The Use of Welfare by Migrants in Italy

A large part of the Italian welfare system is designed and implemented at the very local level, leading to a high degree of heterogeneity in the type and the generosity of available programs across the country. As a consequence, studies of welfare use based on standard household surveys may fail to consider a large part of welfare recipients and provisions. In this paper I overcome such a problem by combining the analysis of welfare use in the Italian sample of the European Survey of Incomes and Living Conditions (EU-SILC) with theinvestigation of a new administrative archive that contains information on means tests certificates needed for applying to all kind of locally administered welfare programs. Results show that, without controlling for observable characteristics, migrants from outside the EU are more likely to receive or apply for welfare. Once individual and household characteristics are controlled for, such a residual welfare dependency is greatly reduced but does not disappear Geographical location is a key factor, given that migrants tend to locate in therichest areas of the country, which also happen to be the ones where the local welfare is most generous

Static Hedging of Multivariate Derivatives by Simulation

We propose an approximate static hedging procedure for multivariate derivatives. The hedging portfolio is composed of statically held simple univariate options, optimally weighted minimizing the variance of the difference between the target claim and the approximate replicating portfolio. The method uses simulated paths to estimate the weights of the hedging portfolio and is related to Monte Carlo control variates techniques. We report numerical results showing the performance of this static hedging procedure on bivariate options on the maximum of two assets and on 2- and 7-dimensional portfolio options. It is shown that, in the presence of transaction costs, Value at Risk and Expected Shortfall of the dynamically hedged positions can be higher than the ones obtained by a static hedge.Monte Carlo methods, option pricing, static and dynamic hedging

The Use of Welfare by Migrants in Italy

A large part of the Italian welfare system is designed and implemented at the very local level, leading to a high degree of heterogeneity in the type and the generosity of available programs across the country. As a consequence, studies of welfare use based on standard household surveys may fail to consider a large part of welfare recipients and provisions. In this paper I overcome such a problem by combining the analysis of welfare use in the Italian sample of the European Survey of Incomes and Living Conditions (EU-SILC) with the investigation of a new administrative archive that contains information on means tests certificates needed for applying to all kind of locally administered welfare programs. Results show that, without controlling for observable characteristics, migrants from outside the EU are more likely to receive or apply for welfare. Once individual and household characteristics are controlled for, such a residual welfare dependency is greatly reduced but does not disappear. Geographical location is a key factor, given that migrants tend to locate in the richest areas of the country, which also happen to be the ones where the local welfare is most generous.migration, welfare

The Toll of Subrational Trading in an Agent Based Economy

In an agent-based exchange economy, we measure the loss of wealth for rational agents due to the presence of varying proportions of subrational (boundedly rational) traders that do not know all the needed parameters. We consider two departures from rationality: M-traders use private, stochastic and unbiased signals to build an estimate of the value of the risky asset; chartists only use the last observed price. The exchange takes place using a realistic continuous double auction. We show by numerical simulations that M-traders’ subrational behavior does not reduce the wealth of the rational agents. On the contrary, a sizable fraction of chartists can lead to mispricing of the risky asset and to a reduction of the wealth share of the rational traders. Moreover, as chartists perceive a higher wealth than the others, due to wrong estimates of the fundamental value, their fraction in the market may not dissolve in the long run.risk sharing; boundedly rationality; cost of subrational trading; agent-based markets

Optimal trading in a limit order book using linear strategies.

We numerically determine the equilibrium trading strategies in a Continuous Double Auction (CDA). We consider heterogeneous and liquidity motivated agents, with private values and costs, that trade sequentially in random order under time constraints and are not aware of the type of the other agents in their session. We assume that they submit limit orders using a simple linear function of the current best quotes (ask and bid). In equilibrium, found using an Evolution Strategies algorithm, impatient agents do not always submit market orders, as in other models of CDAs, and agents take into account both sides of the book in their optimal decision. Finally, we provide a description of the price and of the ``small'' set of states of the equilibrium book.Continuous double auction, dynamic equilibrium, optimal trad- ing strategies, evolution strategies.

