Labor Migration and Social Networks Participation: Evidence from Southern Mozambique

This paper investigates how social networks in poor developing settings are af- fected if people migrate. By using an unique household survey from two southern regions in Mozambique, we test the role of labor mobility in shaping participation in groups and social networks by migrant sending households in village economies at origin. We find that households with successful migrants (i.e. those receiving either remittances or return migration) engage more in community based social networks. Our findings are robust to alternative definitions of social interaction and to endogeneity concerns suggesting that stable migration ties and higher income stability through remittances may decrease participation constraints and increase household commitment in cooperative arrangements in migrant-sending communities.International Migration, Social Capital, Networks, Group Participation, Mozambique

Pseudospectral versus finite-differences schemes in the numerical integration of stochastic models of surface growth

We present a comparison between finite differences schemes and a pseudospectral method applied to the numerical integration of stochastic partial differential equations that model surface growth. We have studied, in 1+1 dimensions, the Kardar, Parisi and Zhang model (KPZ) and the Lai, Das Sarma and Villain model (LDV). The pseudospectral method appears to be the most stable for a given time step for both models. This means that the time up to which we can follow the temporal evolution of a given system is larger for the pseudospectral method. Moreover, for the KPZ model, a pseudospectral scheme gives results closer to the predictions of the continuum model than those obtained through finite difference methods. On the other hand, some numerical instabilities appearing with finite difference methods for the LDV model are absent when a pseudospectral integration is performed. These numerical instabilities give rise to an approximate multiscaling observed in the numerical simulations. With the pseudospectral approach no multiscaling is seen in agreement with the continuum model.Comment: 13 single column pages, RevTeX, 6 eps fig

Scaling of Local Slopes, Conservation Laws and Anomalous Roughening in Surface Growth

We argue that symmetries and conservation laws greatly restrict the form of the terms entering the long wavelength description of growth models exhibiting anomalous roughening. This is exploited to show by dynamic renormalization group arguments that intrinsic anomalous roughening cannot occur in local growth models. However some conserved dynamics may display super-roughening if a given type of terms are present.Comment: To appear in Phys. Rev. Lett., 4 pages in RevTeX style, no fig

Works Councils: An Agency Perspective

This paper investigates the role of works councils in a simple agency framework in whichworks councils are supposed to monitor manager's information on behalf of the workforce,but they are independent agents who might pursue their private interest. First, we considerthat workers can incentivize works councils through contingent monetary payments. In orderto deter collusion, workers must pay higher compensations in states of nature where they canbe expropriated by potential coalitions among works councils and management. Collusionmakes contingent payments costly and reduces workers' payoffs. Second, when elections areused to align works councils' interest only well compensated representatives would face aninter-temporal trade-off between accepting management's transfers at first period and losingrents at the second period. Elections increase the cost of entering on collusive behaviour withmanagement and works councils will try to behave on the employees' interest

Open Source High Fidelity Modeling of a Type 5 Wind Turbine Drivetrain for Grid Integration

The increasing integration of renewable energy resources in evolving bulk power system (BPS) is impacting the system inertia. Type-5 wind turbine generation has the potential to behave like a traditional synchronous generator and can help improve system inertia. Hydraulic torque converter (TC) and gearbox with torque limiting feature are integral parts of a Type-5 wind turbine unit. High fidelity model of Type-5 wind turbine including these core components is not openly and widely available for grid integration and transient stability studies. This hinders appropriate assessment of Type-5 wind power plant's contribution to bulk grid resilience. This work develops a TC model based on those generally used in automobile's transmission system. Moreover, the concept of torsional coupling is leveraged to integrate the TC and gearbox system dynamics. The entire integrated model will be open sourced and publicly available for grid integration studies.Comment: This manuscript is originally submitted to Journal of Physic

Catálogo actualizado de los briófitos de la Región de Murcia (Sureste de España)

An updated checklist of the bryophytes of the Region of Murcia is provided. Bryophyte diversity in Murcia consists of 200 especies and 15 infraespecific taxa (77 genera) of mosses and 32 species (20 genera) of liverworts. Grimmia tergestina is confirmed in the territory. Aschisma cuynetii, Brachytheciastrum dieckii, Brachythecium albicans, Brachythecium rutabulum, Brachythecium salebrosum, Bryum alpinum, Bryum elegans, Campyliadelphus chrysophyllus, Campylopus pilifer and Didymodon eckeliae are new reported for Murcia. Bryum tenuisetum, Entosthodon attenuatus and Fissidens bryoides are excluded from the check-list.Se actualiza el catálogo de los briófitos de la Región de Murcia. Para este territorio se aceptan 200 especies y 15 taxones infraespecíficos (77 géneros) de musgos y 32 especies de hepáticas (20 géneros). Grimmia tergestina se confirma en el territorio. Aschisma cuynetii, Brachytheciastrum dieckii, Brachythecium albicans, Brachythecium rutabulum, Brachythecium salebrosum, Bryum alpinum, Bryum elegans, Campyliadelphus chrysophyllus, Campylopus pilifer y Didymodon eckeliae son nuevas citas para Murcia. Bryum tenuisetum, Entosthodon attenuatus y Fissidens bryoides se excluyen del catálogo

Identifying Student Profiles Within Online Judge Systems Using Explainable Artificial Intelligence

Online Judge (OJ) systems are typically considered within programming-related courses as they yield fast and objective assessments of the code developed by the students. Such an evaluation generally provides a single decision based on a rubric, most commonly whether the submission successfully accomplished the assignment. Nevertheless, since in an educational context such information may be deemed insufficient, it would be beneficial for both the student and the instructor to receive additional feedback about the overall development of the task. This work aims to tackle this limitation by considering the further exploitation of the information gathered by the OJ and automatically inferring feedback for both the student and the instructor. More precisely, we consider the use of learning-based schemes—particularly, Multi-Instance Learning and classical Machine Learning formulations—to model student behaviour. Besides, Explainable Artificial Intelligence is contemplated to provide human-understandable feedback. The proposal has been evaluated considering a case of study comprising 2,500 submissions from roughly 90 different students from a programming-related course in a Computer Science degree. The results obtained validate the proposal: the model is capable of significantly predicting the user outcome (either passing or failing the assignment) solely based on the behavioural pattern inferred by the submissions provided to the OJ. Moreover, the proposal is able to identify prone-to-fail student groups and profiles as well as other relevant information, which eventually serves as feedback to both the student and the instructor.This work has been partially funded by the “Programa Redes-I3CE de investigacion en docencia universitaria del Instituto de Ciencias de la Educacion (REDES-I3CE-2020-5069)” of the University of Alicante. The third author is supported by grant APOSTD/2020/256 from “Programa I+D+I de la Generalitat Valenciana”