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Zero-sum asymmetric information games model decision-making scenarios involving two competing players who have different information about the game being played. A particular case is that of nested information, where one (informed) player has superior information over the other (uninformed) player. This paper considers the case of nested information in repeated zero-sum games and studies the computation of strategies for both the informed and uninformed players for finite-horizon and discounted infinite-horizon nested information games. For finite-horizon settings, we exploit that for both players, the security strategy, and also the opponent's corresponding best response, depend only on the informed player's history of actions. Using this property, we formulate an linear program (LP) computation of player strategies that is linear in the size of the uninformed player's action set. For the infinite-horizon discounted game, we construct LP formulations to compute the approximated security strategies for both players, and show that the worst-case performance difference between the approximated security strategies and the security strategies converges to zero exponentially. Finally, we illustrate the results on a network interdiction game between an informed system administrator and an uniformed intruder. [ABSTRACT FROM AUTHOR]

The article focuses on the database consisting of information of archive documents on the American Civil Liberties Union who defended the civil rights of the U.S. citizens.

The article discusses what the author refers to as the six most damaging computer hacking and security breach events involving law firms in the 21st century, including information about the Panama Papers leak involving more than 11 million documents from the Panama-based Mossack Fonseca & Co. legal company. Hacking events at the Cravath Swaine & Moore LLP, Weil Gotshal & Manges LLP, and Wiley Rein LLP law firms in 2012-2016 are examined, along with a Trojan horse computer virus.

This paper is concerned with the first passage discounted payoff criterion for continuous-time $N$ -person nonzero-sum stochastic games in countable states and Borel action spaces, where the discount factor is nonconstant. For the game with unbounded reward functions and transition rates, the optimality is over the set of all randomized history-dependent policies. After showing the uniqueness of the solution to the Shapley equation, we give some suitable conditions imposed on the primitive data for the existence of Nash equilibria. Then, a financial system is introduced to illustrate the applications of the main result here. [ABSTRACT FROM AUTHOR]

We consider both finite-horizon and infinite-horizon versions of a dynamic game with $N$ selfish players who observe their types privately and take actions that are publicly observed. Players’ types evolve as conditionally independent Markov processes, conditioned on their current actions. Their actions and types jointly determine their instantaneous rewards. In dynamic games with asymmetric information, a widely used concept of equilibrium is perfect Bayesian equilibrium (PBE) which consists of a strategy and belief pair that simultaneously satisfy sequential rationality and belief consistency. In general, there does not exist a universal algorithm that decouples the interdependence of strategies and beliefs over time in calculating PBE. In this paper, for the finite-horizon game with independent types, we develop a two-step backward–forward recursive algorithm that sequentially decomposes the problem (w.r.t. time) to obtain a subset of PBEs, which we refer to as structured Bayesian perfect equilibria (SPBE). In such equilibria, a player's strategy depends on his/her history only through a common public belief and its current private type. The backward recursive part of this algorithm defines an equilibrium generating function. Each period in the backward recursion involves solving a fixed-point equation on the space of probability simplexes for every possible belief on types. Using this function, equilibrium strategies and beliefs are generated through a forward recursion. We then extend this methodology to the infinite-horizon model, where we propose a time-invariant single-shot fixed-point equation, which in conjunction with a forward recursive step, generates the SPBE. Sufficient conditions for the existence of SPBE are provided. With our proposed method, we find equilibria that exhibit signaling behavior. This is illustrated with the help of a concrete public goods example. [ABSTRACT FROM AUTHOR]

In this paper, we consider a delay differential inclusion $\dot{x}(t)\in F(t,x_t)$ , where $x_t$ denotes the history function of $x(\cdot)$ along an interval of time. We extend the celebrated Filippov's theorem to this case. Then, we further generalize this theorem to the case when the state variable $x$ is constrained to the closure of an open subset $K\subset \mathbb {R}^n$. Under a new “inward pointing condition,” we give a relaxation result stating that the set of trajectories lying in the interior of the state constraint is dense in the set of constrained trajectories of the convexified inclusion ${\dot{x}(t)\in \mbox{co}\,F(t,x_t)}$. [ABSTRACT FROM AUTHOR]

The article discusses the history of the House of Commons in Great Britain, focusing on members Rhodes Boyson and Gwnfor Evans, who wrote so-called Black Paper policy statements for their political parties when in opposition in the 1960s and 1970s.

