Inter-arrival times of message propagation on directed networks

One of the challenges in fighting cybercrime is to understand the dynamics of message propagation on botnets, networks of infected computers used to send viruses, unsolicited commercial emails (SPAM) or denial of service attacks. We map this problem to the propagation of multiple random walkers on directed networks and we evaluate the inter-arrival time distribution between successive walkers arriving at a target. We show that the temporal organization of this process, which models information propagation on unstructured peer to peer networks, has the same features as SPAM arriving to a single user. We study the behavior of the message inter-arrival time distribution on three different network topologies using two different rules for sending messages. In all networks the propagation is not a pure Poisson process. It shows universal features on Poissonian networks and a more complex behavior on scale free networks. Results open the possibility to indirectly learn about the process of sending messages on networks with unknown topologies, by studying inter-arrival times at any node of the network.Comment: 9 pages, 12 figure

Student Ensemble: Normal Community High School Women’s Chorale, Illinois State University Women’s Choir, Illinois State University Early Music Recorder Ensemble

Center for the Performing ArtsNovember 13, 2011Sunday Evening6:00 p.m

Design of a videogame to explore morality

A number of video games involve moral narratives or require the player to make moral decisions and research from psychologists has helped to understand the effects video game content can have on how individuals behave. Recent research has started to examine the role of morality in video games: however, there are many inconsistencies in the findings. We propose that some of these inconsistencies could be due to using commercial video games for research purposes, which contain biases such as familiarity with the game and favourite characters. The process of playing video games requires consideration of Human Computer Interaction (HCI); i.e., how the game is designed and then how it is received by the player. The aim of this poster is to highlight the work being conducted to design a game in order to investigate how moral decisions are made in video games. The design of video games usually draws on an understanding of HCI to produce play that is entertaining and engaging for the player. The game development process in this research draws on a fusion of psychology and HCI, and by drawing on theories of morality the design of the game will be grounded in psychology, as well as entertainment. Through fusing video game design principles, HCI and psychology, this work is novel in terms of a methodological as well as theoretical contribution to the area

Measurement of the weak mixing angle with the Drell-Yan process in proton-proton collisions at the LHC

This is the Pre-Print version of the Article - Copyright @ 2011 APSA multivariate likelihood method to measure electroweak couplings with the Drell-Yan process at the LHC is presented. The process is described by the dilepton rapidity, invariant mass, and decay angle distributions. The decay angle ambiguity due to the unknown assignment of the scattered constituent quark and antiquark to the two protons in a collision is resolved statistically using correlations between the observables. The method is applied to a sample of dimuon events from proton-proton collisions at sqrt(s) = 7 TeV collected by the CMS experiment at the LHC, corresponding to an integrated luminosity of 1.1 inverse femtobarns. From the dominant u-ubar, d-dbar to gamma*/Z to opposite sign dimuons process, the effective weak mixing angle parameter is measured to be sin^2(theta[eff]) = 0.2287 +/- 0.0020 (stat.) +/- 0.0025 (syst.). This result is consistent with measurements from other processes, as expected within the standard model