Skilled migration and innovation in European industries

This paper studies the effects of skilled migration on innovation –proxied by patent citations- in European industries between 1994 and 2005, using the French and the UK Labour Force Surveys and the German Microcensus. Highly-educated migrants have a positive effect on innovation, but the effect differs across industries. It is stronger in industries with low levels of overeducation, high levels of FDIs and openness to trade and, finally, in industries with higher ethnic diversity. The aggregate effect of the skilled immigrant is about one third the one of the skilled natives. We tackle the endogeneity of migrants with a set of external and internal instruments.     

The association between financial aid availability and the college dropout rates in Colombia

The main objective of this study is to estimate the association between financial aid and college dropout rates of postsecondary students in Colombia. We use a unique dataset from the Colombian Ministry of Education that includes all enrolled college students in the country between 1998 and 2008. Logistic regression is used to identify the correlation between receiving different forms of financial aid on the dropout rates of the students. The main results of the study suggest that the probability of dropping out decrease between 25 and 29% according to the type of financial aid received. There is also evidence that the financial aid is more effective in reducing dropout rates at the beginning of the student’s college careers. This result holds after controlling by type of postsecondary institution attended. These findings suggest that financial aid is an effective tool to reduce dropout rates, and therefore increase persistence and expand access in Colombia.     

Dribbling speed along curved paths predicts attacking performance in match-realistic one vs. one soccer games

This study assessed whether a new, closed-skill dribbling or sprinting task could predict attacking performance in soccer. Twenty-five male players were recruited from the Londrina Junior Team Football Academy in Brazil and asked to either dribble the ball or sprint through five custom circuits that varied in average curvature (0–1.37 radians.m^?1). These measures were then validated using a realistic one vs. one competition in which each player acted as attacker or defender in turn (N = 1330 bouts). Sprinting (ICC = 0.96) and dribbling (ICC = 0.97) performances were highly repeatable for individual players. Average dribbling speed decreased non-linearly with increasing circuit curvature (F = 239.5; P < 0.001) from 5.19 ± 0.11 ms^?1 on the straightest path to 2.13 ± 0.03 ms^?1 on the curviest. Overall, dribbling but not sprinting performance predicted attacking success in the one vs. one competition, explaining more than 50% of the variation in attacking success alone (r_p = 0.70; P < 0.001). In conclusion, our new closed-skill dribbling assessment is a valid and reliable protocol to predict a soccer player’s success in attacking performance in one vs. one situation, and can be used to identify talented players.     

Vascular architecture:is it a helpful histopathological biomarker for hepatocellular carcinoma?

Hepatocellular carcinoma(HCC) remains one of the major public health problems throughout the world.Although originally associated with tumorigenic processes,liver angiogenesis has also been observed in the context of different liver in-flammatory,fibrotic,and ischemic conditions.Here we investigate the fractal dimension as a quantitator of non-Euclidean two-dimensional vascular geometry in a series of paired specimens of primary HCC and surrounding non-tumoral tissue,and discuss why this parameter might provide additional information regarding cancer behavior.The application of fractal geometry to the measurement of liver vascularity and the availability of a computer-aided quantitative method can eliminate errors in visual interpretation,and make it possible to obtain closer-to-reality numerals that are compulsory for any measurement process.     

Linguistic aggregation methods in blog retrieval

This paper addresses the blog distillation problem, that is, given a user query find the blogs that are most related to the query topic. We model each post as evidence of the relevance of a blog to the query, and use aggregation methods like Ordered Weighted Averaging (OWA) operators to combine the evidence. We show that using only highly relevant evidence (posts) for each blog can result in an effective retrieval system. We also take into account the importance of the posts in a query-based cluster and investigate its effect in the aggregation results. We use prioritized OWA operators and show that considering the importance is effective when the number of aggregated posts from each blog is high. We carry out our experiments on three different data sets (TREC07, TREC08 and TREC09) and show statistically significant improvements over state of the art model called voting model.     

Does soccer cleat design influence the rotational interaction with the playing surface?

Non-contact injuries in soccer players may be related to the interplay between cleat type and playing surface, and bladed shoes were often blamed for non-contact injuries with no research support. The aim of this study was to compare the rotational resistance (stiffness and peak sustainable torque) among three types of soccer cleats (metal studs, molded rubber studs, and bladed) in a controlled laboratory environment. The shoes were tested on both natural and artificial turfs under a compressive preload of 1000 N and with internal and external rotations. The three shoe models showed comparable performances with a good repeatability for each individual test on both playing surfaces. A less stiff behavior was observed for the natural turf. A tendency toward highest peak torque was observed in the studded model on natural surface. The bladed cleats provided peak torque and rotational stiffness comparable to the other models. Studded and bladed cleats did not significantly differ in their interaction with the playing surface. Therefore, soccer shoes with bladed cleats should not be banned in the context of presumed higher risk for non-contact injuries.     

A multi-collection latent topic model for federated search

Collection selection is a crucial function, central to the effectiveness and efficiency of a federated information retrieval system. A variety of solutions have been proposed for collection selection adapting proven techniques used in centralised retrieval. This paper defines a new approach to collection selection that models the topical distribution in each collection. We describe an extended version of latent Dirichlet allocation that uses a hierarchical hyperprior to enable the different topical distributions found in each collection to be modelled. Under the model, resources are ranked based on the topical relationship between query and collection. By modelling collections in a low dimensional topic space, we can implicitly smooth their term-based characterisation with appropriate terms from topically related samples, thereby dealing with the problem of missing vocabulary within the samples. An important advantage of adopting this hierarchical model over current approaches is that the model generalises well to unseen documents given small samples of each collection. The latent structure of each collection can therefore be estimated well despite imperfect information for each collection such as sampled documents obtained through query-based sampling. Experiments demonstrate that this new, fully integrated topical model is more robust than current state of the art collection selection algorithms.