The article discusses the history of cancer treatment using combination chemotherapy and the discovery of alkaloid hemotherapeutic agents. In 1942, Yale pharmacologist Alfred Gilman worked on developing antidotes to nerve gases and other chemical weapons, and noticed that mustard gas caused a regression of cancer in rodents. Jane C. Wright, an African-American surgeon, reported in her paper that she had extended the success of methotrexate from blood to solid cancers.

Information Sciences is a leading international journal in computer science launched in 1968, so becoming fifty years old in 2018. In order to celebrate its anniversary, this study presents a bibliometric overview of the leading publication and citation trends occurring in the journal. The aim of the work is to identify the most relevant authors, institutions, countries, and analyze their evolution through time. The paper uses the Web of Science Core Collection in order to search for the bibliographic information. Our study also develops a graphical mapping of the bibliometric material by using the visualization of similarities (VOS) viewer. With this software, the work analyzes bibliographic coupling, citation and co-citation analysis, co-authorship, and co-occurrence of keywords. The results underline the significant growth of the journal through time and its international diversity having publications from countries all over the world. [ABSTRACT FROM AUTHOR]

The last decade in Malawi has been one characterized by a rise in the number of resuscitated ethnic groups. For instance, the Ngoni, the Chewa, and the Yao all seem to have regrouped to revive their common ethnic identities. One other ethnic group that has followed a similar route and suddenly risen to a position of prominence is that of the Lomwe, commonly found in Southern Malawi. Such a rise to prominence has seen the group form an organization called Mulhako wa Alomwe and indeed construct its own national headquarters in Mulanje District. This paper thus discusses factors that had for long time hindered the Lomwe's rise to a position of prominence and also those that have shaped and consolidated the ethnic group to express its ethnic consciousness in the manner it has done. The paper argues that the contemporary Lomwe atavism has largely been driven by material rather than merely common historical forces. [ABSTRACT FROM AUTHOR]

The article previews the web site new Founders Online from the U.S. National Archives and Records Administration (NARA).

Modeling and prediction of temporal sequences is central to many signal processing and machine learning applications. Prediction based on sequence history is typically performed using parametric models, such as fixed-order Markov chains ( $n$ -grams), approximations of high-order Markov processes, such as mixed-order Markov models or mixtures of lagged bigram models, or with other machine learning techniques. This paper presents a method for sequence prediction based on sparse hyperdimensional coding of the sequence structure and describes how higher order temporal structures can be utilized in sparse coding in a balanced manner. The method is purely incremental, allowing real-time online learning and prediction with limited computational resources. Experiments with prediction of mobile phone use patterns, including the prediction of the next launched application, the next GPS location of the user, and the next artist played with the phone media player, reveal that the proposed method is able to capture the relevant variable-order structure from the sequences. In comparison with the $n$ -grams and the mixed-order Markov models, the sparse hyperdimensional predictor clearly outperforms its peers in terms of unweighted average recall and achieves an equal level of weighted average recall as the mixed-order Markov chain but without the batch training of the mixed-order model. [ABSTRACT FROM AUTHOR]

Announces the 1997 Winterthur Conference's invitation for proposals for research papers that will assess the influence of race and ethnicity as formative factors in American material life from the 17th to the 19th centuries. Potential themes; Deadline.

Unveiling 30-year-old Cabinet papers have provided a fascinating glimpse behind the secrecy drawn over the deliberations of a generation-old government.

A language model (LM) is calculated as the probability of a word sequence that provides the solution to word prediction for a variety of information systems. A recurrent neural network (RNN) is powerful to learn the large-span dynamics of a word sequence in the continuous space. However, the training of the RNN-LM is an ill-posed problem because of too many parameters from a large dictionary size and a high-dimensional hidden layer. This paper presents a Bayesian approach to regularize the RNN-LM and apply it for continuous speech recognition. We aim to penalize the too complicated RNN-LM by compensating for the uncertainty of the estimated model parameters, which is represented by a Gaussian prior. The objective function in a Bayesian classification network is formed as the regularized cross-entropy error function. The regularized model is constructed not only by calculating the regularized parameters according to the maximum a posteriori criterion but also by estimating the Gaussian hyperparameter by maximizing the marginal likelihood. A rapid approximation to a Hessian matrix is developed to implement the Bayesian RNN-LM (BRNN-LM) by selecting a small set of salient outer-products. The proposed BRNN-LM achieves a sparser model than the RNN-LM. Experiments on different corpora show the robustness of system performance by applying the rapid BRNN-LM under different conditions. [ABSTRACT FROM AUTHOR]

