Statistical keyword detection in literary corpora

Understanding the complexity of human language requires an appropriate analysis of the statistical distribution of words in texts. We consider the information retrieval problem of detecting and ranking the relevant words of a text by means of statistical information referring to the "spatial" use of the words. Shannon's entropy of information is used as a tool for automatic keyword extraction. By using The Origin of Species by Charles Darwin as a representative text sample, we show the performance of our detector and compare it with another proposals in the literature. The random shuffled text receives special attention as a tool for calibrating the ranking indices.Comment: Published version. 11 pages, 7 figures. SVJour for LaTeX2

How rare are diffusive rare events?

We study the time until first occurrence, the first-passage time, of rare density fluctuations in diffusive systems. We approach the problem using a model consisting of many independent random walkers on a lattice. The existence of spatial correlations makes this problem analytically intractable. However, for a mean-field approximation in which the walkers can jump anywhere in the system, we obtain a simple asymptotic form for the mean first-passage time to have a given number k of particles at a distinguished site. We show numerically, and argue heuristically, that for large enough k, the mean-field results give a good approximation for first-passage times for systems with nearest-neighbour dynamics, especially for two and higher spatial dimensions. Finally, we show how the results change when density fluctuations anywhere in the system, rather than at a specific distinguished site, are considered.Comment: 6 pages, 5 figures. Accepted for publication in Europhysics Letters (http://www.iop.org/EJ/journal/EPL

Survival and residence times in disordered chains with bias

We present a unified framework for first-passage time and residence time of random walks in finite one-dimensional disordered biased systems. The derivation is based on exact expansion of the backward master equation in cumulants. The dependence on initial condition, system size, and bias strength is explicitly studied for models with weak and strong disorder. Application to thermally activated processes is also developed.Comment: 13 pages with 2 figures, RevTeX4; v2:minor grammatical changes, typos correcte

Variation in survival after diagnosis of breast cancer in Switzerland

Background: Survival after diagnosis of cancer is a key criterion for cancer control. Major survival differences between time periods and countries have been reported by the EUROCARE studies. We investigated whether similar differences by period and region existed in Switzerland. Methods: Survival of 11 376 cases of primary invasive female breast cancer diagnosed between 1988 and 1997 and registered in seven Swiss cancer registries covering a population of 3.5 million was analysed. Results: Comparing the two periods 1988-1992 and 1993-1997, age-standardized 5 year relative survival improved globally from 77% to 81%. Furthermore, multivariate analysis adjusting for age, tumour size and nodal involvement identified regional survival differences. Survival was lowest in the rural parts of German-speaking eastern Switzerland and highest in urbanised regions of the Latin- and German-speaking northwestern parts of the country. Conclusions: This study confirms that survival differences are present even in a small and affluent, but culturally diverse, country like Switzerland, raising the issue of heterogeneity in access to care and quality of treatmen

The limited importance of size-asymmetric light competition and growth of pioneer species in early secondary forest succession in Vietnam

It is generally believed that asymmetric competition for light plays a predominant role in determining the course of succession by increasing size inequalities between plants. Size-related growth is the product of size-related light capture and light-use efficiency (LUE). We have used a canopy model to calculate light capture and photosynthetic rates of pioneer species in sequential vegetation stages of a young secondary forest stand. Growth of the same saplings was followed in time as succession proceeded. Photosynthetic rate per unit plant mass (Pmass: mol C g−1 day−1), a proxy for plant growth, was calculated as the product of light capture efficiency [Φmass: mol photosynthetic photon flux density (PPFD) g−1 day−1] and LUE (mol C mol PPFD−1). Species showed different morphologies and photosynthetic characteristics, but their light-capturing and light-use efficiencies, and thus Pmass, did not differ much. This was also observed in the field: plant growth was not size-asymmetric. The size hierarchy that was present from the very early beginning of succession remained for at least the first 5 years. We conclude, therefore, that in slow-growing regenerating vegetation stands, the importance of asymmetric competition for light and growth can be much less than is often assumed

Equal pay by gender and by nationality: a comparative analysis of Switzerland's unequal equal pay policy regimes across time

What explains the adoption of two different policies on equal pay by gender (EPG) and by nationality (EPN) in Switzerland? And why is the liberal, litigation-based, equal pay policy regime set up by the Gender Equality Act of 1996 much less effective than the neocorporatist ‘accompanying measures' to the Bilateral European Union-Switzerland Agreement on Free Movement of Persons adopted in 1999 to ensure equal pay for workers of different national origins? The formation of two different policy regimes cannot be explained by different levels of political will. Equally, different ‘varieties of capitalism' cannot explain the setup of the two different equal pay policy regimes within the very same country. Instead, our qualitative comparative analysis across time suggests that the differences can be best explained by a particular constellation of attributes, namely the use of different policy frames—i.e. ‘anti-discrimination' in the EPG and ‘unfair competition' in the EPN case—and the different setting of interest politics epitomised by the opposite stances adopted by Switzerland's employer associations in the two case

Peningkatan Kualitas Guru Bimbingan dan Konseling melalui Penguasaan Teori Realita

IMPROVING THE QUALITY OF GUIDANCE AND COUNSELING TEACHERS THROUGH REALITY THEORY SKILLS. The importance of an effective quality counselor is the whole person of the counselor. This is indicated by the ability of the counselor's performance through the approach or theory of guidance and counseling. It aims to improve the quality of the counselor's performance through the reality therapy that can bring the full direction of the counselor's personality. Reality therapy directs the counselor's personality to be responsibility, honest (reality), sincere (right) to facilitate counselors in conducting guidance and counseling services. The embodiment of this is carried out through community service activities. The method of activity used is an online workshop (webinar) with steps, the first is the initial step (observation), the planning stage, the socialization stage, and the ongoing evaluation stage of the program. The community service activities were attended by 255 participants. The results obtained in community service activities are that 55% have clear abilities, 43% have sufficient abilities, and 2% have less abilities. Thus, the form of contribution to the science of guidance and counseling and education is expected to be implemented (reality therapy) together with stakeholders in order to achieve optimal and comprehensive success