Dept. of Electrical and Electronic Engineering

Abstract A new global optimization algorithm for functions of continuous variables is presented, derived from the “Simulated Annealing” algorithm recently introduced in combinatorial optimization. The algorithm is essentially an iterative random search procedure with adaptive moves along the coordinate directions. It permits uphill moves under the control of a probabilistic criterion, thus tending to avoid the first local minima encountered.

We present a stochastic simulation model of a prototype financial market. Our market is populated by both noise traders and fundamentalist speculators. The dynamics covers switches in the prevailing mood among noise traders (optimistic or pessimistic) as well as switches of agents between the noise trader and fundamentalist group in response to observed differences in profits. The particular behavioral variant adopted by an agent also determines his decision to enter on the long or short side of the market.

Abstract The authors describe the salient features of using a simulated annealing (SA) algorithm in the context of designing digital filters with coefficient values expressed as the sum of power of two. A procedure for linear phase digital filter design, using this algorithm, is presented and tested, yielding results as good as those for known optimal methods.

Can research projects be agile? In this paper we describe our proposal of applying Scrum for the management of an European research project aimed at developing an agent-based software platform for European economic policy design. The use of an agile, adaptive methodology is justified because successful research projects are complex, unstable processes, that should be continuously adapted along their way. We describe in detail the roles, artifacts and practices of the proposed process, and the first steps of its adoption.

The Tobin tax is a solution proposed by many economists for limiting the speculation in foreign exchange and stock markets and for making these markets stabler. In this paper we present a study on the effects of a transaction tax on one and on two related markets, using an artificial financial market based on heterogeneous agents. The microstructure of the market is composed of four kinds of traders: random traders, fundamentalists, momentum traders and contrarians, and the resources allocated to them are limited.

Abstract In this paper, an artificial financial market based on heterogeneous agents is presented. The proposed market is composed of traders with limited amount of cash, one traded asset and a centralized mechanism, the market maker, matching buy and sell orders. The price formation process is given by the intersection of the demand and the supply curve.

ABSTRACT Pair programming is one of the most controversial parts of XP. Claims are mostly based on anecdotal evidence and limited experimentation performed in classroom settings. This paper reports the preliminary results of an analysis of the effects of pair programming on job satisfaction. A questionnaire on pair programming techniques has been compiled and posted on the web. 108 responses have been collected from around the world. The preliminary results evidence a very positive effect of pair programming on job satisfaction.

Abstract Neural networks are becoming a very useful tool for the processing of data in several communication applications, where it is of great interest to have complex computing structures. In this paper, after a brief review of existing techniques, a new complex Multi-Layer Perceptron is proposed. In particular, after defining a proper neuron structure (ie using a nonanalytic activation function), a novel learning algorithm is derived.

In this paper we show how agile practices have been used at the Poste Italiane for building a monitoring system of its complex IT infrastructure. The system, called Datamart, is built upon the existing monitoring infrastructure. A testing framework has been developed for performing assertion checking either on existing legacy modules or on the new functionalities. This framework is currently used, and is able to process data coming from 100,000 distributed computers, enabling and improving their centralized control.

Abstract We study the application to object-oriented software of new metrics, derived from Social Network Analysis. Social Networks metrics, as for instance, the EGO metrics, allow to identify the role of each single node in the information flow through the network, being related to software modules and their dependencies. These metrics are compared with other traditional software metrics, like the Chidamber-Kemerer suite, and software graph metrics.

This paper presents a neural network system for the diagnosis of analog circuits and shows how the performance of such a system can be affected by the choice of different techniques used by its submodules. In particular we discuss the influence of feature extraction techniques such as Fourier Transforms, Wavelets and Principal Component Analysis. The system uses several different power supplies and as many neural networks “in parallel”.

Team work is defined by different factors: team size, members role, interactions and communication. In Agile Methodologies communication plays a fundamental role. Some research studies have found that the involvement of team members in a project also depends on the information provided. Communication also depends on the tool employed. The aim of this paper is to analyze communication among team members of the 9 most active projects on Sourceforge provided of a developers' mailing list.

To maintain a good voltage quality level to customers in power distribution system, it is essential to minimise transients, line voltage dips and spikes due to a variety of causes, including fault occurrence, power interruption and large load changes. In case of private generating systems it is essential that ultra-rapid switching devices be used which cut off the customer plant from the utility system so quickly that the presence of voltage dips is not perceived by the industrial plant's sensitive loads.

Abstract Since" design-oriented" life-cycles came to their maturity, dramatic changes have been introduced as far as programming tools and computer hardware are concerned. Such changes made it possible to develop applications focusing on refactoring rather than on analysis and design. The underlying hypothesis is that by adopting suitable tools and target languages, refactoring would possibly cost less than the overhead introduced by modern A& D techniques.

In this paper, we present an extension of the Genoa artificial stock market (GASM)(Raberto et al., 2001) that includes a limit order book as mechanism for price formation. At every time step an agent is chosen with uniform distribution to issue an order. The order can be a limit order or a market order. If the order is a limit order, it is stored in the book; if the order is a market order, a transaction occurs. Prices are formed at variable time steps, ie, only when a market order is issued.

Abstract In this paper we present the aims and the activities which are being carried on in the context of TOSSAD project, to help developing an Open Source Curriculum. TOSSAD (Towards Open Source Software Adoption and Dissemination) is a Coordination Action funded in the context of 6th EU Framework Programme.

Abstract When multilayer neural networks are implemented with digital hardware, which allows full exploitation of the well developed digital VLSI technologies, the multiply operations in each neuron between the weights and the inputs can create a bottleneck in the system, because the digital multipliers are very demanding in terms of time or chip area. For this reason, the use of weights constrained to be power-of-two has been proposed in the paper to reduce the computational requirements of the networks.

This work was supported by the European Union through its 6th Framework Programme, FET-IST'Complex Systems'. Funding for the STREP research project 'EURACE'under contract no. 035086, is gratefully acknowledged. The following persons have contributed to this paper. Simon Coakley contributed to Section 2, Michele Marchesi contributed Section 4.2, Marco Raberto and Andrea Teglio contributed Section 4.3, and Herbert Dawid, Michael Neugart and collegues contributed Section 4.4.

In October, 1999, Kent Beck's book “Extreme Programming Explained—Embrace Change” was published. Well, you may love or hate XP, but for sure you cannot say it was irrelevant. By publishing his book, sold in hundreds of thousand copies and translated in tens of languages, Beck started the tidal wave of agile methodologies. These methodologies can be fully adopted, partially adopted or not adopted at all, but no serious software engineer may overlook them.