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121.
Simon Gächter 《Research Policy》2010,39(7):893-906
Incentives to innovate are a central element of innovation theory. In the private-investment model, innovators privately fund innovation and then use intellectual property protection mechanisms to appropriate returns from these investments. In the collective-action model, public subsidy funds public goods innovations, characterized by non-rivalry and non-exclusivity in using these innovations. Recently, these models have been compounded in the private-collective innovation model where innovators privately fund public goods innovations. Private-collective innovation is illustrated in the case of open source software development. This paper contributes to the work on this model by investigating incentives that motivate innovators to share their knowledge in an initial situation, before there is a community to support the innovation process. We use game theory to predict knowledge sharing behavior in private-collective innovation, and test these predictions in a laboratory setting. The results show that knowledge sharing is a coordination game with multiple equilibria, reflecting the fragility of knowledge sharing between innovators with conflicting interests. The experimental results demonstrate important asymmetries in the fragility of knowledge sharing and, in some situations, more knowledge sharing than theoretically predicted. A behavioral analysis suggests that knowledge sharing in private-collective innovation is not only affected by material incentives, but also by social preferences such as fairness. The results offer general insights into the relationship between incentives and knowledge sharing and contribute to a better understanding of the initiation of private-collective innovation. 相似文献
122.
How can clusters sustain performance? The role of network strength, network openness, and environmental uncertainty 总被引:2,自引:0,他引:2
This paper draws on social network theory to develop a model of regional cluster performance. We suggest that high performing regional clusters are underpinned by (1) network strength and (2) network openness, but that the effects of these on the performance of a cluster as a whole are moderated by environmental uncertainty. Specifically, the positive effects of network openness on cluster performance tend to increase as environmental uncertainty increases, while the positive effects of network strength on cluster performance tend to decrease as environmental uncertainty increases. Our findings have theoretical and practical implications for social network research in general, and cluster research in particular. 相似文献
123.
This paper asks two - relatively simple - questions: can cities shape socio-technical transitions? And how would we know if they were? There are three key objectives. The first of these is to set out emerging, and in our view, convincing evidence, that large world cities have political aspirations to develop purposive and managed change in the socio-technical organisation of infrastructure networks that can be characterised as ‘systemic’ transitions. The second objective is conceptual in orientation and seeks to address how we understand transitions at the scale of the city, the role of ‘the city’ in undertaking transitions, and review both the strengths and shortcomings of the multi-level perspective (MLP) on socio-technical transitions in addressing this. The third objective is to identify what an urban transition would look like, and then constructs a new framework to conceptualise and research urban transitions. The paper then summarises the key aspects and implications of our argument. 相似文献
124.
Current awareness services are designed to keep users informed about recent developments based around user need profiles. In organisational settings, they may operate through both electronic and social interactions aimed at delivering information that is relevant, pertinent and current. Understanding these interactions can reveal the tensions in current awareness dissemination and help inform ways of making services more effective and efficient. We report an in-depth, observational study of electronic current awareness use within a large London law firm. The study found that selection, re-aggregation and forwarding of information by multiple actors gives rise to a complex sociotechnical distribution network. Knowledge management staff act as a layer of “intelligent filters” sensitive to complex, local information needs; their distribution decisions address multiple situational relevance factors in a situation fraught with information overload and restrictive time-pressures. Their decisions aim to optimise conflicting constraints of recall, precision and information quantity. Critical to this is the use of dynamic profile updates which propagate back through the network through formal and informal social interactions. This supports changes to situational relevance judgements and so allows the network to ‘self-tune’. These findings lead to design requirements, including that systems should support rapid assessment of information items against an individual’s interests; that it should be possible to organise information for different subsequent uses; and that there should be back-propagation from information consumers to providers, to tune the understanding of their information needs. 相似文献
125.
A. Supriya Simon D. Dinesh Roy V. Jayapal T. Vijayakumar 《Indian journal of clinical biochemistry : IJCB》2010,25(2):164-168
Cardiometabolic syndrome is one of the major public health issues of this century which describes a cluster of clinical characteristics.
