Are one-sided S,s rules useful proxies for optimal pricing rules?

This article is motivated by the prominence of one-sided S,s rules in the literature and by the unrealistic strict conditions necessary for their optimality. It aims to assess whether one-sided pricing rules could be an adequate individual rule for macroeconomic models, despite its suboptimality. It aims to answer two questions. First, since agents are not fully rational, is it plausible that they use such a non-optimal rule? Second, even if the agents adopt optimal rules, is the economist committing a serious mistake by assuming that agents use one-sided Ss rules? Using parameters based on real economy data, we found that since the additional cost involved in adopting the simpler rule is relatively small, it is plausible that one-sided rules are used in practice. We also found that suboptimal one-sided rules and optimal two-sided rules are in practice similar, since one of the bounds is not reached very often. We concluded that the macroeconomic effects when one-sided rules are suboptimal are similar to the results obtained under two-sided optimal rules, when they are close to each other. However, this is true only when one-sided rules are used in the context where they are not optimal.

Sequential cost-reimbursement rules

This paper studies cost-sharing rules under dynamic adverse selection. We present a typical principal-agent model with two periods, set up in Laffont and Tirole's (1986) canonical regulation environment. At first, when the contract is signed, the firm has prior uncertainty about its efficiency parameter. In the second period, the firm learns its efficiency and chooses the level of cost-reducing effort. The optimal mechanism sequentially screens the firm's types and achieves a higher level of welfare than its static counterpart. The contract is indirectly implemented by a sequence of transfers, consisting of a fixed advance payment based on the reported cost estimate, and an ex-post compensation linear in cost performance.

Optimal rules for monetary policy in Brazil

This paper presents optimal rules for monetary policy in Brazil derived from a backward looking expectation model consisting of a Keynesian IS function and an Augmented Phillips Curve (ISAS). The IS function displays'a high sensitivity of aggregate demand to the real interest rate and the Phillips Curve is accelerationist. The optimal monetary rules show low interest rate volatility with reaction coefficients lower than the ones suggested by Taylor (1993a,b). Reaction functions estimated through ADL and SUR models suggest that monetary policy has not been optimal and has aimed to product rather than inflation stabilization.

Optimal-state-dependent rules, credibility, and inflationary inertia

This paper examines the output losses caused by disinflation and the role of credibility in a model where pricing mIes are optimal and individual prices are rigid. Individual nominal rigidity is modeled as resulting from menu costs. The interaction between optimal pricing mIes and credibility is essential in determining the inflationary inertia. A continued period of high inflation generates an asymmetric distribution of price deviations, with more prices that are substantially lower than their desired leveIs than prices that are substantially higher than the optimal ones. When disinflation is not credible, inflationary inertia is engendered by this asymmetry: idiosyncratic shocks trigger more upward than downward adjustments. A perfect1y credible disinflation causes an immediate change of pricing rules which, by rendering the price deviation distribution less asymmetric, practically annihilates inflationary inertia. An implication of our model is that stabilization may be sucessful even when credibility is low, provided that it is preceded by a mechanism of price alignment. We also develop an analytical framework for analyzing imperfect credibility cases.

Welfare and growth effects of alternative fiscal rules for infrastructure investment in Brazil

This article studies the interplay between fiscal rules, public investment and growth in Brazil. It is investigated if it would make sense to raise public investment and, if so, under which fiscal rule it is best to do it — whether through tax financing, debt financing, or a reduction of public consumption. We construct and simulate a competitive general equilibrium model, calibrated to Brazilian economy, in which public capital is a component of the production function and public consumption directly affects individuals’ well-being. After assessing the impacts of alternative fiscal rules, the paper concludes that the most desirable financing scheme is the reduction of public consumption, which dominates the others in terms of output and welfare gains. The model replicates the observed growth slowdown of the Brazilian economy when we increase taxes and reduce public capital formation to the levels observed after 1980 and shows that the growth impact of the expansion of tax collection in Brazil was much larger than that of public investment compression.

Decision rules and information provision : monitoring vs manipulation

We analyze the contractual design problem of a principal who delegates decision-making and information provision. The principal faces two tasks: he has to decide the level of discretion to be granted to the decision-maker and to establish who is in charge of supplying the information. We show that these two choices are intrinsically related. When the decision-maker is granted high discretion, information provision is optimally delegated to the parties directly affected by the decision. Conversely, when the decision-maker enjoys little discretion, it is more desirable to rely on a third impartial agent. The paper helps rationalize some organizational arrangements that are commonly observed in the context of judicial and antitrust decision-making.

Robustness and stabilization properties of monetary policy rules in Brazil

Based on three versions of a small macroeconomic model for Brazil, this paper presents empirical evidence on the effects of parameter uncertainty on monetary policy rules and on the robustness of optimal and simple rules over different model specifications. By comparing the optimal policy rule under parameter uncertainty with the rule calculated under purely additive uncertainty, we find that parameter uncertainty should make policymakers react less aggressively to the economy's state variables, as suggested by Brainard's "conservatism principIe", although this effect seems to be relatively small. We then informally investigate each rule's robustness by analyzing the performance of policy rules derived from each model under each one of the alternative models. We find that optimal rules derived from each model perform very poorly under alternative models, whereas a simple Taylor rule is relatively robusto We also fmd that even within a specific model, the Taylor rule may perform better than the optimal rule under particularly unfavorable realizations from the policymaker' s loss distribution function.

