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In this paper we present a study on micro patterns in different releases of two software systems developed with Object Oriented technologies and Agile process. Micro patterns are design decisions in code that can be easily automatically recognised. Gil and Maman introduced the concept to support providing objective assessment of design decisions [1]. They catalogued 27 micro patterns that capture a variety of programming practices in Java. Micro patterns can be a useful metrics in order to measure the quality of software by showing that certain categories of micro patterns are more fault prone than others, and that the classes that do not correspond to any category of micro patterns are more likely to be faulty. In our study we present some empirical results on two case studies of systems developed with Agile methodologies, and compare them to previous results obtained for non Agile systems. In particular we have verified that the distribution of micro patterns in a software system developed using Agile methodologies does not differ from the distribution studied in other systems, and that the micro patterns fault-proneness is about the same. We also analyzed how the distribution of micro patterns changes in different releases of the same software system. We demonstrate that there is a relationship between the number of faults and the classes that do not match with any micro patterns. We found that these classes are more likely to be fault-prone than the others even in software developed with Agile methodologies.

Nowadays, Scrum is the most used Agile Methodology, while the Lean-Kanban approach is perhaps the fastest growing AM. On the other hand, traditional, waterfall-like approaches are still very used in real-life software projects, due to the ease of up-front planning and budgeting, that however are seldom matched upon project completion. In our opinion, more effort is needed to study and model the inner structure and behavior of these approaches, highlighting positive and negative feedback loops that are strategic to understand their features, and to decide on their adoption. In this paper we analyze the dynamic behavior of the adoption of Kanban and Scrum, versus a traditional software development process such as the Waterfall approach. We use a system dynamics model, based on the relationships between system variables, to assess the relative benefits of the studied approaches. The model is simulated using a commercial tool. The proposed model visualizes the relationships among these software development processes, and can be used to study their relative advantages and disadvantages.

We developed an event-driven simulator of the Kanban process a WIP limited pull system visualized by the Kanban board. WIP (work in process) represent the capacity in the activity to perform features simoultaneously. The simulator is fully object-oriented, and its design model reflects the objects of the Lean software development domain. We used this simulator to assess comparatively WIP-limited and unlimited processes. We also studied the optimum values of the working item limits in the activities, using a paradigmatic case of 4 activities and 100 work items. The cost function used is equal to the total time needed to complete the project, plus a weighted sum of the limits themselves. We performed an exhaustive search on all the admissible values of the solution, finding sensible optimal values, and a non-trivial behavior of the cost function in the optimization space.

In recent years, a very important structural change in the software industry took place, with an increasing number of firms that got involved in Free/Libre Open Source Software (FLOSS) development communities. FLOSS communities and products have been studied as complementary to proprietary software companies and products. In this paper we propone a business model for the software market, and in particular we analyze the competition between proprietary software firms and FLOSS firms. Our software market is a system where each agent is independent of each other in the choice about buying or selling software products or services. The proposed work aims to analyze the influence of FLOSS firms producing both software and services in vertical software markets, nowadays mostly dominated by large proprietary firms. The findings show that FLOSS firms are able to compete with proprietary firms, though in the end a monopoly or oligopoly of the latters emerges. The ousted FLOSS firms, however, survive longer than proprietary ones, when these are not able to compete in the market.

We suggest that we need a fundamentally different philosophy and a concept for how organisations are led and managed. We believe that it is time to challenge the traditional management myths. The main goal of Beyond Budget- ing is not get rid of budgets. The budget must go, but it is more the budgeting mindset we need to get rid of, because it represents the old thinking that needs to be changed. Based on the works of The Beyond Budgeting Round Table, we review a set of 12 principles for a new style of contemporary leadership and management.

We present an agile process used for the development of a Web application written in Java, devised by choosing a set of proven agile practices taken by existing popular agile methodologies. During the project, we regularly measured the software using Chidamber and Kemerer object-oriented metrics suite, and other metrics. The application development evolved through phases, characterized by a different level of adoption of some key agile practices --- such as pair programming, test-based development and refactoring. The evolution of the OO metrics of the system, and their behavior related to the agile practices adoption level is presented and discussed, showing that soft ware quality, as measured using standard OO metrics, looks directly related to agile practices adoption.

The development of a Web application using agile practices is presented, characterized by empirical software measurements that have been performed throughout the duration of the project. The project is the specialization of jAPS, an open source Java Web portal generation framework, for building a Research Register management system. The agile principles and practices used in the project are described and discussed. During the various phases of the project some key agile practices, such as pair programming, test-based development and refactoring, were used at different levels of adoption. The evolution of some object-oriented metrics of the system, and their behavior related to the agile practices adoption level is presented and discussed, showing that software quality, as measured using standard OO metrics, looks directly related to agile practices adoption.

In the past thirty years, options have become an important financial instrument, and now they account for a substantial percentage of total trading activity. From a research perspective, a lot of research have been carried out about the theoretical computation of option prices, starting from the seminal works of Black and Scholes (1973) and Merton (1973). Several researchers also examined the issue of to which extent options interact with their underlying stocks, and in particular their possible effects on stock returns and volatility, and on the overall quality of the underlying security market.

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.

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 Source-forge provided of a developers' mailing list. In particular we tried to investigate how and why members post to developers' mailing list and the use that different members make of these mailing lists.

This paper analyzes the development of a project initiated by a co-located agile team that subsequently evolved into a distributed context. The project, named JAPS (Java Agile Portal System) [1], has been monitored on a regular basis since it started in January 2005, collecting both process and product metrics. Product metrics have been calculated by checking out the source code history from the CVS repository. By analyzing the evolution of these metrics, it has been possible to evaluate how the distribution of the team has impacted the source code quality.

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, i.e., only when a market order is issued. We investigate how the new asynchronous trading mechanism affects the statistical properties of simulated prices. This computational experiment shows that the fat tails of the returns distribution can be recovered simply as a consequence of the limit order book without any additional assumption on agents' behavior.

We present XPSwiki, a tool supporting the XP practices for requirement gathering and project management - user stories and the Planning Game. XPSwiki has been developed in Smalltalk using Squeak Swiki technology. It is accessed through the Internet in a user friendly agile way. XPSwiki keeps track of multiple projects, each with its releases, iterations, user stories, acceptance tests, and engineering tasks. It also manages teams of developers, who sign stories and tasks, and who pair-program them with another team member. XPSwiki allows project tracking and documentation, and is at present in use among real software firms.

We present the development of XPSwiki, a tool supporting the XP practices for requirement gathering and project management – user stories and the Planning Game. XPSwiki has been developed in Smalltalk using Squeak Swiki technology, and is accessed through the Internet in a user friendly, agile way. It keeps track of multiple projects, each with its releases, iterations, user stories, acceptance tests, and tasks. XPSwiki allows project tracking, and automates documentation generation and metrics collection. It is presently in use in real software development environments.

This paper presents an artificial financial market based on heterogeneous agents which are endowed with a limited amount of cash and one traded asset. Agents make random buy and sell decisions which are constrained by their limited resources and depend on the past price volatility. The price formation process is given by the intersection of the supply and demand curves.

This paper proposes an extension of the inventory production model developed in Bak, Chen, Scheinkman, and Woodford (BCSW, 1993). We show how the Pareto-Levy type of aggregate distributions emerge in global models as well as in local models. We extend the BCSW model by allowing random connections between firms. The distribution of production in the economy follows a power law probability distribution. In addition, the long-run frequency distribution follows the same law.