499 research outputs found
Power-law weighted networks from local attachments
This letter introduces a mechanism for constructing, through a process of
distributed decision-making, substrates for the study of collective dynamics on
extended power-law weighted networks with both a desired scaling exponent and a
fixed clustering coefficient. The analytical results show that the connectivity
distribution converges to the scaling behavior often found in social and
engineering systems. To illustrate the approach of the proposed framework we
generate network substrates that resemble steady state properties of the
empirical citation distributions of (i) publications indexed by the Institute
for Scientific Information from 1981 to 1997; (ii) patents granted by the U.S.
Patent and Trademark Office from 1975 to 1999; and (iii) opinions written by
the Supreme Court and the cases they cite from 1754 to 2002.Comment: 18 pages, 3 figures; Proceedings of the IEEE Conference on Decision
and Control and the European Control Conference, Orlando, FL, Dec. 2011;
Added references; We modified the model in order to take into account
extended power-law distributions which better fit to the citations data sets;
Added proofs of theorems; Shorten version; Updated plo
Consistency and trends of technological innovations: a network approach to the international patent classification data
Classifying patents by the technology areas they pertain is important to enable information search and facilitate policy analysis and socio-economic studies. Based on the OECD Triadic Patent Family database, this study constructs a cohort network based on the grouping of IPC subclasses in the same patent families, and a citation network based on citations between subclasses of patent families citing each other. This paper presents a systematic analysis approach which obtains naturally formed network clusters identified using a Lumped Markov Chain method, extracts community keys traceable over time, and investigates two important community characteristics: consistency and changing trends. The results are verified against several other methods, including a recent research measuring patent text similarity. The proposed method contributes to the literature a network-based approach to study the endogenous community properties of an exogenously devised classification system. The application of this method may improve accuracy and efficiency of the IPC search platform and help detect the emergence of new technologies
Liquidity, technological opportunities, and the stage distribution of venture capital investments
This paper explores the determinants of the stage distribution of European venture capital investments from 1990 to 2011. Consistent with liquidity risk theory, we find that the likelihood of investing in earlier stages increases relative to all private equity investments during liquidity crisis years. While liquidity is the main driver of acquisition investments and, to some extent, of expansion financings, technological opportunities are overall the main driver of early and late stage venture capital investments. In contrast to the dotcom crash, the recent financial crisis negatively affected the relative likelihood of expansion investments, but not of early and late stage investments
Traumatic brain injuries and problem gambling in youth: Evidence from a population-based study of secondary students in Ontario, Canada
Traumatic brain injury (TBI) is characterized by a change in brain function after an external force or sudden movement to the head. TBI is associated with risk-taking, impulsivity, psychological distress, substance abuse, and violent crime. Previous studies have also linked problem gambling to TBI, but these studies have not controlled for possible confounding variables such as mental health problems and hazardous drinking which are also linked to TBI. This study examines the relationship between problem gambling and TBI among adolescents. Data were obtained from the 2011, 2013 and 2015 cycles of the OSDUHS, a biennial cross-sectional school-based study of children in grades 7 to 12 (N = 9,198). Logistic regression was used to estimate adjusted odds ratios (AOR) in controlled and uncontrolled analyses. Adjusting for sex and grade only, problem gambling was associated with a history of TBI (AOR = 2.8). This association remained significant after adjusting for hazardous drinking and suicidality (AOR = 2.0). In addition, problem gambling had a statistically significant relationship with being male (AOR = 4.7), hazardous drinking (AOR = 4.5), and suicidality (AOR = 3.1). This study provides further data to suggest a link between TBI and problem gambling. However, research is needed on the causal relationship between these variables and the potential implications for treatment and prevention
How citation boosts promote scientific paradigm shifts and Nobel Prizes
Nobel Prizes are commonly seen to be among the most prestigious achievements
of our times. Based on mining several million citations, we quantitatively
analyze the processes driving paradigm shifts in science. We find that
groundbreaking discoveries of Nobel Prize Laureates and other famous scientists
are not only acknowledged by many citations of their landmark papers.
Surprisingly, they also boost the citation rates of their previous
publications. Given that innovations must outcompete the rich-gets-richer
effect for scientific citations, it turns out that they can make their way only
through citation cascades. A quantitative analysis reveals how and why they
happen. Science appears to behave like a self-organized critical system, in
which citation cascades of all sizes occur, from continuous scientific progress
all the way up to scientific revolutions, which change the way we see our
world. Measuring the "boosting effect" of landmark papers, our analysis reveals
how new ideas and new players can make their way and finally triumph in a world
dominated by established paradigms. The underlying "boost factor" is also
useful to discover scientific breakthroughs and talents much earlier than
through classical citation analysis, which by now has become a widespread
method to measure scientific excellence, influencing scientific careers and the
distribution of research funds. Our findings reveal patterns of collective
social behavior, which are also interesting from an attention economics
perspective. Understanding the origin of scientific authority may therefore
ultimately help to explain, how social influence comes about and why the value
of goods depends so strongly on the attention they attract.Comment: 6 pages, 6 figure
Capacidad innovadora de la Comunidad de Madrid a partir de las patentes concedidas entre 1996 y 2007
Structural versus experienced complexity: a new perspective on the relationship between organizational complexity and innovation
In this paper, we explore the relationship between organizational complexity and firm-level innovation. We define and operationalize a new construct, experienced complexity, which is the extent to which the organizational environment makes it challenging for decision-makers to do their jobs effectively. We distinguish experienced complexity from structural complexity, which is the elements of the organization, such as the number of reporting lines or integrating mechanisms, that are deliberately put in place to help the organization deliver on its objectives, and we argue that structural complexity correlates positively with firm-level innovation while experienced complexity correlates negatively with innovation. Using a novel dataset combining survey and objective data on 209 large firms, we find support for our arguments
Technological diversification within UK’s small serial innovators
This paper investigates the determinants of technological diversification among UK’s small serial innovators (SSIs). Using a longitudinal study of 339 UK-based small businesses accounting for almost 7000 patents between 1990 and 2006, this study constitutes the first empirical examination of technological diversification among SMEs in the literature. Results demonstrate that technological diversification is not solely a large firm activity, challenging the dominant view that innovative SMEs are extremely focused and specialised players with little technological diversification. Our findings suggest a nonlinear (i.e. inverse-U-shaped) relationship between the level of technological opportunities in the environment and the SSIs’ degree of technological diversification. This points to a trade-off between processes of exploration and exploitation across increasingly volatile technology regimes. The paper also demonstrates that small firms with impactful innovations focus their innovative activity around similar technological capabilities while firms that have introduced platform technologies in the past are more likely to engage in technological diversification
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