6,732 research outputs found
University Public-Access Mandates Are Good for Science
A new and better order to make scholarship available for free to all is emerging through deposit mandates like those adopted by Harvard, MIT, and Kansas
The role of research in higher education: implications and challenges for an active future contribution to human and social development
Mankind is on the brink of a tragic era, in which the anarchic forces of the market and the incessant pressures upon natural resources on the verge of exhaustion will push sovereign states to increasingly dangerous rivalries. What will the role of research in higher education be, in response to the challenge of an active future contribution to human and social development? A good balance must be reached in the basic functions of research in order to avoid governance risks. While focusing only on the transformative function of research may pose dangers to the human dimension and development, unilateral concentration on responsible development aspects may generate reactive approaches and delay economic benefits. Disregarding the inclusiveness function may lead to slower development and even isolationism, and focusing on short-term issues is not good for long-term goals and future generations. We must reinforce research networks between âSouthernâ and âNorthernâ, rich and poor, and developed and developing countries and institutions in order to bridge the gap between knowledge consumers and producers. This paper reviews aspects such as development, globalization and the inequality of nations; constraints and choices of the orthodox views of research; rethinking research and higher education to contribute to a better future; and knowledge integration for effective action.Peer Reviewe
Life, Death and Preferential Attachment
Scientific communities are characterized by strong stratification. The highly
skewed frequency distribution of citations of published scientific papers
suggests a relatively small number of active, cited papers embedded in a sea of
inactive and uncited papers. We propose an analytically soluble model which
allows for the death of nodes. This model provides an excellent description of
the citation distributions for live and dead papers in the SPIRES database.
Further, this model suggests a novel and general mechanism for the generation
of power law distributions in networks whenever the fraction of active nodes is
small.Comment: 5 pages, 2 figure
Belief in conspiracy theories and intentions to engage in everyday crime
Belief in conspiracy theories is associated with negative outcomes such as political disengagement, prejudice, and environmental inaction. The current studies - one cross-sectional (N = 253) and one experimental (N = 120) - tested the hypothesis that belief in conspiracy theories would increase intentions to engage in everyday crime. Study 1 demonstrated that belief in conspiracy theories predicted everyday crime behaviours when controlling for other known predictors of everyday crime (e.g., Honesty-Humility). Study 2 demonstrated that exposure to conspiracy theories (vs. control) increased intentions to engage in everyday crime in the future, through an increased feeling of anomie. The perception that others have conspired may therefore in some contexts lead to negative action rather than inaction
Power Utility Maximization in Discrete-Time and Continuous-Time Exponential Levy Models
Consider power utility maximization of terminal wealth in a 1-dimensional
continuous-time exponential Levy model with finite time horizon. We discretize
the model by restricting portfolio adjustments to an equidistant discrete time
grid. Under minimal assumptions we prove convergence of the optimal
discrete-time strategies to the continuous-time counterpart. In addition, we
provide and compare qualitative properties of the discrete-time and
continuous-time optimizers.Comment: 18 pages, to appear in Mathematical Methods of Operations Research.
The final publication is available at springerlink.co
Exposure-Based Cash-Flow-At-Risk for Value-Creating Risk Management Under Macroeconomic Uncertainty
A strategically minded CFO will realize that strategic corporate risk management is about finding the right balance between risk prevention and proactive value generation. Efficient risk and performance management requires adequate assessment of risk and risk exposures on the one hand and performance on the other. Properly designed, a risk measure should provide information on to what extend the firm's performance is at risk, what is causing that risk, the relative importance of non-value-adding and value-adding risk, and the possibilities to use risk management to reduce total risk. In this chapter, we present an approach exposure-based cash-flow-at-risk to calculating a firm's downside risk conditional on the firm's exposure to non-value-adding macroeconomic and market risk and to analyzing corporate performance adjusted for the impact of non-value-adding risk
Engineering serendipity: When does knowledge sharing lead to knowledge production?
