Dynamical selection of Nash equilibria using Experience Weighted Attraction Learning: emergence of heterogeneous mixed equilibria

We study the distribution of strategies in a large game that models how agents choose among different double auction markets. We classify the possible mean field Nash equilibria, which include potentially segregated states where an agent population can split into subpopulations adopting different strategies. As the game is aggregative, the actual equilibrium strategy distributions remain undetermined, however. We therefore compare with the results of Experience-Weighted Attraction (EWA) learning, which at long times leads to Nash equilibria in the appropriate limits of large intensity of choice, low noise (long agent memory) and perfect imputation of missing scores (fictitious play). The learning dynamics breaks the indeterminacy of the Nash equilibria. Non-trivially, depending on how the relevant limits are taken, more than one type of equilibrium can be selected. These include the standard homogeneous mixed and heterogeneous pure states, but also \emph{heterogeneous mixed} states where different agents play different strategies that are not all pure. The analysis of the EWA learning involves Fokker-Planck modeling combined with large deviation methods. The theoretical results are confirmed by multi-agent simulations.Comment: 35 pages, 16 figure

Information transfer by quantum matterwave modulation

Classical communication schemes that exploit wave modulation are the basis of the information era. The transfer of information based on the quantum properties of photons revolutionized these modern communication techniques. Here we demonstrate that also matterwaves can be applied for information transfer and that their quantum nature provides a high level of security. Our technique allows transmitting a message by a non-trivial modulation of an electron matterwave in a biprism interferometer. The data is encoded by a Wien filter introducing a longitudinal shift between separated matterwave packets. The transmission receiver is a delay line detector performing a dynamic contrast analysis of the fringe pattern. Our method relies on the Aharonov-Bohm effect and has no light optical analog since it does not shift the phase of the electron interference. A passive eavesdropping attack will cause decoherence and terminating the data transfer. This is demonstrated by introducing a semiconducting surface that disturbs the quantum state by Coulomb interaction and reduces the contrast. We also present a key distribution protocol based on the quantum nature of the matterwaves that can reveal active eavesdropping

Terrorism in the Sinai

This report tracks and analyzes militant activity in the Sinai Peninsula. It focuses on the violence that has occurred since 2011, and particularly on the major increase in violence has been ongoing since July 2013. The project relies on open source intelligence to identify the reasons for the increase in violence and also determine the nature of the violence – who is carrying out the attacks and why. On July 3, 2013, the Egyptian military removed the democratically elected President Mohamed Morsi. What followed was an unprecedented increase in violence in the Sinai Peninsula. Since the fall of 2013, the violence has spread from the Sinai Peninsula into the mainland of Egypt. Hundreds of security personnel have been killed or injured since the uptick in the violence. After the coup that removed Morsi, there was a significant shift in the targets of attacks and the tactics used and this shift is indicative of the presence of the global jihadi network in the Sinai. Terrorist groups stopped targeting Israel and turned almost exclusively to Egypt security personnel. There has also been a major increase in suicide attacks, which indicates that there is a connection between the global jihadi network and Egyptian militant groups. The military is once again in control of Egypt’s government yet they have focused on consolidating political control instead of dealing with Egypt’s mounting security problem. The military has consistently insisted that the Muslim Brotherhood is behind the terror and ignored the true cause of the violence. This willful omission has allowed the terrorist groups in the Sinai to flourish and threaten security in mainland Egypt.Middle Eastern StudiesGlobal Policy Studie

Exploring the Relationship between Silencing the Self and Risky Sexual Behavior in Black Women

Black women are disproportionately affected by HIV. Understanding how sociocultural factors and beliefs contribute to Black women\u27s risky sexual behavior is critical in understanding this health disparity. This study investigated the mediating influence of silencing the self (i.e., putting the needs and wants of a romantic partner before one\u27s own needs) on the relationship between risky sexual behaviors and self-esteem, gender role beliefs, and gender ratio imbalance beliefs and behaviors (GRIBBs) in Black female college students. Participants included 99 female undergraduate students enrolled at a regional Mid-South University. Results demonstrated that risky sexual behavior was not significantly associated wtih the hypothesized variables. Higher scores on silencing the self was significantly associated with lower self-esteem (b =-1.42, p \u3c .001) and higher GRIBBS (b = .82, p \u3e .001). The results suggest that silencing the self can still adversely impact Black women, despite its non-significant relationship with risky sex

