Testing SDRT's Right Frontier

The Right Frontier Constraint (RFC), as a constraint on the attachment of new constituents to an existing discourse structure, has important implications for the interpretation of anaphoric elements in discourse and for Machine Learning (ML) approaches to learning discourse structures. In this paper we provide strong empirical support for SDRT's version of RFC. The analysis of about 100 doubly annotated documents by five different naive annotators shows that SDRT's RFC is respected about 95% of the time. The qualitative analysis of presumed violations that we have performed shows that they are either click-errors or structural misconceptions

How a regulatory capital requirement affects banks' productivity: an application to emerging economies

© 2015, Springer Science+Business Media New York. This paper presents a novel approach to measure efficiency and productivity decomposition in the banking systems of emerging economies with a special focus on the role of equity capital. We model the requirement to hold levels of a fixed input, i.e. equity, above the long run equilibrium level or, alternatively, to achieve a target equity-asset ratio. To capture the effect of this under-leveraging, we allow the banking system to operate in an uneconomic region of the technology. Productivity decomposition is developed to include exogenous factors such as policy constraints. We use a panel data set of banks in emerging economies during the financial upheaval period of 2005–2008 to analyse these ideas. Results indicate the importance of the capital constraint in the decomposition of productivity

Wealth Effects and Public Debt in an Endogenous Growth Model. Banca d'Italia Public Finance Workshop "Fiscal Sustainability : Analytical Developments and Emerging Policy Issues", Perugia, 3-5 April 2008.

The debate on public finances’ sustainability has long focused on the conditions for the accumulation of debt. This implied that, empirically, the analyses revolved around estimations of dynamic versions of the debt accumulation equation, through unit root tests and cointegration tests between e.g. revenues and primary expenditures, or debt and deficit. Bohn (2007, Journal of Monetary Economics), has forcefully argued in favour of a stronger focus on theory. The model of this paper shows to which extent and under which conditions earlier results considering fiscal policy in an endogenous growth setting are modified if government spending is not entirely tax-financed. Therefore the model uses Barro’s (1990, Journal of Political Economy) production function and Blanchard (1985, Journal of Political Economy)-type consumers to assess fiscal sustainability and the determinants of long-run (or potential) growth, in presence of productive capital services. The main conclusion is that, provided public spending is not too high, it will be growth-enhancing. This feature does not hurt fiscal sustainability if taxes are adjusted appropriately. We also calibrate the model to show that the current level of public capital is low in France, the UK and the USA.

THE MARGINAL COST OF AGRI-ENVIRONMENTAL SERVICES

agri-environmental services, bio-economic modelling, economies of scale and scope, Environmental Economics and Policy, Land Economics/Use, Research Methods/ Statistical Methods, Q18, Q57, Q58,

An Approach to Ecosystem-Based Fishery Management

Marine scientists and policymakers are encouraging ecosystem-based fishery management (EBFM), but there is limited guidance on how to operationalize the concept. We adapt financial portfolio theory as a method for EBFM that accounts for species interdependencies, uncertainty, and sustainability constraints. Illustrating our method with routinely collected data available from the Chesapeake Bay, we demonstrate the gains from taking into account species variances and covariances in setting species total allowable catches. We find over the period from 1962–2003 that managers could have increased the revenues from fishing and reduced the variance by employing ecosystem frontiers in setting catch levels.ecosystem-based fishery management, portfolio, trophic modeling, precaution

Evaluating Agri-Environmental Schemes – The Marginal Costs of Ecosystem Services

We provide a new approach for assessing the cost of marginal ecosystem changes and the effectiveness of agri-environmental schemes. The approach is based on a theoretical and empirical analysis of the bio-economic production interactions between marketed outputs and non-marketed ecosystem services at the micro level. To frame the economic nature of the problem, we employ a generalized joint production model in combination with cost minimization. The generalized joint production framework allows for the consideration of complementary, substitutive and competitive relationships between agricultural production and non-marketed ecosystem services generation and avoids double counting. From this theoretical model we distinguish three theoretical cases depending on the imposed minimum acceptable level of the non-marketed ecosystem services. We employ farm level panel data for the UK to empirically investigate these cases. More specifically, to represent and evaluate the production structure, we estimate first- and second-order elasticities derived from a flexible transformation function. Results show that the majority of farms produce agricultural output and ecosystem services in a complementary relationship. Generation of multiple ecosystem services on the same farm showed either a substitutive or competitive relationship. A change in the composition of the ecosystem services output would have very different implications for individual farms.agri-environmental services, bio-economic modelling, economies of scale and scope, Agricultural and Food Policy, Environmental Economics and Policy, Q18, Q57, Q58.,

Marketed Outputs and Non-Marketed Outputs: The Marginal Costs of Producing Ecosystem Services

We provide a new approach for assessing the cost of marginal ecosystem changes and the effectiveness of green payment schemes. The approach is based on a theoretical and empirical analysis of the bio-economic production interactions between marketed outputs and non-marketed ecosystem services at the micro level. To frame the economic nature of the problem, we employ a generalized joint production model in combination with cost minimization. The generalized joint production framework allows for the consideration of complementary, supplementary and competitive relationships between agricultural production and non-marketed ecosystem services generation and avoids double counting. From this theoretical model we distinguish three theoretical cases depending on the imposed minimum acceptable level of the non-marketed ecosystem services. We employ farm level panel data for the UK to empirically investigate these cases. More specifically, to represent and evaluate the production structure, we estimate first- and second-order elasticities derived from a flexible transformation function. Results show that the majority of farms produce agricultural output and ecosystem services in a complementary relationship. Generation of multiple ecosystem services on the same farm showed either a supplementary or competitive relationship. Changing the composition of the ecosystem services output would have very different implications for individual farms.ecosystem services, green payments, bio-economic modelling, economies of scale and scope, program evaluation., Environmental Economics and Policy, Land Economics/Use, Q18, Q57, Q58.,

The Stochastic Discount Factor: Extending the Volatility Bound and a New Approach to Portfolio Selection with Higher-Order Moments

The authors extend the well-known Hansen and Jagannathan (HJ) volatility bound. HJ characterize the lower bound on the volatility of any admissible stochastic discount factor (SDF) that prices correctly a set of primitive asset returns. The authors characterize this lower bound for any admissible SDF that prices correctly both primitive asset returns and quadratic payoffs of the same primitive assets. In particular, they aim at pricing derivatives whose payoffs are defined as non-linear functions of the underlying asset payoffs. The authors construct a new volatility surface frontier in a three-dimensional space by considering not only the expected asset payoffs and variances, but also asset skewness. The intuition behind the authors' portfolio selection is motivated by the duality between the HJ mean-variance frontier and the Markowitz mean-variance portfolio frontier. The authors' approach consists of minimizing the portfolio risk subject not only to portfolio cost and expected return, as usual, but also subject to an additional constraint that depends on the portfolio skewness. In this sense, the authors shed light on portfolio selection when asset returns exhibit skewness.Financial markets; Market structure and pricing