Asset Price Dynamics in a Chartist-Fundamentalist Model with Time Delays: A Bifurcation Analysis

This paper studies the dynamic behavior of asset prices using a chartist-fundamentalist model with two speculative markets. To this effect, we employ a differential system with delays à la Dibeh (2007) to describe the price dynamics and we assume that the two markets are coupled via diffusive coupling terms. We study two different time delay cases, namely, when both markets experience the same time delay and when the time delay is different across markets. First, we theoretically determine that the equilibrium exists and investigate its stability. Second, we establish the general conditions for the existence of local Hopf bifurcations and analyze their direction and stability. The common conclusion from both the delay scenarios we consider is that coupled speculative markets with heterogeneous agents in each, but with different price dynamics, can be synchronized through diffusive coupling. Finally, we provide some numerical illustrations to confirm our theoretical findings

RESEARCH ON THE POROSITY OF THE MESO-METAMORPHIC CRYSTALLINE SCHIST IN SOME SCREE IN LEAOTA MOUNTAINS

Scree, as the main result of the gelivation (gelifraction) processes, represents a very interesting habitat type through the ecologic particularities it has. The formation and the spreading of scree is strongly related to the type of rock that generated it. Different types of rock lead to a different behavior against gelifraction and also against meteorization and bio-meteorization (chemical and biochemical alteration). Some of the mechanical features of rocks are defining regarding the higher or lower susceptibility of generating scree. The present paper is the result of the research on the porosity of meso-metamorphical crystalline schist extracted from different types of scree located on the north-western side of Leaota Mountains. It represents the continuation of some research of similar researches on limestone scree in the previously mentioned geographical area, leading to the conclusion that one can make a comparison between the two categories of rocks (limestone and schist) regarding their porosity and the way through which this geo-mechanical feature makes its mark on their behavior against the action of external features. The present paper is part of a complex assembly of researches on the way through which the geological component of the mesovoid shallow substratum (MSS) (in our case, the scree) leads, in a direct or indirect manner, to defining ecologic particularities of this habitat type and thus it influences the distribution of some zoocoenosis components

Fiscal Policy During Absorption Cycles

Domestic absorption cycles are relevant in assessment and design of fiscal policies. Our cross-country analysis covers 59 advanced and emerging countries for the 1990-2009 period. We show that ignoring domestic absorption cycles leads to biased fiscal stance indicators, for both advanced and emerging economies, by up to 1.5 percent of GDP. The estimates of fiscal policy reaction functions indicate that absorption booms are associated with pro-cyclical fiscal policy. We tackle the endogeneity problem in reactions functions through stripping the cyclical component of the fiscal aggregates. We also find that simple filtering methods in the computation of absorption gaps perform as better as indirect methods of estimating trade balance gaps and stripping of output gaps.Developed countries;Economic growth;Economic models;Emerging markets;Indirect taxation;Revenue sources;Revenues;fiscal policy, fiscal stance, fiscal aggregates, structural fiscal, fiscal stances, fiscal reaction, fiscal balance, fiscal balances, tax base, fiscal reaction functions, data availability, cyclical fiscal policy, fiscal policies, fiscal reaction function, government spending, fiscal affairs, fiscal affairs department, fiscal behavior, fiscal space, public debt, tax revenues, budget balance, public finances, fiscal impulse, fiscal indicators, data sources, fiscal revenues, budget balances, fiscal sustainability, fiscal cost, tax collections, tax bases, changes in output, discretionary fiscal policy, tax system, long-run fiscal stance, fiscal expansion, country evidence, fiscal authorities, fiscal position, expenditure ratio, fiscal situation, tax revenue, tax structure, fiscal policy decisions, fiscal deficits, taxation, data requirements, fiscal consolidation