Tv-RIO1 – an atypical protein kinase from the parasitic nematode Trichostrongylus vitrinus

Background: Protein kinases are key enzymes that regulate a wide range of cellular processes, including cell-cycle progression, transcription, DNA replication and metabolic functions. These enzymes catalyse the transfer of phosphates to serine, threonine and tyrosine residues, thus playing functional roles in reversible protein phosphorylation. There are two main groups, namely eukaryotic protein kinases (ePKs) and atypical protein kinases (aPKs); RIO kinases belong to the latter group. While there is some information about RIO kinases and their roles in animals, nothing is known about them in parasites. This is the first study to characterise a RIO1 kinase from any parasite. Results: A full-length cDNA (Tv-rio-1) encoding a RIO1 protein kinase (Tv-RIO1) was isolated from the economically important parasitic nematode Trichostrongylus vitrinus (Order Strongylida). The uninterrupted open reading frame (ORF) of 1476 nucleotides encoded a protein of 491 amino acids, containing the characteristic RIO1 motif LVHADLSEYNTL. Tv-rio-1 was transcribed at the highest level in the third-stage larva (L3), and a higher level in adult females than in males. Comparison with homologues from other organisms showed that protein Tv-RIO1 had significant homology to related proteins from a range of metazoans and plants. Amino acid sequence identity was most pronounced in the ATP-binding motif, active site and metal binding loop. Phylogenetic analyses of selected amino acid sequence data revealed Tv-RIO1 to be most closely related to the proteins in the species of Caenorhabditis. A structural model of Tv-RIO1 was constructed and compared with the published crystal structure of RIO1 of Archaeoglobus fulgidus (Af-Rio1). Conclusion: This study provides the first insights into the RIO1 protein kinases of nematodes, and a foundation for further investigations into the biochemical and functional roles of this molecule in biological processes in parasitic nematodes

Supporting People with Vision Impairments in Automated Vehicles: Challenge and Opportunities

Autonomous and automated vehicles (AVs) will provide many opportunities for mobility and independence for peoplewith vision impairments (PwVI). This project provides insights on the challenges and potential barriers to their adoptionof AVs. We examine adoption and use of ridesharing services. We study ridesharing as a proxy for AVs as they are asimilar means of single-rider transportation for PwVI through observations and interviews. We also investigateperceptions towards autonomous vehicles and prototypes to address perceived barriers to AV use through design focusgroups with blind and low vision people. From these studies, we provide recommendations to AV manufacturers andsuppliers for how to best design vehicles and interactive systems that people with vision impairments trust.United States Department of Transportationhttps://deepblue.lib.umich.edu/bitstream/2027.42/156054/3/Supporting People with Vision Impairments in Automated Vehicles - Challenges and Opportunities.pd

A joint stock and bond market based on the hyperbolic Gaussian model

In this paper, we introduce a joint bond and stock market model based on the state price density approach as a mean to discount future payments - whether these are stochastic dividend payments or secure repayments of government zerobonds. Based upon a recipe of Rogers (1997), we define a state price density model, the so-called Hyperbolic Gaussian model which allows for closed form zerobond prices and stock prices in an arbitrage-free way. It is particularly useful for insurance applications where large time horizons are considered. We estimate the joint factor model using the extended Kalman filter. The model we propose here is computationally much simpler than other models which have been considered in the literature

Stochastic evolution in populations of ideas

It is known that learning of players who interact in a repeated game can be interpreted as an evolutionary process in a population of ideas. These analogies have so far mostly been established in deterministic models, and memory loss in learning has been seen to act similarly to mutation in evolution. We here propose a representation of reinforcement learning as a stochastic process in finite "populations of ideas". The resulting birth-death dynamics has absorbing states and allows for the extinction or fixation of ideas, marking a key difference to mutation-selection processes in finite populations. We characterize the outcome of evolution in populations of ideas for several classes of symmetric and asymmetric games.Comment: 37 pages, 20 figure