Rules of origin: an unfinished negotiation

Many countries are also engaged in trade negotiations on FTAs. RO are a central theme on each of theses fronts. A detailed analysis of the key questions surrounding the harmonization process is compelling, given that RO talks at the WTO will affect the negotiation of FTAs. Many developing countries are waiting the results from WTO to define their own RO. Since the impasse continues, they are creating their own systems and multiplying different ROs to satisfy their needs. This article seeks to provide some clues why it was impossible, till now, to finish this multilateral negotiation. It is organized as follows: i) review of the main issues in the ARO; ii) present the main points of contention in the harmonization work; iii) analyze the implications of a harmonized system of rules of origin to the other major WTO agreements as well as to other national trade policy instruments; and to present some possible scenarios how to conclude the negotiation

Neutralizing the tendency to the overvaluation of the exchange rate or assuming a foreign constraint and asking for foreign savings

The objectives of these notes are two. The first objective is to analyze whether the strategy of growth with absorption of foreign savings leads to a trajectory of the economy that is sustainable in the long run. The second one is to evaluate the possibility of success of a policy of administered devaluation of the exchange rate in Brazil.

Trade rules and exchange rate misalignments : in search for a WTO solution e medidas compensatórias

The debate on the link between trade rules and rules on exchange rates is raising the attention of experts on international trade law and economics. The main purpose of this paper is to analyze the impacts of exchange rate misalignments on tariffs as applied by the WTO – World Trade Organization. It is divided into five sections: the first one explains the methodology used to determine exchange rate misalignments and also presents its results for Brazil, US and China; the second summarizes the methodology applied to calculate the impacts of exchange rate misalignments on the level of tariff protection through an exercise of “misalignment tariffication”; the third examines the effects of exchange rate variations on tariffs and their consequences for the multilateral trading system; the fourth one creates a methodology to estimate exchange rates against a currency of the World and a proposal to deal with persistent and significant misalignments related to trade rules. The conclusions are present in the last section

Graphical constraints: a graphical user interface for constraint problems

A constraint satisfaction problem is a classical artificial intelligence paradigm characterized by a set of variables (each variable with an associated domain of possible values), and a set of constraints that specify relations among subsets of these variables. Solutions are assignments of values to all variables that satisfy all the constraints. Many real world problems may be modelled by means of constraints. The range of problems that can use this representation is very diverse and embraces areas like resource allocation, scheduling, timetabling or vehicle routing. Constraint programming is a form of declarative programming in the sense that instead of specifying a sequence of steps to execute, it relies on properties of the solutions to be found, which are explicitly defined by constraints. The idea of constraint programming is to solve problems by stating constraints which must be satisfied by the solutions. Constraint programming is based on specialized constraint solvers that take advantage of constraints to search for solutions. The success and popularity of complex problem solving tools can be greatly enhanced by the availability of friendly user interfaces. User interfaces cover two fundamental areas: receiving information from the user and communicating it to the system; and getting information from the system and deliver it to the user. Despite its potential impact, adequate user interfaces are uncommon in constraint programming in general. The main goal of this project is to develop a graphical user interface that allows to, intuitively, represent constraint satisfaction problems. The idea is to visually represent the variables of the problem, their domains and the problem constraints and enable the user to interact with an adequate constraint solver to process the constraints and compute the solutions. Moreover, the graphical interface should be capable of configure the solver’s parameters and present solutions in an appealing interactive way. As a proof of concept, the developed application – GraphicalConstraints – focus on continuous constraint programming, which deals with real valued variables and numerical constraints (equations and inequalities). RealPaver, a state-of-the-art solver in continuous domains, was used in the application. The graphical interface supports all stages of constraint processing, from the design of the constraint network to the presentation of the end feasible space solutions as 2D or 3D boxes.

As sanções políticas, mecanismo de intervenção do estado na ordem econômica e tributária

This work pursues to analyze the sanctions of restrictive nature, which are characterized by impeding the business of the contributor in debt. Such sanctions known as political sanctions, are truly understood as an indirect way of tax enforcement, liable to cause problems to the private entity in curtailing, the initiative freedom, opposing the Article 5°, item XIII and Article 170, single paragraph of CF/88. As the State gets the several means to assure the economic order effective performance, it is up to the State to restrain the economic power abuse that objects to the marketing domination, to the ending of competition, and arbitrary increasing of profits (CF Article 173, § 4ª.) Therefore, it depends on the state, besides maintaining the economic order, to ensure a fair distribution of tax burden and act under the command of the Democratic State of Law principles. In order to make the tax collection effective, specific in some cases, the administrative fiscal agent uses coercive, excessive, and institutional, in imposing sanctions which causes constraint, maculating the contributor s essential rights, that matters of the necessity to force the tax credit ending. The principle of the free initiative and free competition, which are intended to be analyzed in this study, comes from a constitutional context and it will be reviewed in its systematic relations and with another rules, in order to evidence, at the end, the occurrence of an intervention towards the economic order when the State makes do of political sanctions as a tool for the tax credit effectiveness, infringing the Tax and Constitutional principles

A method for plotting the complementary root locus using the root-locus (positive gain) rules

The root-locus method is a well-known and commonly used tool in control system analysis and design. It is an important topic in introductory undergraduate engineering control disciplines. Although complementary root locus (plant with negative gain) is not as common as root locus (plant with positive gain) and in many introductory textbooks for control systems is not presented, it has been shown a valuable tool in control system design. This paper shows that complementary root locus can be plotted using only the well-known construction rules to plot root locus. It can offer for the students a better comprehension on this subject. These results present a procedure to avoid problems that appear in root-locus plots for plants with the same number of poles and zeros.

Rhamnolipid emulsifying activity and emulsion stability: pH rules

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)