638,366 research outputs found

    Do we measure what we get?

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    Performance measures shall enhance the performance of companies by directing the attention of decision makers towards the achievement of organizational goals. Therefore, goal congruence is regarded in literature as a major factor in the quality of such measures. As reality is affected by many variables, in practice one has tried to achieve a high degree of goal congruence by incorporating an increasing number of these variables into performance measures. However, a goal congruent measure does not lead automatically to superior decisions, because decision makers’ restricted cognitive abilities can counteract the intended effects. This paper addresses the interplay between goal congruence and complexity of performance measures considering cognitively-restricted decision makers. Two types of decision quality are derived which allow a differentiated view on the influence of this interplay on decision quality and learning. The simulation experiments based on this differentiation provide results which allow a critical reflection on costs and benefits of goal congruence and the assumptions regarding the goal congruence of incentive systems

    Statistical framework for video decoding complexity modeling and prediction

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    Video decoding complexity modeling and prediction is an increasingly important issue for efficient resource utilization in a variety of applications, including task scheduling, receiver-driven complexity shaping, and adaptive dynamic voltage scaling. In this paper we present a novel view of this problem based on a statistical framework perspective. We explore the statistical structure (clustering) of the execution time required by each video decoder module (entropy decoding, motion compensation, etc.) in conjunction with complexity features that are easily extractable at encoding time (representing the properties of each module's input source data). For this purpose, we employ Gaussian mixture models (GMMs) and an expectation-maximization algorithm to estimate the joint execution-time - feature probability density function (PDF). A training set of typical video sequences is used for this purpose in an offline estimation process. The obtained GMM representation is used in conjunction with the complexity features of new video sequences to predict the execution time required for the decoding of these sequences. Several prediction approaches are discussed and compared. The potential mismatch between the training set and new video content is addressed by adaptive online joint-PDF re-estimation. An experimental comparison is performed to evaluate the different approaches and compare the proposed prediction scheme with related resource prediction schemes from the literature. The usefulness of the proposed complexity-prediction approaches is demonstrated in an application of rate-distortion-complexity optimized decoding

    Proceedings of the ECCS 2005 satellite workshop: embracing complexity in design - Paris 17 November 2005

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    Embracing complexity in design is one of the critical issues and challenges of the 21st century. As the realization grows that design activities and artefacts display properties associated with complex adaptive systems, so grows the need to use complexity concepts and methods to understand these properties and inform the design of better artifacts. It is a great challenge because complexity science represents an epistemological and methodological swift that promises a holistic approach in the understanding and operational support of design. But design is also a major contributor in complexity research. Design science is concerned with problems that are fundamental in the sciences in general and complexity sciences in particular. For instance, design has been perceived and studied as a ubiquitous activity inherent in every human activity, as the art of generating hypotheses, as a type of experiment, or as a creative co-evolutionary process. Design science and its established approaches and practices can be a great source for advancement and innovation in complexity science. These proceedings are the result of a workshop organized as part of the activities of a UK government AHRB/EPSRC funded research cluster called Embracing Complexity in Design (www.complexityanddesign.net) and the European Conference in Complex Systems (complexsystems.lri.fr). Embracing complexity in design is one of the critical issues and challenges of the 21st century. As the realization grows that design activities and artefacts display properties associated with complex adaptive systems, so grows the need to use complexity concepts and methods to understand these properties and inform the design of better artifacts. It is a great challenge because complexity science represents an epistemological and methodological swift that promises a holistic approach in the understanding and operational support of design. But design is also a major contributor in complexity research. Design science is concerned with problems that are fundamental in the sciences in general and complexity sciences in particular. For instance, design has been perceived and studied as a ubiquitous activity inherent in every human activity, as the art of generating hypotheses, as a type of experiment, or as a creative co-evolutionary process. Design science and its established approaches and practices can be a great source for advancement and innovation in complexity science. These proceedings are the result of a workshop organized as part of the activities of a UK government AHRB/EPSRC funded research cluster called Embracing Complexity in Design (www.complexityanddesign.net) and the European Conference in Complex Systems (complexsystems.lri.fr)

