46 research outputs found
Citation Counts and Evaluation of Researchers in the Internet Age
Bibliometric measures derived from citation counts are increasingly being
used as a research evaluation tool. Their strengths and weaknesses have been
widely analyzed in the literature and are often subject of vigorous debate. We
believe there are a few fundamental issues related to the impact of the web
that are not taken into account with the importance they deserve. We focus on
evaluation of researchers, but several of our arguments may be applied also to
evaluation of research institutions as well as of journals and conferences.Comment: 4 pages, 2 figures, 3 table
Unveiling evolutionary algorithm representation with DU maps
Evolutionary algorithms (EAs) have proven to be effective in tackling problems in many different domains. However, users are often required to spend a significant amount of effort in fine-tuning the EA parameters in order to make the algorithm work. In principle, visualization tools may be of great help in this laborious task, but current visualization tools are either EA-specific, and hence hardly available to all users, or too general to convey detailed information. In this work, we study the Diversity and Usage map (DU map), a compact visualization for analyzing a key component of every EA, the representation of solutions. In a single heat map, the DU map visualizes for entire runs how diverse the genotype is across the population and to which degree each gene in the genotype contributes to the solution. We demonstrate the generality of the DU map concept by applying it to six EAs that use different representations (bit and integer strings, trees, ensembles of trees, and neural networks). We present the results of an online user study about the usability of the DU map which confirm the suitability of the proposed tool and provide important insights on our design choices. By providing a visualization tool that can be easily tailored by specifying the diversity (D) and usage (U) functions, the DU map aims at being a powerful analysis tool for EAs practitioners, making EAs more transparent and hence lowering the barrier for their use
How Phishing Pages Look Like?
Recent phishing campaigns are increasingly targeted to specific, small population of users and last for increasingly shorter life spans. There is thus an urgent need for developing defense mechanisms that do not rely on any forms of blacklisting or reputation: there is simply no time for detecting novel phishing campaigns and notify all interested organizations quickly enough. Such mechanisms should be close to browsers and based solely on the visual appearance of the rendered page. One of the major impediments to research in this area is the lack of systematic knowledge about how phishing pages actually look like.
In this work we describe the technical challenges in collecting a large and diverse collection of screenshots of phishing pages and propose practical solutions. We also analyze systematically the visual similarity between phishing pages and pages of targeted organizations, from the point of view of a similarity metric that has been proposed as a foundation for visual phishing detection and from the point of view of a human operator
A Security-Oriented Analysis of Web Inclusions in the Italian Public Administration
Modern web sites serve content that browsers fetch automatically from a number of different web servers that may be placed anywhere in the world. Such content is essential for defining the appearance and behavior of a web site and is thus a potential target for attacks. Many public administrations offer services on the web, thus we have entered a world in which web sites of public interest are continuously and systematically depending on web servers that may be located anywhere in the world and are potentially under control of other governments. In this work we focus on these issues by investigating the content included by almost 10.000 web sites of the Italian Public Administration. We analyze the nature of such content, its quantity, its geographical location, the amount of dynamic variations over time. Our analyses demonstrate that the perimeter of trust of the Italian Public Administration collectively includes countries that are well beyond the control of the Italian government and provides several insights useful for implementing a centralized monitoring service aimed at detecting anomalies
Biodiversity in evolved voxel-based soft robots
In many natural environments, there are different forms of living creatures that successfully accomplish the same task while being diverse in shape and behavior. This biodiversity is what made life capable of adapting to disrupting changes. Being able to reproduce biodiversity in non-biological agents, while still optimizing them for a particular task, might increase their applicability to scenarios where human response to unexpected changes is not possible. In this work, we focus on Voxel-based Soft Robots (VSRs), a form of robots that grants great freedom in the design of both body and controller and is hence promising in terms of biodiversity. We use evolutionary computation for optimizing, at the same time, body and controller of VSRs for the task of locomotion. We investigate experimentally whether two key factors - -evolutionary algorithm (EA) and representation - -impact the emergence of biodiversity and if this occurs at the expense of effectiveness. We devise a way for measuring biodiversity, systematically characterizing the robots shape and behavior, and apply it to the VSRs evolved with three EAs and two representations. The experimental results suggest that the representation matters more than the EA and that there is not a clear trade-off between diversity and effectiveness