Seventy two patients with coronary artery disease (CAD) and cardiometabolic syndrome and forty healthy age and sex matched
normal controls were selected for this study. Detailed clinical epidemiological and anthropometric characteristics were noted.
Lipid profile and Cytokinesis-block micronuclei (CBMN) assay using cytochalasin B were carried out in all the subjects. Serum
total cholesterol, triglyceride and LDL-cholesterol was significantly higher and HDL cholesterol was significantly lower in
patients compared to their normal counter-parts (P<0.05). CBMN frequency of the patients was significantly higher at all ages
compared to their normal counter parts (P<0.05). Various risk factors like diabetes, hypertension, dyslipidemia, abdominal
obesity, smoking and alcoholism were found influenced the CBMN frequency; but the changes were not significant. From this
study it can be concluded that DNA damage was found to be higher in patients with cardiometabolic syndrome which may be attributed
to the generation of free radicals associated with alcohol consumption, tobacco use, dyslipidemia and glucose intolerance
and the accumulation of free radicals with increase in age. 相似文献
126.
127.
In this study, we examined whether reward contrast influences choice between delayed and probabilistic outcomes. Specifically,
we predicted that the subjective value of an intermediate reward would seem relatively larger or smaller, respectively, if
it followed choices involving a smaller or larger reward and would produce corresponding changes in rates of delay and probability
discounting. In Experiment 1, subjects made choices about hypothetical 5,000 or5,000 or 50 outcomes and then made choices about
500 outcomes. Delay-discounting rates for the500 outcomes. Delay-discounting rates for the 500 outcome were larger for Group 5,000 than for Group5,000 than for Group 50, whereas the opposite
result was obtained for probability-discounting rates. In Experiment 2, we used a design that allowed for contrast effects
to be assessed within subjects. Two groups made choices about delayed or probabilistic rewards. After completing question
blocks in which the amount was 5,000 or5,000 or 50, subjects responded to questions with an intermediate amount (475/475/525). For
Group Delay, the present value of the intermediate reward was greater after the 50 block than after the50 block than after the 5,000 block, whereas
the opposite was obtained for Group Probability. The results from both experiments confirmed the predictions of reward contrast
and suggested that the subjective value of a monetary reward varies inversely with the prior reward amount. 相似文献
128.
129.
Simon D. Angus Judith Watson 《British journal of educational technology : journal of the Council for Educational Technology》2009,40(2):255-272
While a number of studies have been conducted on the impact of online assessment and teaching methods on student learning, the field does not seem settled around the promised benefits of such approaches. It is argued that the reason for this state of affairs is that few studies have been able to control for a number of confounding factors in student performance. We report on the introduction of a regular (every 3 weeks) low-mark online assessment tool in a large, first-year business mathematics course at the University of New South Wales, a major Australian university. Using a retrospective regression methodology together with a very large and rich data set, we test the proposition that exposure to the online assessment instrument enhances student learning. Significantly, we are able to control for prior student aptitude, in-course mastery, gender and even effort via a voluntary class attendance proxy. Furthermore, the study incorporates two large, and statistically diverse cohorts as well as manipulations in the model tested to robustly examine the outcomes. Our central result is that higher exposure to the online instrument robustly leads to higher student learning, all else being equal. Various implications for online assessment design, implementation and targeting are also discussed. 相似文献
130.
Amanda Berry John Loughran Kathy Smith Simon Lindsay 《Research in Science Education》2009,39(4):575-594
This paper reports research from a three-year Australian science teacher professional learning project, the Science Teaching
and Learning (STaL) Project, in which groups of science teacher participants (across years K – 12) worked with academics over
a one-year period as teacher researchers. Through reflecting on their experiences within the STaL Project and collecting data
from their classrooms related to specific science teaching concerns, teacher participants constructed cases around particular
aspects of their professional learning. The cases that these participants developed elicited rich insights into their teaching
and their students’ learning of science. This paper discusses how the cases were developed by the teacher researcher participants
and uses exemplars as a way of illustrating the nature of the professional knowledge developed. 相似文献