Structural breaks and financial risk management

There is ample empirical evidence on the presence of structural changes in financial time series. Structural breaks are also shown to contribute to the leptokurtosis of financial returns and explain at least partly the observed persistence of volatility processes. This paper explores whether detecting and taking into account structural breaks in the volatility model can improve upon our Value at Risk forecast. VAR is used by banks as a standard risk measure and is accepted by regulation in setting capital, which makes it an issue for the central bank guarding against systemic risk. This paper investigates daily BUX returns over the period 1995-2002. The Bai-Perron algorithm found several breaks in the mean and volatility of BUX return. The shift in the level of unconditional mean return around 1997-1998 is likely to be explained by the evolving efficiency of the market, but most of all by the halt of a strong upward trend in the preceding period. Volatility jumped to very high levels due to the Asian and Russian crisis. There were longer lasting shift too, most likely due to increasing trading volume. When in-sample forecasts are evaluated, models with SB dummies outperform the alternative methods. According to the rolling-window estimation and out-of-sample forecast the SB models seem to perform slightly better. However the results are sensitive to the evaluation criteria used, and the choice on the probability level.Structural Break tests, volatility forecasting, Value-at-Risk, backtest.

Which sectors make the poor countries so unproductive?

Standard growth accounting exercises find large cross-country differences in aggregate TFP. Here we ask whether specific sectors are driving these differences, and, if this is the case, which these problem sectors are. We argue that to answer these questions we need to consider four sectors. In contrast, the literature typically considers only two sectors. Our four sectors produce services (nontradable consumption), consumption goods (tradable consumption), construction (nontradable investment), and machinery and equipment (tradable investment). Interacting the data from the 1996 benchmark study of the Penn World Tables with economic theory, we find that the TFP differences across countries are much larger in the two tradable sectors than in the two nontradable sectors. This is consistent with the Balassa--Samuelson hypothesis. We also find that within the tradable sectors the TFP differences are much larger in machinery and equipment than in consumption goods. We illustrate the usefulness of our findings by accounting for the conflicting results of the existing two--sector analyses and by developing criteria for a successful theory of aggregate TFP

Measuring Factor Income Shares at the Sectoral Level

Many applications in economics use multi-sector versions of the growth model. In this paper, we measure the income shares of capital and labor at the sectoral level for the U.S. economy. We also decompose the capital shares into the income shares of land, structures, and equipment. We find that the capital shares differ across sectors. For example, the capital share of agriculture is more than two times that of construction and more than 50% larger than that of the aggregate economy. Moreover, agriculture has by far the largest land share, which mostly explains why it has the largest capital share. Our numbers can directly be used to calibrate standard multi-sector models. Alternatively, if one wants to abstract from differences in sector capital shares, our numbers can be used to establish that this is not crucial for the results.input-output tables; industry-by-commodity total requirement matrix; sector factor shares

Independence and heterogeneity in games of incomplete information

This paper provides a sufficient condition for existence and uniqueness of equilibrium, which is in monotone pure strategies, in games of incomplete information. First, we show that if each player’s incremental ex post payoff is uniformly increasing in its own action and type, and its type is sufficiently uninformative of the types of its opponents (independence), then its expected payoff satisfies a strict single crossing property in its own action and type, for any strategy profile played by its opponents. This ensures that a player’s best response to any strategy profile is a monotone pure strategy. Secondly, we show that if, in addition, there is sufficient heterogeneity of the conditional density of types, then the best response correspondence is a contraction mapping. This ensures equilibrium existence and uniqueness. In contrast to existing results, our uniqueness result does not rely on strategic complementarities; this allows for a wider range of applications. <br><br> Keywords; incomplete information, heterogeneity, existence, unique pure strategy equilibrium <br><br> JEL classification: C72; D82