In decentralized control systems with linear dynamics, quadratic cost, and Gaussian disturbances (also called decentralized LQG systems) linear control strategies are not always optimal. Nonetheless, linear control strategies are appealing due to their analytic and implementation simplicity. In this paper, we investigate decentralized LQG systems with partial history sharing information structure and identify finite-dimensional sufficient statistics for such systems. Unlike prior work on decentralized LQG systems, we do not assume partial nestedness or quadratic invariance. Our approach is based on the common information approach of Nayyar et al., 2013 and exploits the linearity of the system dynamics and control strategies. To illustrate our methodology, we identify sufficient statistics for linear strategies in decentralized systems where controllers communicate over a strongly connected graph with finite delays, and for decentralized systems consisting of coupled subsystems with control sharing or one-sided one step delay sharing information structures. [ABSTRACT FROM PUBLISHER]

This paper shows a series of self-critical reflections of the reality of Latin American volcanology, from an analysis of its strengths, weaknesses, opportunities, and threats (SWOT) held in February 2008 in Antigua, Guatemala. Before the analysis, an account of the efforts made to unite the Latin American volcanological community is presented, up to the formation of an association (the Latin American Association of Volcanology, ALVO according to its Spanish acronym) that will strengthen and promote partnerships between Latin American volcanologists and their institutions for the benefit of society, particularly during eruptive crisis of the numerous active volcanoes in the Latin American region. [ABSTRACT FROM AUTHOR]

This paper examines the history, forms and nature of oral and musical discourses contained in interactive radio programmes and, in parallel, internet chat forums that have come to the fore with the breaking up of the Malawi Broadcasting Corporation's (MBC) monopoly after the onset of 'multi-party' rule in 1994. It attempts to demonstrate how they have been exploited, first, by broadcasters both to entertain and foster a feeling of 'freedom of speech' and, secondly, by various institutional, social and political actors to foster this feeling of freedom of speech as well as for their own class needs. Although appearing to give equity of voice to all, the modes of entry into 'direct' talk radio are determined by infrastructural factors like the internet, internet cafes, fixed and mobile phones and possession of 'phone units'; as well as peoples' political, cultural or religious views. Before a piece of music can be broadcast it has to be 'composed, recorded, promoted and requested', an 'indirect' process that brings in a conflicting mix of promoters, patrons, musicians and, often, disc jockeys' preferences and politics. Similarly access to internet chat forums and newspapers requires access to internet technology (IT). After examination using a number of case studies, the commonalities in interactive talk, music radio programmes and internet media in relation to powerful and not so powerful forces whether personal, institutional or national, against the disparities and specifics of class, culture and urbanity, it is concluded that, in the case of Malawi, the proliferation of media has separated the social classes even further, with different sections 'chattering unto themselves'. This, it is suggested, is an impediment to a participatory developmental democracy. [ABSTRACT FROM AUTHOR]

The article presents the author's comments as a citizen scientist working on the Old Weather Navy web-based project for deciphering climate data recorded in antique ship logbooks. Topics include the use of historical data in climate modeling, the transcription of weather data recorded in ship logs, and the volunteer model for transcription and climatology data collection by the Old Weather Navy.

