37(5):377-388
The aim of this study was to validate and standardize an instrument for the diagnosis of developmental dyscalculia (mathematics disorder) in a Greek population and to obtain relevant epidemiological data. We used the Neuropsychological Test Battery for Number Processing and Calculation in Children (NUCALC) in a community sample of 240 students ages 7 to 11 years from urban and rural schools. There were no differences between genders in arithmetical performance; however, the effects of grade and socioeconomic level were significant. Prevalence was higher in the rural than in the urban area. A cross-cultural comparison of the Greek data with those obtained with the same instrument in other countries in schoolchildren of the same age was performed. 相似文献
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Marcel Verhoeven M. Bjørn von Rimscha Isabelle Krebs Gabriele Siegert Christoph Sommer 《媒体管理杂志》2018,20(1):51-77
Research on media success factors is a fragmented field. Definitions, measures, and methods vary, and findings are often inconsistent. In an attempt to fill this perceived research gap, we distilled generic success factors of media products from the literature. Guided by theory and empirical findings, these factors were aggregated to complex concepts, building blocks of success that we further investigated in an exploratory qualitative study. We found that the building blocks are applicable to all types of media, independent of seriality and content types of media products. Subsequently the research question of this article is: Which building blocks of success are most important for media products? To answer this question, we conducted an online survey of 255 media professionals in print, audio-visual, and online media in Austria, Germany and Switzerland. To analyze our data, we deployed qualitative comparative analysis, a method based on set theory that is suitable to investigate complex causality. We conclude that four building blocks are necessary for success: “good” distribution, environmental orientation, form/design, and human resources are preconditions for achieving success in terms of audience market share. In addition, three patterns emerge in the sufficient paths (combinations of building blocks) to success. Which route to success a media product shows can be related to the width of its topical scope and the corresponding projected audience size. 相似文献
198.
Federico Mayor 《Higher Education in Europe》2004,29(4):491-494
The author considers in this article the ethical boundaries of knowledge, the challenges inherent in the improvement of international ethical and legal frameworks, and some of the ethically important moments of the past half‐century. Implications for higher education in the context of globalization are also considered, as are some of the new educational requirements of the knowledge‐driven economy and society. 相似文献
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Romero-Maltrana Diego Benitez Federico Vera Francisco Rivera Rodrigo 《Research in Science Education》2019,49(6):1735-1757
Research in Science Education - There is an increasing demand in the field of science education for the incorporation of philosophical and sociological aspects that are related to the scientific... 相似文献