Javier Perez - Profile on Academia.edu (original) (raw)

Papers by Javier Perez

This paper presents an optimal fiscal policy response to address the basic tradeo between the aut... more This paper presents an optimal fiscal policy response to address the basic tradeo between the automatic stabilisation properties of budgets and the long run fiscal positions. The framework is an overlapping generations model à la , extended to account for stochastic endowments and borrowing constrained households. A benign government chooses over the optimal degree of responsiveness of net taxes to individual incomes, an optimal measure of long-run public debt, or both, in order to smooth households' consumption across states of nature. In the presence of a deficit constraint for the government, the results unambiguously point to the desire for lower debt levels than those currently prevailing in order to enable a more e ective hedging of personal income uncertainty by means of more active fiscal stabilisers. Citizens in economies exhibiting more pronounced cycles will favour less automatic stabilisation combined with a more aggressive policy of debt reduction.

SSRN Electronic Journal, 2015

Should rational agents take into consideration government policy announcements? A skilled agent (... more Should rational agents take into consideration government policy announcements? A skilled agent (an econometrician) could set up a model to combine the following two pieces of information in order to anticipate the future course of fiscal policy in real-time: (i) the ex-ante path of policy as published/announced by the government; (ii) incoming, observed data on the actual degree of implementation of ongoing plans. We formulate and estimate empirical models for a number of EU countries (Germany, France, Italy, and Spain) to show that government (consumption) targets convey useful information about ex-post policy developments when policy changes significantly (even if past credibility is low) and when there is limited information about the implementation of plans (e.g. at the beginning of a fiscal year). In addition, our models are instrumental to unveil the current course of policy in real-time. Our approach complements a well-established branch of the literature that finds politicallymotivated biases in policy targets.

Computation of refactoring plans from refactoring strategies using HTN planning

Proceedings of the Fifth Workshop on Refactoring Tools - WRT '12, 2012

Complex refactoring processes, such as applying big refactorings or removing design smells are di... more Complex refactoring processes, such as applying big refactorings or removing design smells are difficult to perform in practice. The complexity of these processes is partly due to their heuristic nature and to the constraints imposed by preconditions on the applicability of the individual refactorings. We introduce refactoring strategies as heuristic-based, automation-suitable specifications of a complex refactoring process. They allow us to specify correction strategies and big refactorings more formally than it is done in current catalogues. Refactoring strategies can be instantiated, for each particular case, into refactoring plans. We define refactoring plans as sequences of refactorings that are immediately applicable over the current system source code. We have developed an approach for instantiating refactoring strategies into refactoring plans that uses Hierarchical Task Network (HTN) planning. This paper describes this approach and presents a case study, in order to evaluate and characterise it.

P03-61 - Antipsychotic injectable treatment in patients with involuntary ambulatory treatment

European Psychiatry, 2011

IntroductionInvoluntary Ambulatory Treatment (IAT) is a judicial measure existing in Spain. Its a... more IntroductionInvoluntary Ambulatory Treatment (IAT) is a judicial measure existing in Spain. Its aim is to ensure the adherence to treatment of seriously ill patients, with poor insight and repeated hospitalization. This is done by means of the regular and involuntary administration of antipsychotic intramuscular medication.ObjectivesTo assess the treatment used in patients undergoing IAT in a local clinic, to assess the type of medicaments and their dosage and to verify adherence to treatment and evolution.Material and methodA revision was made of the clinical backgrounds of all the patients of a psychiatric outpatient clinic who have been submitted to IAT (n = 37). A note was made of socio-demographic variables as well as psychiatric diagnoses according to DSM-IV-TR criteria and the number of hospitalizations and treatments used.ResultsAll but one patient had been hospitalized and average of 3.53 times before IAT. Since undergoing IAT only 6 patients have been admitted (16%). Four ...

SAXS Conformational Tracking of Amylose Synthesized by Amylosucrases

Biomacromolecules, 2013

Amylose, a linear polymer of α(1,4)-linked glucosyl units and a major constituent of starch granu... more Amylose, a linear polymer of α(1,4)-linked glucosyl units and a major constituent of starch granules, can also be enzymatically synthesized in vitro from sucrose by bacterial amylosucrases. Depending on the initial sucrose concentration and the enzyme used, amylose oligomers (or polymers) are formed and self-associate during synthesis into various semicrystalline morphologies. This work describes for the first time a synchrotron SAXS study of the structure in solution of two amylosucrases, namely, NpAS and the thermostable DgAS, under conditions of polymer synthesis and, simultaneously, the amylose conformation. The structure in solution of both amylosucrases during the reaction was shown to be similar to the known crystallographic structures. The conformation of amylose produced at an early stage consists of a mixture of wormlike chains and double helical cylindrical structures. In the case of NpAS, in a second stage, individual double helices pack into clusters before crystallizing and precipitating. Amylose produced by DgAS never self-associates in such clusters due to the higher temperature used for amylose synthesis. All the dimensions determined for wormlike chains and cylindrical conformations at different times of NpAS synthesis are in very good agreement with structural features usually observed on gels of amylose extracted from starch. This provides new insights in understanding the mechanisms of amylose gelation.

