Self-Optimizing and Pareto-Optimal Policies in General Environments based on Bayes-Mixtures

The problem of making sequential decisions in unknown probabilistic environments is studied. In cycle $t$ action $y_t$ results in perception $x_t$ and reward $r_t$, where all quantities in general may depend on the complete history. The perception $x_t$ and reward $r_t$ are sampled from the (reactive) environmental probability distribution $\mu$. This very general setting includes, but is not limited to, (partial observable, k-th order) Markov decision processes. Sequential decision theory tells us how to act in order to maximize the total expected reward, called value, if $\mu$ is known. Reinforcement learning is usually used if $\mu$ is unknown. In the Bayesian approach one defines a mixture distribution $\xi$ as a weighted sum of distributions \nu\in\M, where \M is any class of distributions including the true environment $\mu$. We show that the Bayes-optimal policy $p^\xi$ based on the mixture $\xi$ is self-optimizing in the sense that the average value converges asymptotically for all \mu\in\M to the optimal value achieved by the (infeasible) Bayes-optimal policy $p^\mu$ which knows $\mu$ in advance. We show that the necessary condition that \M admits self-optimizing policies at all, is also sufficient. No other structural assumptions are made on \M. As an example application, we discuss ergodic Markov decision processes, which allow for self-optimizing policies. Furthermore, we show that $p^\xi$ is Pareto-optimal in the sense that there is no other policy yielding higher or equal value in {\em all} environments \nu\in\M and a strictly higher value in at least one.Comment: 15 page

The debate on warlordism: the importance of military legitimacy

Despite the careless use of the terms ' warlord' and ' warlordism' by the media, both have become increasingly popular among academics, even if some scholars object to their use. This paper draws on direct field experience as well as the ongoing debate. It aims, on the one hand, to reconcile the different perspectives - which are often not necessarily at odds with each other - and on the other hand, to propose a definition of 'warlordism' for the social sciences that is both closer to that used so far by historians and at the same time consistent with emerging evidence from the field

The Efficacy of Police Interventions towards Resolution of Conflicts within the Illemi Triangle

Intervention of security agencies is considered key to lasting peace. This is especially crucial to attaining peace in communities where socio-cultural beliefs advocate for revege. The study sought to examine the efficacy of police interventions towards resolution of conflicts within the Illemi Triangle. The study adopted neo-realism and conflict theories, while employing exploratory research design. The target population included all the households in Kibish sub-county (Kenyan), Narus and Mogos in South Sudan. A stratified random sample of 432 household heads and 30 key informants was selected from the three administrative units. Data collection tools used included household survey interviews, Focus Group Discussions (FGDs) and in depth interviews. The collected data was analyzed qualitatively and quantitatively. The study established that the communities within the Illemi Triangle rarely sought police interventions during their conflicts. They instead armed themselves with varied weapons to fight each other. The study concludes that failure to entrust security agencies with ensuring peace within the Illemi Triangle has played a great part to exacerbate the current conflicts in the Triangle. The findings of this study are of great significance to the governments of the two states in addressing the complexities occasioned by the disputed territorial boundaries affecting conflict management among the communities along the borders of the two states. (211 Words) Key words: Illemi Triangle, cross border conflict, police interventions, lasting peace

Bases of prestige among high and low delinquent street-corner groups

Thesis (Ph.D.)--Boston UniversityIn order to determine differential bases of prestige, this study compared two age segments of a highly delinquent street-corner group with the two corresponding age segments of a moderately delinquent street-corner group. The corresponding age segments were matched for age, ethnicity, and religion. There were 116 boys in all. The data were obtained from the process records of "detached social workers" who observed the groups for periods averaging 18 months. These field data were subjected to a standardized content analysis system formulated within the cultural anthropological framework. A 19 percent random sample of prestige-oriented acts from this universe constituted the study population. IBM procedure was utilized to obtain tabulations of interaction with reference to cultural practices (drinking, fighting), sports, and club activities, and worker functions. Cultural practices and sportsclub activities were classified into those reflecting lower class, middle class, and adolescent behavior. This was supplemented by scanning the qualitative data. The findings showed that high delinquency was associated with lower social class, lack of father figures, high commitment to lower class behavior, and low in-volvement in age-linked adolescent activities. There was a noticeable lack of concern with middle class behavior. Conversely, moderate delinquenqy was related to somewhat higher social class, presence of father figures, less involvement in lower class behavior, and high commitment to adolescent supported behavior. This group also showed a negligible involvement in middle class behavior. It was apparent from the data that differential group functions reflected differential social organization and acculturation. The functions performed by the groups were related to aspects of lower class subculture. The greater involvement in lower class culture by the more delinquent groups, indicated that the etiology of delinquency can be better understood by further investigating that subculture. [TRUNCATED

