Including the workload effect in the parallel program signature

Performance prediction and application behavior modeling have been the subject of exten- sive research that aim to estimate applications performance with an acceptable precision. A novel approach to predict the performance of parallel applications is based in the con- cept of Parallel Application Signatures that consists in extract an application most relevant parts (phases) and the number of times they repeat (weights). Executing these phases in a target machine and multiplying its exeuction time by its weight an estimation of the application total execution time can be made. One of the problems is that the performance of an application depends on the program workload. Every type of workload affects differently how an application performs in a given system and so affects the signature execution time. Since the workloads used in most scientific parallel applications have dimensions and data ranges well known and the behavior of these applications are mostly deterministic, a model of how the programs workload affect its performance can be obtained. We create a new methodology to model how a program’s workload affect the parallel application signature. Using regression analysis we are able to generalize each phase time execution and weight function to predict an application performance in a target system for any type of workload within predefined range. We validate our methodology using a synthetic program, benchmarks applications and well known real scientific applications.

Open workload scheduler

Producte de planificació de treballs batch multiplataforma basat en sistemes GNU/Linux.

Who benefits from parental leave in Spain? : a life course analysis

This paper analyses the extent to which individual and workplacecharacteristics and regional policies influence the use and duration ofparental leave in Spain. The research is based on a sample of 125,165people, and 6,959 parental leaves stemming from the ‘Sample ofWorking Life Histories’ (SWLH), 2006. The SWLH consists of administrative register data which include information from threedifferent sources: Social Security, Municipality and Income TaxRegisters. We adopt a simultaneous equations approach to analyse theuse (logistic regression) and duration (event history analysis) ofparental leave, which allows us to control for endogeneity and censoredobservations. We argue that the Spanish parental leave scheme increases gender and social inequalities insofar as reinforces genderrole specialization, and only encourages the reconciling of work andfamily life among workers with a good position in the labour market(educated employees with high and stable working status).

Where do I leave my baby? use and development of early childcare in Spain

Since the beginning of the 1990s, there has been a setady increase in childcare coverage for children aged 0-3 in Spain. The coverage has rised from 4 per cent in 1992 to 13.5 in 2004. Despite this positive trend, the supply of childcare services for under-3 is among the lowest in Western European countries.

Why do workers leave unions? - group differences in a Spanish Union Federation

This study analyses the characteristics of members leaving a Spanishunion federation – Catalonia branch of Workers’ Commissions(CCOO-Catalonia), together with their reasons for leaving using avariety of data sources. Our findings indicate that higher union attritionamong members in instable employment (i.e. casual employment andlow seniority). In general, union leavers confirm that their job situationis an important reason for leaving the union. We therefore concludethat efforts made by the union to retain members in vulnerable labormarket positions are important in reducing high rates of union attritionin Spain.

The Social Politics of Fatherhood in Spain and France: a Comparative Analysis of Parental Leave and Shared Residence

The Social Politics of Fatherhood in Spain and France: A Comparative Analysis of Parental Leave and Shared Residence The article provides a comparative analysis of policy developments on leaves for fathers and joint custody in Spain and France in the last decade. These two types of measures have been selected because they are both widely recognised as main instruments to promote new fathering styles and consequently more gender equality in the European Union. While the rhetoric of choice has been developed in both countries in relation to maternal employment and childcare, with better results in France than in Spain, it remains to be seen to what extent choice will also be extended to fathers. Keywords: Fatherhood. Family. Comparative social policy. Parental leave. Joint custody.

The Social Politics of Fatherhood in Spain and France: a Comparative Analysis of Parental Leave and Shared Residence

The Social Politics of Fatherhood in Spain and France: A Comparative Analysis of Parental Leave and Shared Residence The article provides a comparative analysis of policy developments on leaves for fathers and joint custody in Spain and France in the last decade. These two types of measures have been selected because they are both widely recognised as main instruments to promote new fathering styles and consequently more gender equality in the European Union. While the rhetoric of choice has been developed in both countries in relation to maternal employment and childcare, with better results in France than in Spain, it remains to be seen to what extent choice will also be extended to fathers. Keywords: Fatherhood. Family. Comparative social policy. Parental leave. Joint custody.

Dynamic matching and bargaining: the role of deadlines

We consider a dynamic model where traders in each period are matched randomly into pairs who then bargain about the division of a fixed surplus. When agreement is reached the traders leave the market. Traders who do not come to an agreement return next period in which they will be matched again, as long as their deadline has not expired yet. New traders enter exogenously in each period. We assume that traders within a pair know each other's deadline. We define and characterize the stationary equilibrium configurations. Traders with longer deadlines fare better than traders with short deadlines. It is shown that the heterogeneity of deadlines may cause delay. It is then shown that a centralized mechanism that controls the matching protocol, but does not interfere with the bargaining, eliminates all delay. Even though this efficient centralized mechanism is not as good for traders with long deadlines, it is shown that in a model where all traders can choose which mechanism to

Voting by committees with exit

We study the problem of a society choosing a subset of new members from a finite set of candidates (as in Barberà, Sonnenschein, and Zhou, 1991). However, we explicitly consider the possibility that initial members of the society (founders) may want to leave it if they do not like the resulting new society. We show that, if founders have separable (or additive) preferences, the unique strategy-proof and stable social choice function satisfying voters' sovereignty (on the set of candidates) is the one where candidates are chosen unanimously and no founder leaves the society.