THE STUDY OF THE POROSITY OF THE LIMESTONES IN SOME OF THE SCREE IN LEAOTA MASSIF

The screes are the result of interaction between pre-existing rocks and exogenous agents, forming by mechanical disintegration processes, mainly due to cryoclastic (gelivation) processes. Cryoclastic processes are generated by the pressure exerted by water from pores or cracks and microcracks of the rocks. The result of these processes is known in the literature as cryo-nival relief. The main representatives of the cryo-nival relief are the screes; these are detritus mobile rocks, with angular ranges of various sizes (unsorted). This scree, in most cases, are areas that are unaffected or less anthropically affected; they represent habitats with certain microclimatic peculiarities, named mesovoid shallow substrate (MSS) or shallow subterranean habitats (SSHs) by the specialists. These terms being outlined and being used more and more frequently since the 1980s. One of the most important peculiarities of the MSS is represented by the high relative humidity values, a main ecological factor that depends on the interclastic porosity but also on the microporosity of the clasts that are part of the scree. Moreover, the processes of chemical and biochemical alteration are dependent on the presence of water in the rocks and therefore, indirectly, on porosity. For this reason, we examined the porosity of limestone clasts belonging to the scree. The generation of the scree itself, disgregation process on the masses, depends on the geomechanical characteristics of the rocks from which the nude slopes are made, how rock behaves in the cryoclasting processes, which is fundamentally influenced by porosity

The determinants of performance in building infrastructure in transition economies

We investigate how contract specificities affect the performance of municipal infrastructure projects in transportation, district heating, water, waste water and solid waste. Using data from projects financed by the European Bank for Reconstruction and Development (EBRD), we look at the effect of involving private parties with different degrees of risk, and involving public parties other than the respective municipality. In particular, central authorities may provide a sovereign guarantee for the funds lent by the Bank. We construct two types of performance measures. First, timeliness of the projects is measured by (i) the total length of delays, (ii) the delays between signing and disbursement of funds and (iii) the occurrence of political disruptions of the projects. Secondly, to measure financial and commercial performance we look at whether (iv) financial covenants and (v) covenants about tariffs for infrastructure use were reached. We find that private participation without commercial risk (for instance, works or turnkey projects) tends to increase project performance. Private participation with commercial risk has no significant effect on project performance. Sovereign guarantees reduce delays but also decrease financial discipline. These effects are robust against potential selection effects, which we control for through instrumental variable regressions.public private, contracts, sovereign guarantee, risk sharing

Assessing Fiscal Stress

This paper develops a new index which provides early warning signals of fiscal sustainability problems for advanced and emerging economies. Unlike previous studies, the index assesses the determinants of fiscal stress periods, covering public debt default as well as near-default events. The fiscal stress index depends on a parsimonious set of fiscal indicators, aggregated using the approach proposed by Kaminsky, Lizondo and Reinhart (1998). The index is used to assess the build up of fiscal stress over time since the mid-1990s in advanced and emering economies. Fiscal stress has increased recently to record-high levels in advanced countries, reflecting raising solvency risks and financing needs. In emerging economies, risks are lower than in mature economies owing to sounder fiscal fundamentals, but fiscal stress remains higher than before the crisis.Developed countries;Developing countries;Economic models;Fiscal sustainability;Sovereign debt;fiscal stress, public debt, fiscal indicators, fiscal crisis, fiscal variables, debt default, government debt, fiscal distress, fiscal crises, debt crises, short-term debt, fiscal vulnerability, external debt, sovereign bond, sovereign default, public debt crises, currency crises, debt defaults, fiscal solvency, fiscal adjustment, current account, fiscal policy, currency debt, sovereign debt crises, fiscal affairs, debt obligations, external borrowing, debt restructuring, fiscal affairs department, fiscal risks, short term debt, foreign currency debt, repayment capacity, fiscal outlook, official creditors, domestic currency, fiscal policies, reserve bank, debt exchanges, debt maturity, fiscal difficulties, fiscal data, debt management, domestic public debt, national debt, domestic investor, net debt, currency crisis, debt structure, currency risk, fiscal pressure, deficit financing, fiscal component, fiscal factors, fiscal risk, debt default episodes, currency composition