The generalized bin packing problem

In the Generalized Bin Packing Problem (GBPP), given two sets of compulsory and non-compulsory items characterized by volume and profit and a set of bins with given volume and cost, we want to select the subset of profitable non-compulsory items to be loaded together with the compulsory ones into the appropriate bins in order to minimize the total net cost. Lower and upper bounds to the GBPP are given. The results of extensive computational experiments show that the proposed procedures are efficient and the bounds are tight.     

COMMODITY CONTENT IN A GENERAL INPUT–OUTPUT MODEL: A COMMENT

This paper critically analyses the approach to the determination of values, or commodity contents, developed by Fujimoto and Opocher in 2009. Even setting aside various problematic definitional issues, the broader implications of the approach for classical theory are unclear. First, the value‐theoretic definitions of skill differentials and bads capture at best necessary conditions and it is unlikely that such definitions can be provided by focusing only on the technological data of the economy. Second, the approach has various interesting implications concerning the relation between productiveness and exploitation that directly contradict some of the authors' claims.     

Threshold bipower variation and the impact of jumps on volatility forecasting

This study reconsiders the role of jumps for volatility forecasting by showing that jumps have a positive and mostly significant impact on future volatility. This result becomes apparent once volatility is separated into its continuous and discontinuous components using estimators which are not only consistent, but also scarcely plagued by small sample bias. With the aim of achieving this, we introduce the concept of threshold bipower variation, which is based on the joint use of bipower variation and threshold estimation. We show that its generalization (threshold multipower variation) admits a feasible central limit theorem in the presence of jumps and provides less biased estimates, with respect to the standard multipower variation, of the continuous quadratic variation in finite samples. We further provide a new test for jump detection which has substantially more power than tests based on multipower variation. Empirical analysis (on the S&P500 index, individual stocks and US bond yields) shows that the proposed techniques improve significantly the accuracy of volatility forecasts especially in periods following the occurrence of a jump.     

How Effective are WTO Disciplines on Domestic Support and Market Access for Agriculture?

A new round of trade negotiations through the World Trade Organization (WTO) was launched in 2001. One of the major aims of the Doha Development Round is to reduce agricultural protection and impose greater discipline on domestic agricultural subsidies, particularly those that are the most trade distorting. In this article, we examine whether the proposed WTO modalities for agriculture will actually achieve this aim in Norway, which ranks among the top providers of government assistance for agriculture. Norway has a complex system of farm subsidies buttressed by substantial import protection. The extent to which its agricultural support policies will have to change in response to new WTO disciplines provides an important indication of how successful these are likely to be. We find that Norway will probably be able to sustain its current agricultural activity and production levels while staying within the new WTO rules. Following recent practice in some other WTO members, Norway will be able to reduce its notified support without making real changes in some of its programmes. However, there will have to be a shift from market price support, which is paid for by consumers through higher food prices, to budgetary support paid by taxpayers. This could generate increased domestic pressure for policy reform.     

MULTIDIMENSIONAL DISTANCE‐TO‐COLLAPSE POINT AND SOVEREIGN DEFAULT PREDICTION

By focusing on sovereign defaults, this paper introduces a multidimensional distance‐to‐collapse point based on a two‐step procedure. The first step is nonparametric and provides an early warning system that signals a potential crisis whenever preselected leading indicators exceed specific thresholds. The second is parametric and incorporates the first‐step country default predictors within a probit specification. Such a two‐step procedure generalizes the distance‐to‐default à la Merton within a multidimensional setting, wherein we care about the distance of each indicator from its threshold. Empirical evidence about debt crises of emerging markets over the period 1975–2002 proves that our methodology predicts 80% of the total defaults and non‐defaults in and out of sample. Copyright © 2012 John Wiley & Sons, Ltd.     

Dynamics of intraday serial correlation in the Italian futures market

The serial correlation of high‐frequency intraday returns on the Italian stock index futures (FIB30) in the period 2000–2002 is studied. It is found that intraday autocorrelation is mostly negative for time scales lower than 20 minutes, mainly due to the bid–ask bounce effect. Although this supports the efficiency of the Italian futures market, evidence that intraday serial correlation becomes positive in high‐volatility regimes is also provided. Moreover, it is found that it is mainly unexpected volatility that makes serial correlation rise, and not its predictable part. The results are supportive of the K. Chan (1993) model. © 2006 Wiley Periodicals, Inc. Jrl Fut Mark 26:61–84, 2006     

Applications of parameters of shape to statistical distributions

Several new parameters characterizing the shape of statistical distributions are discussed. These parameters have earlier been considered for characterization of the shape of territories. By means of these parameters we describe general spread and spread along the axes, as well as asymmetry, of univariate theoretical and empirical distributions. General formulas for the parameters are given, and the particular formulas for the most of the common theoretical distributions are also listed. Some numerical values are tabulated, to illustrate their usefulness. Affine transformations are considered, and many applications and extensions are hinted upon.     

“Set a Sufficiently Ambitious Budget Target and Let the Automatic Stabilizers Work”. Will it Really Work in the European Monetary Union?

We examine the popular recipe in the title by means of an AD-LM-AS two-country model of the EMU, controlling for asymmetry in demand and supply shocks and in the monetary-policy transmission mechanism. Unless structural symmetry holds and symmetric shock occurs, national automatic stabilizers, even though supplemented with the common monetary policy, cannot deliver optimal stabilization in each economy. Inflation and output gaps are not closed and may be divergent in sign. Considering that a federal system of inter-regional insurance is lacking, the recipe under examination is too optimistic, while serious threat to EMU cohesion may arise. The econometric estimates we present show that existing national fiscal systems work very poorly as for the minimization, after shocks, of the dispersion of national incomes around the EMU average.     

On the performance of the Chow-Lin procedure for quarterly interpolation of annual data: Some Monte-Carlo analysis

Most of the countries of the OECD offer quarterly estimates of their national growth or of their Gross National Product. Official Statistical Agencies in western countries have to deal with the problem of estimating Quarterly National Accounts series congruently with Annual National Accounts. In Spain, the Instituto Nacional de Estadística uses the Chow-Lin disaggregation method, which is based on information provided by a group of high-frequency related variables, to estimate the quarterly components of National Accounts from annual components. In this paper, we analyse the relative quality of the estimates obtained through the Chow-Lin procedure, under different sets of hypotheses.JEL Classification: C15, C43, M40We are grateful to Maria Amparo Ripoll for her assistance. The authors also wish to thank three anonymous referees and an editor for their constructive suggestions and comments. This research was partially made during the stay of the first author at the Universidad Carlos III de Madrid. It has been partially supported by the research project DGCYT PB98-1460.     

Discretionary monetary policy and the zero lower bound on nominal interest rates

Ignoring the existence of the zero lower bound on nominal interest rates one considerably understates the value of monetary commitment in New Keynesian models. A stochastic forward-looking model with an occasionally binding lower bound, calibrated to the U.S. economy, suggests that low values for the natural rate of interest lead to sizeable output losses and deflation under discretionary monetary policy. The fall in output and deflation are much larger than in the case with policy commitment and do not show up at all if the model abstracts from the existence of the lower bound. The welfare losses of discretionary policy increase even further when inflation is partly determined by lagged inflation in the Phillips curve. These results emerge because private sector expectations and the discretionary policy response to these expectations reinforce each other and cause the lower bound to be reached much earlier than under commitment.