This paper presents an optimal fiscal policy response to address the basic tradeo between the aut... more This paper presents an optimal fiscal policy response to address the basic tradeo between the automatic stabilisation properties of budgets and the long run fiscal positions. The framework is an overlapping generations model à la , extended to account for stochastic endowments and borrowing constrained households. A benign government chooses over the optimal degree of responsiveness of net taxes to individual incomes, an optimal measure of long-run public debt, or both, in order to smooth households' consumption across states of nature. In the presence of a deficit constraint for the government, the results unambiguously point to the desire for lower debt levels than those currently prevailing in order to enable a more e ective hedging of personal income uncertainty by means of more active fiscal stabilisers. Citizens in economies exhibiting more pronounced cycles will favour less automatic stabilisation combined with a more aggressive policy of debt reduction.

SSRN Electronic Journal, 2015

Should rational agents take into consideration government policy announcements? A skilled agent (... more Should rational agents take into consideration government policy announcements? A skilled agent (an econometrician) could set up a model to combine the following two pieces of information in order to anticipate the future course of fiscal policy in real-time: (i) the ex-ante path of policy as published/announced by the government; (ii) incoming, observed data on the actual degree of implementation of ongoing plans. We formulate and estimate empirical models for a number of EU countries (Germany, France, Italy, and Spain) to show that government (consumption) targets convey useful information about ex-post policy developments when policy changes significantly (even if past credibility is low) and when there is limited information about the implementation of plans (e.g. at the beginning of a fiscal year). In addition, our models are instrumental to unveil the current course of policy in real-time. Our approach complements a well-established branch of the literature that finds politicallymotivated biases in policy targets.

Computation of refactoring plans from refactoring strategies using HTN planning

Proceedings of the Fifth Workshop on Refactoring Tools - WRT '12, 2012

Complex refactoring processes, such as applying big refactorings or removing design smells are di... more Complex refactoring processes, such as applying big refactorings or removing design smells are difficult to perform in practice. The complexity of these processes is partly due to their heuristic nature and to the constraints imposed by preconditions on the applicability of the individual refactorings. We introduce refactoring strategies as heuristic-based, automation-suitable specifications of a complex refactoring process. They allow us to specify correction strategies and big refactorings more formally than it is done in current catalogues. Refactoring strategies can be instantiated, for each particular case, into refactoring plans. We define refactoring plans as sequences of refactorings that are immediately applicable over the current system source code. We have developed an approach for instantiating refactoring strategies into refactoring plans that uses Hierarchical Task Network (HTN) planning. This paper describes this approach and presents a case study, in order to evaluate and characterise it.

P03-61 - Antipsychotic injectable treatment in patients with involuntary ambulatory treatment

European Psychiatry, 2011

IntroductionInvoluntary Ambulatory Treatment (IAT) is a judicial measure existing in Spain. Its a... more IntroductionInvoluntary Ambulatory Treatment (IAT) is a judicial measure existing in Spain. Its aim is to ensure the adherence to treatment of seriously ill patients, with poor insight and repeated hospitalization. This is done by means of the regular and involuntary administration of antipsychotic intramuscular medication.ObjectivesTo assess the treatment used in patients undergoing IAT in a local clinic, to assess the type of medicaments and their dosage and to verify adherence to treatment and evolution.Material and methodA revision was made of the clinical backgrounds of all the patients of a psychiatric outpatient clinic who have been submitted to IAT (n = 37). A note was made of socio-demographic variables as well as psychiatric diagnoses according to DSM-IV-TR criteria and the number of hospitalizations and treatments used.ResultsAll but one patient had been hospitalized and average of 3.53 times before IAT. Since undergoing IAT only 6 patients have been admitted (16%). Four ...

SAXS Conformational Tracking of Amylose Synthesized by Amylosucrases

Biomacromolecules, 2013

Amylose, a linear polymer of α(1,4)-linked glucosyl units and a major constituent of starch granu... more Amylose, a linear polymer of α(1,4)-linked glucosyl units and a major constituent of starch granules, can also be enzymatically synthesized in vitro from sucrose by bacterial amylosucrases. Depending on the initial sucrose concentration and the enzyme used, amylose oligomers (or polymers) are formed and self-associate during synthesis into various semicrystalline morphologies. This work describes for the first time a synchrotron SAXS study of the structure in solution of two amylosucrases, namely, NpAS and the thermostable DgAS, under conditions of polymer synthesis and, simultaneously, the amylose conformation. The structure in solution of both amylosucrases during the reaction was shown to be similar to the known crystallographic structures. The conformation of amylose produced at an early stage consists of a mixture of wormlike chains and double helical cylindrical structures. In the case of NpAS, in a second stage, individual double helices pack into clusters before crystallizing and precipitating. Amylose produced by DgAS never self-associates in such clusters due to the higher temperature used for amylose synthesis. All the dimensions determined for wormlike chains and cylindrical conformations at different times of NpAS synthesis are in very good agreement with structural features usually observed on gels of amylose extracted from starch. This provides new insights in understanding the mechanisms of amylose gelation.