Zero-Intelligence Trading without Resampling

This paper studies the consequences of removing the resampling assumption from the zero-intelligence trading model in Gode and Sunder (1993). We obtain three results. First, individual rationality is no longer sufficient to attain allocative effciency in a continuous double auction; hence, the rules of the market matter. Second, the allocative effciency of the continuous double auction is higher than for other sequential protocols both with or without resampling. Third, compared to zero intelligence, the effect of learning on allocative effciency is sharply positive without resampling and mildly negative with resampling.

Utility based pricing of contingent claims

In a discrete setting, we develop a model for pricing a contingent claim. Since the presence of hedging opportunities influences the price of a contingent claim, first we introduce the optimal hedging strategy assuming a contingent claim has been issued: a strategy implemented by investing the budget plus the selling price is optimal if it maximizes the expected utility of the agent's revenue, which is the difference between the outcome of the hedging portfolio and the payoff of the claim. Next, we introduce the `reservation price' as a subjective valuation of a contingent claim. This is defined as the minimum price to be added to the initial budget that makes the issue of the claim more preferable than optimally investing in the available securities. We define the reservation price both for a short position (reservation selling price) and for a long position (reservation buying price) in the contingent claim. When the contingent claim is redundant, both the selling and the buying price collapse in the usual Arrow-Debreu price. We develop a numerical procedure to evaluate the reservation price and two applications are provided. Different utility functions are used and some qualitative properties of the reservation price are shown.Incomplete markets, reservation price, expected utility, optimization

Which market protocols facilitate fair trading?

We study the performance of four market protocols with regard to their ability to equitably distribute the gains from trade among two groups of participants in an exchange economy. We test the protocols by running (computerized) experiments. Assuming Walrasian tatonemment as benchmark, there is a clear-cut ranking from best to worst: batch auction, nondiscretionary dealership, the hybridization of a dealership and a continuous double auction, and finally the pure continuous double auction.allocative efficiency, allocative fairness, allocative neutrality, comparison of market institutions, market microstructure, performance criteria.

A Multi-Agent Model of Tax Evasion with Public Expenditure

We develop a model where heterogeneous agents maximize their individual utility based on (after tax) income and on the level of public expenditure (as in Cowell, Gordon, 1988). Agents are different in risk aversion and in the relative preference for public expenditure with respect to personal income. In each period, an agent can optimally conceal some income based on conjectures on the perceived probability of being subject to audits, the perceived level of public expenditure and the perceived amount of tax paid by other individuals. As far as the agent-based model is concerned, we assume that the Government sets the tax rate and the penalties, uses all the revenue to finance public expenditure (with no inefficiency) and fights evasion by controlling a (random) fraction of agents. We show that, through computational experiments based on micro-simulations, stable configurations of tax rates and public expenditure endogenously form in this case as well. In such equilibrium-like situations we find: • a positive relationship between the tax rate and evasion still arises. • tax compliance mainly depends on the distribution of personal features like risk-aversion and the degree of preference for public expenditure. • an endogenous level of tax evasion that is almost not affected by reasonable rates of control. A proper choice of the tax rate results instead in voluntary partial compliance. • the enforcement of higher compliance rates requires unrealistic and costly large-scale audits.Tax evasion, public expenditure, agent-based models

Some effects of transaction taxes under different microstructures

We show that the effectiveness of transaction taxes depends on the market microstructure. Within our model, heterogeneous traders use a blend of technical and fundamental trading strategies to determine their orders. In addition, they may become inactive if the profitability of trading decreases. We find that in a continuous double auction market the imposition of a transaction tax is not likely to stabilize financial markets since a reduction in market liquidity amplifies the average price impact of a given order. In a dealership market, however, abundant liquidity is provided by specialists, and thus a transaction tax may reduce volatility by crowding out speculative orders.Transaction tax, Tobin tax, microstructures, agent-based models, liquidity.