    LightChain: A DHT-based Blockchain for Resource Constrained Environments

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    As an append-only distributed database, blockchain is utilized in a vast variety of applications including the cryptocurrency and Internet-of-Things (IoT). The existing blockchain solutions have downsides in communication and storage efficiency, convergence to centralization, and consistency problems. In this paper, we propose LightChain, which is the first blockchain architecture that operates over a Distributed Hash Table (DHT) of participating peers. LightChain is a permissionless blockchain that provides addressable blocks and transactions within the network, which makes them efficiently accessible by all the peers. Each block and transaction is replicated within the DHT of peers and is retrieved in an on-demand manner. Hence, peers in LightChain are not required to retrieve or keep the entire blockchain. LightChain is fair as all of the participating peers have a uniform chance of being involved in the consensus regardless of their influence such as hashing power or stake. LightChain provides a deterministic fork-resolving strategy as well as a blacklisting mechanism, and it is secure against colluding adversarial peers attacking the availability and integrity of the system. We provide mathematical analysis and experimental results on scenarios involving 10K nodes to demonstrate the security and fairness of LightChain. As we experimentally show in this paper, compared to the mainstream blockchains like Bitcoin and Ethereum, LightChain requires around 66 times less per node storage, and is around 380 times faster on bootstrapping a new node to the system, while each LightChain node is rewarded equally likely for participating in the protocol

    The Qualitative Analysis of Factors Influencing the Adoption Rate of Reward-Based Crowdfunding by Polish Filmmakers

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    The aim of this article is to analyze and discuss the factors impacting the process of the implementation of crowdfunding by the Polish film industry. The presented study is based on the qualitative approach: unstructured or semistructured interviews, questionnaires and the analysis of case studies. The respondents enumerated and evaluated a wide spectrum of factors facilitating and hindering the adoption rate: from general barriers (e.g. legal regulation of crowdfunding) to very specific aspects for filmmaking (e.g. the unprofessional promotional video of the crowdfunding project). The findings highlighted the significance of the following factors: the existing strong filmmakers’ attitude that ‘crowdfunding is for film beginners’, the complexity of team management (film crew) during the process of crowdfunding campaigns, and the cultural aspects of seeking financial support from friends.Celem artykuƂu jest analiza i omĂłwienie czynnikĂłw wpƂywających na proces implementacji crowdfundingu przez polski sektor filmowy. Zaprezentowane w artykule badania zostaƂy oparte na metodach jakoƛciowych: nieustrukturalizowanych lub częƛciowo ustrukturalizowanych wywiadach i kwestionariuszach oraz na analizie studium przypadkĂłw. Respondenci wskazali i dokonali ewaluacji szerokiego spektrum czynnikĂłw wspierających i hamujących proces akceptacji innowacji, jaką jest crowdfunding: od ogĂłlnych barier (np. legislacji prawnych dotyczących crowdfundingu), po czynniki ƛciƛle związane z produkcją filmową (np. nieprofesjonalne wideo promujące projekt crowdfundingowy). Wyniki badaƄ podkreƛlają szczegĂłlne znaczenie następujących czynnikĂłw: silnej postawy respondentĂłw oceniającej crowdfunding jako narzędzie dla początkujących filmowcĂłw, zƂoĆŒonoƛć procesu zarządzania zespoƂem (ekipą filmową) w trakcie realizacji projektu kampanii crowdfundingowej oraz aspekt kulturowy dotyczący szukania wsparcia dla projektu wƛrĂłd grona znajomych

    Solving Hard Control Problems in Voting Systems via Integer Programming

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    Voting problems are central in the area of social choice. In this article, we investigate various voting systems and types of control of elections. We present integer linear programming (ILP) formulations for a wide range of NP-hard control problems. Our ILP formulations are flexible in the sense that they can work with an arbitrary number of candidates and voters. Using the off-the-shelf solver Cplex, we show that our approaches can manipulate elections with a large number of voters and candidates efficiently
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