This paper traces representations and contestations of colonial and postcolonial Malawian identities through artistic and cultural discourses. I argue that the relevant identities were produced in several phases: first by pre-colonial dynamics; second by the colonising process producing an economic migrant population; third, by the post-independence Cabinet Crisis of 1964 and Dr Banda's dictatorship producing marginalised exiled dissidents and, by association, a marginalised Malawi Diaspora; and finally the po st-1994 largely economic migration facilitated by globalisation and the freedom of movement. I will contend that a significant section of domiciled² elite, as opposed to rural Malawians, consider that 'M alawians', in the sense of citizenship rights, are only those domiciled in Malawi. Most Diaspora Malawians, however, consider themselves Malawian but face marginalisation through distance, denial of Malawi political and cultural rights as well as the questioning of their Malawian identity. This denial of rights, with aspects traceable to the colonial period, became sequentially more focused with the end of the Federation, attainment of independence, and as Dr Banda used it as a way of excluding troublesome political elements. This pattern of marginalising Diaspora Malawians has persisted despite economic ties and the 'unity of purpose' between domiciled and Diaspora opposition elements during the 1991 - 1994 transition to multiparty rule. Political, poetic, linguistic, musical, artistic and other cultural discourses are used to define and perpetuate the marginalisation. Though former long-term exiles. Dr Banda and Dr Mutharika recruited cultural discourses to marginalise external opponents. Paradoxically, any Diaspora Malawians who distinguish themselves in the arts, business, sport or other activities abroad is accorded 'Malawian-ness'. The most significant relationship between domiciled and Diaspora Malawians remains economic and intellectual. Malawians in the Diaspora remit significant amounts of financial and intellectual resources and those domiciled in Malawi control all access to citizenship rights. [ABSTRACT FROM AUTHOR]

The article looks at the use of Montreal, Quebec as a base for clandestine Confederate meetings during the U.S. Civil War. It looks at how Confederate President Jefferson Davis sent former Cabinet member Jacob Thompson to Montreal to organize a secret service that would raid the northern U.S. Thompson's plots included destabilizing the Union economy by converting paper money into gold, bioterrorism with yellow fever, and kidnapping President Abraham Lincoln.

We consider online learning in finite stochastic Markovian environments where in each time step a new reward function is chosen by an oblivious adversary. The goal of the learning agent is to compete with the best stationary policy in hindsight in terms of the total reward received. Specifically, in each time step the agent observes the current state and the reward associated with the last transition, however, the agent does not observe the rewards associated with other state-action pairs. The agent is assumed to know the transition probabilities. The state of the art result for this setting is an algorithm with an expected regret of O(T^2/3\ln T). In this paper, assuming that stationary policies mix uniformly fast, we show that after T time steps, the expected regret of this algorithm (more precisely, a slightly modified version thereof) is O(T^1/2\ln T), giving the first rigorously proven, essentially tight regret bound for the problem. [ABSTRACT FROM AUTHOR]

A reprint of the article "A History of the Past: Life Reeked With Joy," compiled by Anders Henriksson, which appeared in the Spring 1983 issue of "Wilson Quarterly," is presented. It is comprised of humorous excerpts from student papers on world history, in which malapropisms and factual errors feature heavily. Topics include the Middle Ages, the Reformation, World War I, and Nazi leader Adolph Hitler.

Subsystems that are coupled due to dynamics and costs arise naturally in various communication applications. In many such applications the control actions are shared between different control stations giving rise to a control sharing information structure. Previous studies of control-sharing have concentrated on the linear quadratic Gaussian setup and a solution approach tailored to continuous valued control actions. In this paper a three step solution approach for finite valued control actions is presented. In the first step, a person-by-person approach is used to identify redundant data or a sufficient statistic for local information at each control station. In the second step, the common-information based approach of Nayyar (2013) is used to find a sufficient statistic for the common information shared between all control stations and to obtain a dynamic programming decomposition. In the third step, the specifics of the model are used to simplify the sufficient statistic and the dynamic program. [ABSTRACT FROM AUTHOR]

The article focuses on the constitutionality of the U.S. National Security Agency's (NSA) spying on all Americans. It states the Fourth Amendment of the Constitution provides people the right to be secure in their persons, papers, houses, and effects against unreasonable search and seizure and mentions in colonial America officials of the British Crown conducted mass searches of houses and persons despite the English Court's Saman's Case of 1603. It comments on Judge William H. Pauley III's ruling Americans cannot file suit against the NSA when he dismissed a lawsuit by the American Civil Liberties Union due to legislation in the Patriot Act requiring the spying be kept secret forever. It mentions a report by the independent Privacy and Civil Liberties Oversight Board on telephone spying.