Research Summary
We investigate how knowledge similarity between two individuals is systematically related to the likelihood that a serendipitous encounter results in knowledge production. We conduct a field experiment at a medical research symposium, where we exogenously varied opportunities for faceâtoâface encounters among 15,817 scientistâpairs. Our data include direct observations of interaction patterns collected using sociometric badges, and detailed, longitudinal data of the scientists\u27 postsymposium publication records over 6âyears. We find that interacting scientists acquire more knowledge and coauthor 1.2 more papers when they share some overlapping interests, but cite each other\u27s work between three and seven times less when they are from the same field. Our findings reveal both collaborative and competitive effects of knowledge similarity on knowledge production outcomes. Managerial Summary
Managers often try to stimulate innovation by encouraging serendipitous interactions between employees, for example by using office space redesigns, conferences and similar events. Are such interventions effective? This article proposes that an effective encounter depends on the degree of common knowledge shared by the individuals. We find that scientists who attend the same conference are more likely to learn from each other and collaborate effectively when they have some common interests, but may view each other competitively when they work in the same field. Hence, when designing opportunities for faceâtoâface interactions, managers should consider knowledge similarity as a criteria for fostering more productive exchanges
Stochastic Cellular Automata Model for Stock Market Dynamics
In the present work we introduce a stochastic cellular automata model in
order to simulate the dynamics of the stock market. A direct percolation method
is used to create a hierarchy of clusters of active traders on a two
dimensional grid. Active traders are characterised by the decision to buy,
(+1), or sell, (-1), a stock at a certain discrete time step. The remaining
cells are inactive,(0). The trading dynamics is then determined by the
stochastic interaction between traders belonging to the same cluster. Most of
the stylized aspects of the financial market time series are reproduced by the
model.Comment: 17 pages and 7 figure
In vitro production of bovine embryos derived from individual donors in the CorralÂź dish
Background: Since the identity of the embryo is of outmost importance during commercial in vitro embryo production, bovine oocytes and embryos have to be cultured strictly per donor. Due to the rather low yield of oocytes collected after ovum pick-up (OPU) per individual cow, oocyte maturation and embryo culture take place in small groups, which is often associated with inferior embryo development. The objective of this study was to improve embryonic development in small donor groups by using the Corral (R) dish. This commercial dish is designed for human embryo production. It contains two central wells that are divided into quadrants by a semi-permeable wall. In human embryo culture, one embryo is placed per quadrant, allowing individual follow-up while embryos are exposed to a common medium. In our study, small groups of oocytes and subsequently embryos of different bovine donors were placed in the Corral (R) dish, each donor group in a separate quadrant.
Results: In two experiments, the Corral (R) dish was evaluated during in vitro maturation (IVM) and/or in vitro culture (IVC) by grouping oocytes and embryos of individual bovine donors per quadrant. At day 7, a significantly higher blastocyst rate was noted in the Corral (R) dish used during IVM and IVC than when only used during IVM (12.9% +/- 2.10 versus 22.8% +/- 2.67) (P < 0.05). However, no significant differences in blastocyst yield were observed anymore between treatment groups at day 8 post insemination.
Conclusions: In the present study, the Corral (R) dish was used for in vitro embryo production (IVP) in cattle; allowing to allocate oocytes and/or embryos per donor. As fresh embryo transfers on day 7 have higher pregnancy outcomes, the Corral (R) dish offers an added value for commercial OPU/IVP, since a higher blastocyst development at day 7 is obtained when the Corral (R) dish is used during IVM and IVC
Growing with the market : how changing conditions during market growth affect formation and evolution of interfirm ties
Research Summary:
Market conditions are known to matter for firm performance and growth. This study explores how changing levels of uncertainty and competition affect interfirm ties of entrepreneurial firms as markets transition from nascent to growth stage. Tracing 6 entrepreneurial game publishers during the growth stage of the US wireless gaming market, the findings reveal that in a growth stage market, as uncertainty decreases, certain ties of entrepreneurial firms are terminated. First, existing partners may cut ties and become competitors after entering the market directly. This is a âwinner's curseâ as more successful firms are more likely to entice their partners to enter the market directly. Second, ties may be terminated as prominent firms that are âoverwhelmedâ with too many partners cut ties with low to mediocre performance while their remaining partners enter a positive spiral of tie strength and performance. Finally, as uncertainty decreases, new firms may enter the market as competitors to prominent firms. While entrepreneurial firms with high and low performing ties to prominent partners may find ties with these new entrants attractive, those with mediocre ties to few prominent partners find this move too risky and wait for a first mover to legitimate it. Overall, the findings show that changing levels of uncertainty and competition in growth stage markets can have different consequences for firms due to heterogeneity in their ties and power relative to partners. The findings provide several contributions to literature regarding the relationship between interfirm ties, firm performance, and market evolution.
Managerial Summary:
Based on interviews at 6 entrepreneurial game publishers in the US and their partners, this study shows how changing levels of uncertainty and competition in growing markets can have different consequences for firms based on the different types of alliances in their portfolio and their power relative to partners. The findings highlight the importance of managing partners differently based on alliance type and goal of the partner. They advocate remaining flexible in alliance management as information asymmetries, intentions and bargaining power of partners can change and lead to abrupt alliance dissolution. They show that alliance portfolio management goes beyond a firm's capability of managing individual alliances, and provide a tool for managers to evaluate their alliance portfolios and take the necessary precautions
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