Inequity version and team incentives

We study optimal contracts in a simple model where employees are averse to inequity as modelled by Fehr and Schmidt (1999). A "selfish" employer can profitably exploit such preferences among its employees by offering contracts which create inequity off-equilibrium and thus, they would leave employees feeling envy or guilt when they do not meet the employer's demands. Such contracts resemble team and relative performance contracts, and thus we derive conditions under which it may be beneficial to form work teams of employees with distributional concerns who were previously working individually. Similar results are obtained for status-seeking and efficiency concerns preferences.

Pareto-improving optimal capital and labor taxes

We show a standard model where the optimal tax reform is to cut labor taxes and leave capital taxes very high in the short and medium run. Only in the very long run would capital taxes be zero. Our model is a version of Chamley??s, with heterogeneous agents, without lump sum transfers, an upper bound on capital taxes, and a focus on Pareto improving plans. For our calibration labor taxes should be low for the first ten to twenty years, while capital taxes should be at their maximum. This policy ensures that all agents benefit from the tax reform and that capital grows quickly after when the reform begins. Therefore, the long run optimal tax mix is the opposite from the short and medium run tax mix. The initial labor tax cut is financed by deficits that lead to a positive long run level of government debt, reversing the standard prediction that government accumulates savings in models with optimal capital taxes. If labor supply is somewhat elastic benefits from tax reform are high and they can be shifted entirely to capitalists or workers by varying the length of the transition. With inelastic labor supply there is an increasing part of the equilibrium frontier, this means that the scope for benefitting the workers is limited and the total benefits from reforming taxes are much lower.

Wealth constraints, skill prices or networks: what determines emigrant selection?

The productive characteristics of migrating individuals, emigrant selection, affect welfare. The empirical estimation of the degree of selection suffers from a lack of complete and nationally representative data. This paper uses a new and better dataset to address both issues: the ENET (Mexican Labor Survey), which identifies emigrants right before they leave and allows a direct comparison to non-migrants. This dataset presents a relevant dichotomy: it shows on average negative selection for Mexican emigrants to the United States for the period 2000-2004 together with positive selection in Mexican emigration out of rural Mexico to the United States in the same period. Three theories that could explain this dichotomy are tested. Whereas higher skill prices in Mexico than in the US are enough to explain negative selection in urban Mexico, its combination with network effects and wealth constraints is required to account for positive selection in rural Mexico.

New evidence on emigrant selection

This paper examines the extent to which Mexican emigrants to the United States are negatively selected, that is, have lower skills than individuals who remain in Mexico. Previous studies have been limited by the lack of nationally representative longitudinal data. This one uses a newly available household survey, which identifies emigrants before they leave and allows a direct comparison to non-migrants. I find that, on average, US bound Mexican emigrants from 2000 to 2004 earn a lower wage and have less schooling years than individuals who remain in Mexico, evidence of negative selection. This supports the original hypothesis of Borjas (AER, 1987) and argues against recent findings, notably those of Chiquiar and Hanson (JPE, 2005). The discrepancy with the latter is primarily due to an under-count of unskilled migrants in US sources and secondarily to the omission of unobservables in their methodology.

Inverse problems for invariant algebraic curves: explicit computations

Given an algebraic curve in the complex affine plane, we describe how to determine all planar polynomial vector fields which leave this curve invariant. If all (finite) singular points of the curve are nondegenerate, we give an explicit expression for these vector fields. In the general setting we provide an algorithmic approach, and as an alternative we discuss sigma processes.

Coupling and monotonicity of queueing processes

The main purpose of this work is to give a survey of main monotonicity properties of queueing processes based on the coupling method. The literature on this topic is quite extensive, and we do not consider all aspects of this topic. Our more concrete goal is to select the most interesting basic monotonicity results and give simple and elegant proofs. Also we give a few new (or revised) proofs of a few important monotonicity properties for the queue-size and workload processes both in single-server and multi- server systems. The paper is organized as follows. In Section 1, the basic notions and results on coupling method are given. Section 2 contains known coupling results for renewal processes with focus on construction of synchronized renewal instants for a superposition of independent renewal processes. In Section 3, we present basic monotonicity results for the queue-size and workload processes. We consider both discrete-and continuous-time queueing systems with single and multi servers. Less known results on monotonicity of queueing processes with dependent service times and interarrival times are also presented. Section 4 is devoted to monotonicity of general Jackson-type queueing networks with Markovian routing. This section is based on the notable paper [17]. Finally, Section 5 contains elements of stability analysis of regenerative queues and networks, where coupling and monotonicity results play a crucial role to establish minimal suficient stability conditions. Besides, we present some new monotonicity results for tandem networks.