Macro stress testing with sector specific bankruptcy models

This paper employs the methodology of Wilson (1997) on Hungarian data to conduct a macro stress test in relation to banks' corporate loan portfolio. First, sector specific models of bankruptcy are estimated, where the bankruptcy frequency is linked to the general health of the economy. Data on bankruptcy filings in Hungary between 1995 and 2005 are used. Then, after identifying relevant shocks, the estimated models are employed in Monte Carlo simulation to conduct a stress test on the Hungarian banking sector. Various loss measures are defined to quantify the impact of shocks and evaluate the resilience of the Hungarian banking sector. The sensitivity of the stress test results to the endogeneity of LGD and the prevailing macro environment are also examined

Occupational Choice, Financial Market Imperfections and Development

We develop a simple model of occupational choice under financial market im- perfections, in the presence of technological convexities. The aim is to analyze the quantitative effect of these imperfections on the level of income. We find that although their effect is relatively large, financial market imperfections alone are not able to explain the observed cross country difference in income. However, when interacted with the issue of mobility, those imperfections become much more relevant, to the point of pushing the economy into a development trap.

Subsidies, Soft Budget Constraints and Financial Market Imperfections

In this paper we analyze the interaction between subsidies, soft budget con- straints and financial market imperfections in a simple model of occupational choice. The basic message is that the eect of soft budget constraints has to be analyzed jointly with other possible distortions that are affecting the economy. In particu- lar in environments where there are severe forms of financial market imperfections, subsidies and soft budget constraints can ease those imperfections and reduce credit rationing problems. The "positive" effect of soft budget constraints depends also upon the degree of institutional failure of the economy.

The existence and uniqueness of monotone pure strategy equilibrium in Bayesian games

This paper provides a sufficient condition for existence and uniqueness of equilibrium, which is in monotone pure strategies, in games of incomplete information. First, we show that if each player’s incremental ex post payoff is uniformly increasing in its own action and type, and its type is sufficiently uninformative of the types of its opponents (independence), then its expected payoff satisfies a strict single crossing property in its own action and type, for any strategy profile played by its opponents. This ensures that a player’s best response to any strategy profile is a monotone pure strategy. Secondly, we show that if, in addition, there is sufficient heterogeneity of the conditional density of types, then the best response correspondence is a contraction mapping. This ensures equilibrium existence and uniqueness. In contrast to existing results, our uniqueness result does not rely on strategic complementarities; this allows for a wider range of applications. Keywords; incomplete information, heterogeneity, existence, unique pure strategy equilibrium

Determinacy with Capital Adjustment - Costs and Sector-Specific Externalities

This paper explores the stability properties of the steady state in the standard two-sector real business cycle model with a sector-specific externality in the capital-producing sector. When the steady state is stable then equilibrium is indeterminate and stable sunspots are possible. We find that capital adjustment costs of any size preclude stable sunspots for every empirically plausible specification of the model parameters. More specifically, we show that when capital adjustment costs of any size are considered, a necessary condition for the existence of stable sunspots is an upward- sloping labor demand curve in the capital-producing sector, which in turn requires an implausibly strong externality. This result contrasts sharply with the standard result that when we abstract from capital adjustment costs, stable sunspots occur in the two-sector model for a wide range of plausible parameter values.capital adjustment costs, determinacy, indeterminacy, sector-specific externality, sunspots

Neoclassical Growth Model with Externalities

This paper explores the local stability properties of the steady state in the twosector neoclassical growth model with sector–specific externalities. We show analytically that capital adjustment costs of any size preclude local indeterminacy nearby the steady state for every empirically plausible specification of the model parameters. More specifically, we show that when capital adjustment costs of any size are considered, a necessary condition for local indeterminacy is an upward-sloping labor demand curve in the capital-producing sector, which in turn requires an implausibly strong externality. We show numerically that capital adjustment costs of plausible size imply determinacy nearby the steady state for empirically plausible specifications of the other model parameters. These findings contrast sharply with the previous finding that local indeterminacy occurs in the two-sector model for a wide range of plausible parameter values when capital adjustment costs are abstracted from.capital adjustment costs; determinacy; externality; local indeterminacy; stability.