Crowded Environment Navigation with NEAT: Impact of Perception Resolution on Controller Optimization
Crowd navigation with autonomous systems is a topic which has seen a rapid increase in interest recently. While it appears natural to humans, being able to reach a target can prove difficult or impossible to a mobile robot because of the safety issues related to collisions with people. In this work we propose an approach to control a robot in a crowded environment; the method employs an Artificial Neural Network (ANN) that is trained with the NeuroEvolution of Augmented Topologies (NEAT) method. Models for the kinematics, perception, and cognition of the robot are presented. In particular, perception is based on a raycasting model which is tailored on the ANN. An in-depth analysis of a number of parameters of the environment and the robot is performed and a comparative analysis is presented; finally, results of the performance of the controller trained with NEAT are compared to those of a human driver who takes over the controller itself. Results show that the intelligent controller is able to perform on par with the human, within the simulated environment
Bibliometric Evaluation of Researchers in the Internet Age
Research evaluation, which is an increasingly pressing issue, invariably relies on citation counts. In this contribution we highlight two concerns that the research community needs to pay attention to. One, in the world of search engine facilitated research, factors such as ease of web discovery, ease of access, and content relevance rather than quality influence what gets read and cited. Two, research evaluation based on citation counts works against many types of high-quality works. We will also elaborate on the implications of these points by examining a recent nation-wide evaluation of researchers performed in Italy. We focus on our discipline (computer science), but we believe that our observations have relevance for a broad audience
On the Effects of Learning Set Corruption in Anomaly-based Detection of Web Defacements
Anomaly detection is a commonly used approach for constructing intrusion detection systems. A key requirement is that the data used for building the resource profile are indeed attack-free, but this issue is often skipped or taken for granted. In this work we consider the problem of corruption in the learning data, with respect to a specific detection system, i.e., a web site integrity checker. We used corrupted learning sets and observed their impact on performance (in terms of false positives and false negatives). This analysis enabled us to gain important insights into this rather unexplored issue. Based on this analysis we also present a procedure for detecting whether a learning set is corrupted. We evaluated the performance of our proposal and obtained very good results up to a corruption rate close to 50%. Our experiments are based on collections of real data and consider three different flavors of anomaly detection
Detection of Hidden Fraudulent URLs within Trusted Sites using Lexical Features
Internet security threats often involve the fraudulent modification of a web site, often with the addition of new pages at URLs where no page should exist. Detecting the existence of such hidden URLs is very difficult because they do not appear during normal navigation and usually are not indexed by search engines.
Most importantly, drive-by attacks leading users to hidden URLs, for example for phishing credentials, may fool even tech-savvy users, because such hidden URLs are increasingly hosted within trusted sites, thereby rendering HTTPS authentication ineffective.
In this work, we propose an approach for detecting such URLs based only on their lexical features, which allows alerting the user before actually fetching the page. We assess our proposal on a dataset composed of thousands of URLs, with promising results
A Look at Hidden Web Pages in Italian Public Administrations
Preventing illegitimate modifications to web sites offering a public service is a fundamental requirement of any e-government initiative. Unfortunately, attacks to web sites resulting in the creation of fraudulent content by hackers are ubiquitous. In this work we attempted to assess the ability of Italian public administrations to be in full control of the respective web sites. We examined several thousands sites, including all local governments and universities, and found that approximately 1.16% of the analyzed sites serves contents that admittedly is not supposed to be there. Although these contents do not constitute an immediate threat to citizens, this result does not seem very encouraging also because our methodology leads to very conservative estimates. We believe that our analysis allows gaining useful insights into this novel and peculiar threat