Gastric liposarcoma: CT appearance

Two cases of liposarcoma of the stomach are described. At computed tomography (CT) the neoplasms showed features of an aggressive malignant tumor, with no fatty values within. We discuss the differential diagnosis of such lesions and conclude that, although rare, liposarcoma should be considered as a possible diagnosis when a large exophytic gastric mass is detected at CT.     

Technical efficiency,specialization and ownership form: evidences from a pooling of Italian hospitals

We evaluate how the productive structure and level of specialization of a hospital affect technical efficiency by analyzing a six-year panel database (2000/2005) drawn from hospital discharge records and Ministry of Health data. We adopt a distance function approach, while measuring the technical efficiency level with stochastic frontier techniques. After controlling for environmental variables and hospital case-mix, inefficiency is negatively associated with specialization and positively associated with capitalization. Capitalization is typical of private structures which, on average, use resources less efficiently with respect to public and not-for-profit hospitals. Finally, by looking at scale elasticities, we find some evidence of unexploited economies of scale, leaving room for centralization.     

Services trade and credit frictions: Evidence with matched bank–firm data

The effects of credit supply shocks on the exports of services are not clear a priori. On the one hand, services need lower initial investment in physical capital than manufacturing. On the other hand, competitiveness for exporting services requires investments in intangible capital and in product customisation that may be subject to credit frictions. Using Italian matched bank–firm data and focusing on the sovereign debt crisis, we find an elasticity of services exports to credit supply, between 0.3 and 0.4. The effects of credit shocks are especially relevant for firms exporting complex services to countries with weaker institutions and for services that are not the main product of the firms. Overall, our results suggest that credit supply plays a relevant role for exporting services during crises.     

Beta Regimes for the Yield Curve

We propose an affine term structure model which accommodatesnonlinearities in the drift and volatility function of the short-terminterest rate. Such nonlinearities are a consequence of discretebeta-distributed regime shifts constructed on multiple thresholds.We derive iterative closed-form formula for the whole yieldcurve dynamics that can be estimated using a linearized Kalmanfilter. Fitting the model on US data, we collect empirical evidenceof its potential in estimating conditional volatility and correlationacross yields.     

On the microstructure of price determination and information aggregation with sequential and asymmetric information arrival in an experimental asset market

Summary. Experiments were conducted on an asset with the structure of an option. The information of any individual is limited, as if only the direction of movement of the option value known for a single period without information of the value from when movement was initiated. However, if all information of all insiders were pooled, the value of the option would be known with certainty. The results are the following: (1) Information becomes aggregated in the prices as if fully informative rational expectations operated; and (2) The mechanism through which information gets into the market is captured by a path dependent process that we term The Fundamental Coordination Principle of Information Transfer in Competitive Markets. The early contracts tend to be initiated by insiders who tender limit orders. The emergence of bubbles and mirages in the markets are coincident with failures and circumstances that prevent the operation of the Fundamental Principle.The financial support of the national science foundation and the Caltech Laboratory for Experimental Economics and Political Science are gratefully acknowledged. The authors have benefited from helpful comments of David Grether, Kerry Back, Ivana Komunjer and Pete Kyle.     

Heterogeneous Agents in Public Goods Experiments

We explore by purely experimental means a heterogeneous agents scenario in experimental public goods games, assuming the existence of at least three types of player: free riders, cooperators, and reciprocators. We identify the various types by means of four classification methods, and then play the public goods game with homogeneous groups. We observe that (eq1) the average contribution level is enhanced in this setting; (2) the decay phenomenon is replicated in groups of pure free riders, whereas in groups of cooperative and reciprocating players the contribution is high and fairly stable throughout the game.The experiments reported in this paper were financed by the Cognitive Science Laboratory and the Computational and Experimental Economics Laboratory of the University of Trento. We would like to thank Marco Tecilla, Macrina Marchesin and Dino Parisi for their help in running the experiments, and Luigi Mittone, director of CEEL, for letting us use the laboratorys resources. Paul Webley, Robert Moir, seminar participants at the Universities of Pisa and Trento, Charles Holt and two anonymous referees provided very useful comments on a previous draft.     

On the scope of experiments in economics: comments on Siakantaris

The problem of ‘parallelism’ or external validitycan in principle be solved; I try to show how by means of twosimple examples. I also criticise attempts to dismiss experimentaleconomics that appeal to alleged ontological differences betweenthe natural and the social realm.     

Unemployment, growth and taxation in industrial countries

To the layman, the upward trend in European unemployment is related to the slowdown of economic growth. We argue that the layman's view is correct. The increase in European unemployment and the slowdown in economic growth are related, because they stem from a common cause: an excessively rapid growth in the cost of labour. In Europe, labour costs have gone up for many reasons, but one is particularly easy to identify: higher taxes on labour. If wages are set by strong and decentralized trade unions, an increase in labour taxes is shifted onto higher real wages. This has two effects. First, it reduces labour demand, and thus creates unemployment. Secondly, as firms substitute capital for labour, the marginal product of capital falls; over long periods of time, this in turn diminishes the incentive to invest and to grow. The data strongly support this view. According to our estimates, the observed rise of 14 percentage points in labour tax rates between 1965 and 1995 in the EU could account for a rise in EU unemployment of roughly 4 percentage points, a reduction of the investment share of output of about 3 percentage points, and a growth slowdown of about 0.4 percentage points a year.