Nation state meets popular culture : the construction of Chinese nationalism in anti-Japanese war dramas

textThis thesis explores how Anti-Japanese War Drama in Chinese TV becomes a field of negotiation in which the forces of dominant state ideology, liberal market and alternative discourses meet. Focusing how the notion of Chinese nationalism has been constructed in the negotiation, this work examines TV dramas as a homogenizing national project in which market forces and state intervention are no longer at odd with each other. By critically reading representations and narratives of bandits and women in two dramas To Advance towards the Fire and Auntie Duohe, the study points out how dominant nationalist discourses attempt to incorporate the marginalized or disadvantaged group as a consistent part of the nation. However, the anti-Japanese war dramas still allow a space for the alternative discourse to emerge which disturbs the perceived coherence of the nation.Radio-Television-Fil

Lexical co-occurrence and lexical inheritance. emotion lexemes in German: a lexicographic case study

In the present paper, we tackle the problem of the compact and efficient representation of restricted lexical co-occurrence information in the lexicon along semantic lines. The theoretical framework for this study is the Meaning Text Theory (MTT) and, more specifically, the lexicographic part of MIT --- the Explanatory Combinatorial Dictionary (ECD), which contains for each lexeme (i) its semantic definition, (ii) a systematic description of its restricted lexical co-occurrence in terms of Lexical Functions(LF), and (iii) its Government Pattern. The data domain is the semantic field of emotion lexemes in German. In order to represent the restricted lexical co-occurrence (or collocations) of the lexemes in this field, we suggest the following procedure:1.    Construct approximate descriptions of their meaning, i.e. what we call the abridged lexicographic definitions. Formulated in terms of semantic features, these definitions are supposed to provide as much semantic information as necessary for establishing correlations between the semantic features of a lexeme and its collocates.2.    Specify their syntactic Government Patterns, which are needed for a clearer picture of their co-occurrence --- syntactic as well as lexical.3.    Specify their restricted lexical co-occurrence with the verbs chosen.4.    Establish correlations between the values of LFs and the semantic features in the abridged definitions of the emotion lexemes.5.    Based on these correlations, extract recurrent values of LFs (and recurrent Government Patterns) from individual lexical entries and list them under what we call the generic lexeme of the semantic field under study --- in this case, GEFÜHL 'emotion'. This leads on the one hand, to "compressed" lexical entries for emotion lexemes, and on the other hand, to the creation of a lexical entry of a new type: the "public" entry of a generic lexeme.Keywords: lexicography, lexicon, german emotion lexemes, lexical co-occurrence, collocations, meaning text theory, lexical functions, semantic features, semantico-lexical correlations, information extraction, inheritance, individual lexical subentry, public lexical subentr

The Diamond, February 22, 2017

Front Page: Dordt Music Director Leaves His Mark; A New Whey to Deal with Byproducts News: Dordt Campus No Stranger to Eating Disorders; Cultural Fair Draws Local Community; Engineers Debut Pulse Jet; Solar Panels Reach Liberia; HireDefenders: A New Way to Job Search?; Flooding in West Hall Opinion: How Rejecting the Notion of White Privilege Begets Racism; Coffee Corner: The Old Factory; The Dutch Donald Trump Editorial: Letter to the Editor; Busting the Myth of Group Work; Not My Home Country Sports: Indoor Track and Field Excels with Home-Court Advantage ; Walk in the Shoes of a Football Team Intern; Paige Engbers; Men\u27s Basketball Wraps Up Arts & Entertainment: Prairie Grass Films Awarded; John Wick: Ch. 2: Kill Everything; Sky Full of Stars; RUSH 2017 Debuts Thursday The Back Page: CZ\u27s Bleacher Meditations: Does Baylor Football Deserve the Death Penalty?; A Fountain in the Rainhttps://digitalcollections.dordt.edu/dordt_diamond/1782/thumbnail.jp

Community perceptions and adaptation to climate change in coastal Bangladesh

This research examines local understandings and perceptions of climate change in two coastal villages in Southwest Bangladesh. Based on a combination of survey data and ethnographic field research, it shows how the livelihoods of the inhabitants of the two villages have been affected by various development interventions in the past, more recent changes in local weather patterns and their adaptation to these changes.These adaptive responses are shown to fall within a resilience framework