Underground economy and aggregate fluctuations

This paper explores the role of underground economic activities as an explanation of differences in registered aggregate fluctuations. In order to do so, we introduce an underground economy sector in an otherwise standard Real Business Cycle model and calibrate it to the USA economy. We find that, at low frequencies, Europe fluctuates more than the USA, while its participation rate is smaller. The existence of underground activities rationalizes the negative relationship between participation rates and fluctuations of registered output. Our model accounts for 44.3% of the differences in aggregate fluctuations between the USA and European economies. Finally, the model generates implied sizes of the underground economy of 3.2% and 7% of the American and European output, respectively, which are in the range of those found in the empirical literature.     

An autonomous multi-agent approach to supply chain event management

Organizations have made a significant effort to implement software for planning and scheduling, but disruptive event management is still a problem to be solved. Since a disruptive event can affect the overall performance of the supply chain, SCEM (Supply Chain Event Management) systems presenting different automation levels such as monitoring, alarm and decision support have been proposed. However, the management of disruptive events, taking into account the distributed nature of the supply chain, the members' autonomy and the ability to exert corrective control actions, has been identified as a problem that requires further research. This work presents an agent-based approach for the SCEM problem, which can perform autonomous corrective control actions to minimize the effect of deviations in the plan that is currently being executed. These control actions consist of a distribution of the variation between supply chain members, using the plan's slack in a collaborative way. An innovative feature of this approach is its focus on resources, which are affected by disruptive events in a direct way. Based on this approach, a SCEM system is designed as a net of control points defined on resources connected through supply process orders. Two novel aspects are the distributed collaborative inter-organizational architecture of the SCEM system and a Double Contract Net Protocol. This protocol allows a set of resource:representing agents to interact through an agent, representing a supply process order as a mediator. An application to a case study of the Multi-Agent SCEM system implemented with JADE is provided.     

GROWING LIKE SPAIN: 1995–2007

Measured total factor productivity (TFP) fell in Spain during the boom years of 1995–2007. Using administrative data from the quasi-universe of firms, we show that there was an increase in misallocation, which was more severe in sectors where connections with public officials are more important for business success. We write and estimate a simple model of cronyism in which heterogeneous firms invest in political connections. Our quantitative exercise concludes that the institutional decline over this period costed 1.9% growth in TFP per year and a 0.8% annual increase in the resources spent by firms in establishing political connections.     

Run length analysis of Shewhart charts applied to drifting processes under an integrative SPC/EPC model

Engineering Process Controllers (EPC) are frequently based on parametrized models. If process conditions change, the parameter estimates used by the controllers may become biased, and the quality characteristics will be affected. To detect such changes it is adequate to use Statistical Process Control (SPC) methods. The run length statistic is commonly used to describe the performance of an SPC chart. This paper develops approximations for the first two moments of the run length distribution of a one-sided Shewhart chart used to detect two types of process changes in a system that is regulated by a given EPC scheme: i) changes in the level parameter; ii) changes in the drift parameter. If the drift parameter shifts, it is further assumed that the form of the drift process changes from a linear trend under white noise (the in-control drift model) into a random walk with drift model. Two different approximations for the run length moments are presented and their accuracy is numerically analyzed. Received: August 1998     

Polychoric versus Pearson correlations in exploratory and confirmatory factor analysis of ordinal variables

Given that the use of Likert scales is increasingly common in the field of social research it is necessary to determine which methodology is the most suitable for analysing the data obtained; although, given the categorization of these scales, the results should be treated as ordinal data it is often the case that they are analysed using techniques designed for cardinal measures. One of the most widely used techniques for studying the construct validity of data is factor analysis, whether exploratory or confirmatory, and this method uses correlation matrices (generally Pearson) to obtain factor solutions. In this context, and by means of simulation studies, we aim to illustrate the advantages of using polychoric rather than Pearson correlations, taking into account that the latter require quantitative variables measured in intervals, and that the relationship between these variables has to be monotonic. The results show that the solutions obtained using polychoric correlations provide a more accurate reproduction of the measurement model used to generate the data.     

Indirect estimation of large conditionally heteroskedastic factor models,with an application to the Dow 30 stocks

We derive indirect estimators of conditionally heteroskedastic factor models in which the volatilities of common and idiosyncratic factors depend on their past unobserved values by calibrating the score of a Kalman-filter approximation with inequality constraints on the auxiliary model parameters. We also propose alternative indirect estimators for large-scale models, and explain how to apply our procedures to many other dynamic latent variable models. We analyse the small sample behaviour of our indirect estimators and several likelihood-based procedures through an extensive Monte Carlo experiment with empirically realistic designs. Finally, we apply our procedures to weekly returns on the Dow 30 stocks.     

A Reconsideration of Tax Shield Valuation

A quarter‐century ago, Miles and Ezzell (1980) solved the valuation problem of a firm that follows a constant leverage ratio L = D/S. However, to this day, the proper discounting of free cash flows and the computation of WACC are often misunderstood by scholars and practitioners alike. For example, it is common for textbooks and fairness opinions to discount free cash flows at WACC with beta input β _S = [1 + (1 ? τ)L]β_u, although the latter is not consistent with the assumption of constant leverage. This confusion extends to the valuation of tax shields and the proper implementation of adjusted present value procedures. In this paper, we derive a general result on the value of tax shields, obtain the correct value of tax shields for perpetuities, and state the correct valuation formulas for arbitrary cash flows under a constant leverage financial policy.     

Reserves,Sovereign Wealth Funds and the Resilience of Global Imbalances

Reserves and sovereign wealth funds (SWFs) assets should be jointly considered for the assessment of global imbalances, hence their denomination as sovereign external assets (SEAs): both are public capital outflows from developing to developed countries, both hinder adjustment in current account surplus and deficit countries and, therefore, both contribute to sustain global imbalances. They represented 135 per cent and 50 per cent of net and gross US financing needs, respectively, in 2007. Reserves contribute 80 per cent and SWFs 20 per cent. They will go on providing resilience to the global imbalances, and the relative importance of SWFs is set to increase if commodity prices stay high.     

Internal and external exchange rate equilibrium in a cointegration framework. An application to the Spanish peseta

A simple cointegration methodology is used to compute the equilibrium real exchange rate for the peseta. The stock of foreign assets and the evolution of sectoral prices are considered to be the fundamentals for the real exchange rate. After testing for cointegration, we proceed to decompose the series into a permanent and a transitory component, following the method devised by Gonzalo and Granger. The permanent component of the real exchange rate corresponds to its (time-varying) equilibrium value, and the deviation of the actual real exchange rate from this equilibrium value gives an estimation of the degree of misalignment of the real exchange rate. By the end of the sample (1998:1), the peseta is estimated to be undervalued around 6%.     

Market Orientation and Internationalization in Small and Medium‐Sized Enterprises

This article builds on studies from the literature on market orientation (MO) and internationalization to develop a model and a set of hypotheses regarding the relationships among MO, knowledge acquisition (KA), and market commitment (MC), and the direct and indirect effects of these variables on the performance of small and medium‐sized enterprises (SMEs) in foreign markets. The model and its hypotheses are tested by means of an empirical study of a multi‐industry sample of Spanish SMEs operating in foreign markets. The results, obtained by structural equation modeling, indicate that a direct positive relationship exists between MO and a strategy of internationalization, and that the effect of MO on performance in foreign markets is moderated by KA and MC.