392 research outputs found
INTERNATIONAL TRANSMISSION OF MONETARY SHOCKS WITH INTEREST RATE RULE
This paper explores the implications of monetary policy rules in the general equilibrium two-country framework of Obstfeld and Rogo (1995). It is argued that the sign of the correlation of domestic and foreign outputs can be positive after a monetary shock, contrary to the standard result. The reason is that an interest rate rule targeting the consumer price index implies less volatile terms of trade and this reduces the expenditure switching e€ect, and thus the demand e€ect through the fall of the real interest rate prevails. It is also shown that inertia in the interest rate rule is a necessary condition for the model to display persistence of the real variables after a shock to the interest rate rule.Monetary Policy Rules, International Transmission, Staggered Prices, Two-Country model
Using reservoir computing to construct scarred wavefunctions
Scar theory is one of the fundamental pillars in the field of quantum chaos,
and scarred functions a superb tool to carry out studies in it. Several
methods, usually semiclassical, have been described to cope with these two
phenomena. In this paper, we present an alternative method, based on the novel
machine learning algorithm known as Reservoir Computing, to calculate such
scarred wavefunctions together with the associated eigenstates of the system.
The resulting methodology achieves outstanding accuracy while reducing
execution times by a factor of ten. As an illustration of the effectiveness of
this method, we apply it to the widespread chaotic two-dimensional coupled
quartic oscillator.Comment: arXiv admin note: text overlap with arXiv:2310.0745
Towards AC-induced optimum control of dynamical localization
It is shown that optimum control of dynamical localization (quantum
suppression of classical diffusion) in the context of ultracold atoms in
periodically shaken optical lattices subjected to time-periodic forces having
equidistant zeros depends on the \textit{impulse} transmitted by the external
force over half-period rather than on the force amplitude. This result provides
a useful principle for optimally controlling dynamical localization in general
periodic systems, which is capable of experimental realization.Comment: 7 pages, 6 figure
Wage Assimilation of Immigrants in Spain
In this study we quantify the effect of the years of residence in Spain on the earnings of immigrants. We take sex, origin, education and age into account. The results are clearly positive, the longer the length of residence the more earnings, confirming the hypothesis of wage assimilation of immigrants as their human capital is adapted to the Spanish labor market. The information used comes from the Social Securityâs Continuous Sample of Working Lives 2007. Additionally, we merge the earnings data from this source with the National Survey of Immigrants 2007 to obtain additional integration indicators, such as speaking fluently Spanish, validation of studies in Spain, studies finished in Spain. All of them increase the earnings of immigrants. We detail this results by sex and origin (Europe, Latin-America and Rest of the World).immigration, wage assimilation, wages, human capital, merging of databases
Short periodic orbits theory for partially open quantum maps
We extend the semiclassical theory of short periodic orbits [Phys. Rev. E
{\bf 80}, 035202(R) (2009)] to partially open quantum maps. They correspond to
classical maps where the trajectories are partially bounced back due to a
finite reflectivity . These maps are representative of a class that has many
experimental applications. The open scar functions are conveniently redefined,
providing a suitable tool for the investigation of these kind of systems. Our
theory is applied to the paradigmatic partially open tribaker map. We find that
the set of periodic orbits that belong to the classical repeller of the open
map () are able to support the set of long-lived resonances of the
partially open quantum map in a perturbative regime. By including the most
relevant trajectories outside of this set, the validity of the approximation is
extended to a broad range of values. Finally, we identify the details of
the transition from qualitatively open to qualitatively closed behaviour,
providing an explanation in terms of short periodic orbits.Comment: 6 pages, 4 figure
Anticipating food price crises by reservoir computing
Anticipating price crises in the market of agri-commodities is critical to guarantee both the sustainability of the food system and to ensure food security. However, this is not an easy task, since the problem implies analyzing small and very volatile time series, which are highly influenced by external factors. In this paper, we show that suitable reservoir computing algorithms can be developed that outperform traditional approaches, by reducing the Mean Absolute Error and, more importantly, increasing the Market Direction Accuracy. For this purpose, the applicability of five variants of such method to forecast this market is explored, and their performance evaluated by comparing the results with those obtained with the standard LSTM and SARIMA benchmarks. We conclude that decomposing the time series and modeling each component with a separate RC is essential to successfully anticipate price trends, and that this method works even in the complex changing temporal scenario of the Covid-19 pandemic, when part of the data were collectedThe project that gave rise to these results received the support of a fellowship from ââla Caixaââ Foundation (ID 100010434). The fellowship code is LCF/BQ/DR20/11790028. This work has also been partially supported by the Spanish Ministry of Science, Innovation and Universities, Gobierno de España, under Contract No. PID2021-122711NB-C21; and by DG of Research and Technological Innovation of the Community of Madrid (Spain) under Contract No. IND2022/TIC-2371
To each according to its degree: The meritocracy and topocracy of embedded markets
A system is said to be meritocratic if the compensation and power available to individuals is determined by
their abilities and merits. A system is topocratic if the compensation and power available to an individual is
determined primarily by her position in a network. Here we introduce a model that is perfectly meritocratic
for fully connected networks but that becomes topocratic for sparse networks-like the ones in society. In the
model, individuals produce and sell content, but also distribute the content produced by others when they
belong to the shortest path connecting a buyer and a seller. The production and distribution of content
defines two channels of compensation: a meritocratic channel, where individuals are compensated for the
content they produce, and a topocratic channel, where individual compensation is based on the number of
shortest paths that go through them in the network. We solve the model analytically and show that the
distribution of payoffs is meritocratic only if the average degree of the nodes is larger than a root of the total
number of nodes. We conclude that, in the light of this model, the sparsity and structure of networks
represents a fundamental constraint to the meritocracy of societiesSupport from the MIT Media Lab Consortia, FundaciĂłn Caja Madrid (Spain),
UAM-Santander (Spain) and CONICYT grants: Anillo en Complejidad Social SOC-1101
and Fondecyt 1110351 is gratefully acknowledge
To Each According to its Degree: The Meritocracy and Topocracy of Embedded Markets
A system is said to be meritocratic if the compensation and power available to individuals is determined by their abilities and merits. A system is topocratic if the compensation and power available to an individual is determined primarily by her position in a network. Here we introduce a model that is perfectly meritocratic for fully connected networks but that becomes topocratic for sparse networks-like the ones in society. In the model, individuals produce and sell content, but also distribute the content produced by others when they belong to the shortest path connecting a buyer and a seller. The production and distribution of content defines two channels of compensation: a meritocratic channel, where individuals are compensated for the content they produce, and a topocratic channel, where individual compensation is based on the number of shortest paths that go through them in the network. We solve the model analytically and show that the distribution of payoffs is meritocratic only if the average degree of the nodes is larger than a root of the total number of nodes. We conclude that, in the light of this model, the sparsity and structure of networks represents a fundamental constraint to the meritocracy of societies.MIT Media Lab Consortiu
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