The North Caucasus has long been one of the most turbulent regions in Eurasia. Events such as the secessionist conflicts in Chechnya in the 1990s, the growing radicalization and the spread of insurgency groups across the region, and most recently discussions over the prospects for, and the security of, the hosting of the 2014 Winter Olympics alongside rising local Circassian nationalism on the ground in Sochi have grabbed the headlines both in Russia and internationally. These events are set against a background of a general rise in nationalism and ongoing anti-Caucasian sentiment in Russia. This paper investigates the roots causes of these complex developments, and the impact that this region is likely to have on Russian and regional politics in the next decade. [ABSTRACT FROM AUTHOR]

This paper considers a class of scenarios where targets emerge from some known location and move towards some unknown destinations in a weighted acyclic digraph. A decision maker with knowledge of the target positions must decide when preparations should be made at any given destination for their arrival. The decision maker faces a timing tradeoff: early decisions mean more time for preparation at the cost of higher uncertainty in the target's true destination while later decisions mean less uncertainty at the cost of having less time to prepare. We show how this problem can be formulated as an optimal stopping problem on a Markov chain. This sets the basis for the introduction of the best investment algorithm which prescribes when investments must be made conditioned on the target's motion along the digraph. We establish the optimality of this prescription and examine its robustness against changes in the problem parameters, identifying sufficient conditions to determine whether the solution computed by the best investment algorithm remains optimal. Based on this analysis, we develop the self-triggered acquisition&decision algorithm that allows the decision maker, under partial knowledge of the parameter dynamics, to schedule in advance when to check if the control policy in its memory remains optimal and, if this test fails, when to recompute it. Finally, we obtain worst case lower bounds on the maximum time that can elapse under arbitrary parameter dynamics before the optimal solution must be recomputed. Simulations illustrate our results. [ABSTRACT FROM AUTHOR]

The article discusses the 2012 National History Day (NHD) Contest. The contest involved the participation of more than 600,000 middle and high school students in the U.S. and abroad who created projects and wrote papers based on the theme "Revolution, Reaction, Reform in History." The author describes attending the closing ceremony of the contest where the winners were announced. Comments by Cathy Gorn, NHD's executive director, are presented.

In this paper, we consider the safety control problem for hidden mode hybrid systems (HMHSs), which are a special class of hybrid automata in which the mode is not available for control. For these systems, safety control is a problem with imperfect state information. We tackle this problem by introducing the notion of nondeterministic discrete information state and by translating the problem to one with perfect state information. The perfect state information control problem is obtained by constructing a new hybrid automaton, whose discrete state is an estimate of the HMHS mode and is, as such, available for control. This problem is solved by computing the capture set and the least restrictive control map for the new hybrid automaton. Sufficient conditions for the termination of the algorithm that computes the capture set are provided. Finally, we show that the solved perfect state information control problem is equivalent to the original problem with imperfect state information under suitable assumptions. We illustrate the application of the proposed technique to a collision avoidance problem between an autonomous vehicle and a human driven vehicle at a traffic intersection. [ABSTRACT FROM PUBLISHER]

In this paper, we propose a new tractable framework for dealing with linear dynamical systems affected by uncertainty, applicable to multistage robust optimization and stochastic programming. We introduce a hierarchy of near-optimal polynomial disturbance-feedback control policies, and show how these can be computed by solving a single semidefinite programming problem. The approach yields a hierarchy parameterized by a single variable (the degree of the polynomial policies), which controls the trade-off between the optimality gap and the computational requirements. We evaluate our framework in the context of three classical applications—two in inventory management, and one in robust regulation of an active suspension system—in which very strong numerical performance is exhibited, at relatively modest computational expense. [ABSTRACT FROM AUTHOR]

Information delays exist when the most recent inventory information available to the Inventory Manager (IM) is dated. In other words, the IM observes only the inventory level that belongs to an earlier period. Such situations are not uncommon, and they arise when it takes a while to process the demand data and pass the results to the IM. In this paper, we establish that the average cost optimal policy is of state-dependent basestock type with respect to the reference inventory position. We show that the optimal base stock depends on the age and the magnitude of the latest observed delay. We illustrate the results by solving an example with delays of 0 and 1, for which we are able to obtain formulas/bounds for the basestock levels. [ABSTRACT FROM AUTHOR]