195 research outputs found

    Designing smart markets

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    Electronic markets have been a core topic of information systems (IS) research for last three decades. We focus on a more recent phenomenon: smart markets. This phenomenon is starting to draw considerable interdisciplinary attention from the researchers in computer science, operations research, and economics communities. The objective of this commentary is to identify and outline fruitful research areas where IS researchers can provide valuable contributions. The idea of smart markets revolves around using theoretically supported computational tools to both understand the characteristics of complex trading environments and multiechelon markets and help human decision makers make real-time decisions in these complex environments. We outline the research opportunities for complex trading environments primarily from the perspective o

    Multi-Band Intra-Night Optical Variability of BL Lacertae

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    We monitored BL Lacertae frequently during 2014 - 2016 when it was generally in a high state. We searched for intra-day variability for 43 nights using quasi-simultaneous measurements in the B, V, R, and I bands (totaling 143 light curves); the typical sampling interval was about eight minutes. On hour-like timescales, BL Lac exhibited significant variations during 13 nights in various optical bands. Significant spectral variations are seen during most of these nights such that the optical spectrum becomes bluer when brighter. The amplitude of variability is usually greater for longer observations but is lower when BL Lac is brighter. No evidence for periodicities or characteristic variability time-scales in the light curves was found. The color variations are mildly chromatic on long timescales.Comment: 15 pages, 5 Figures, 3 Tables; Accepted for publication in Galaxies; a special issue on Microvariability of Blazar

    Information Transparency in B2B Auction Markets: The Role of Winner Identity Disclosure

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    We study the impact of information transparency in B2B auctions. Specifically, we measure the effect of concealing winners’ identities on auction outcomes using a large-scale, quasi-natural field experiment. Contrary to the conventional wisdom that “the more information, the better,” we find that concealing winners’ identities leads to a significant increase in price by approximately 6%, and such effect holds true across both online and offline channels as well as different types of bidders. We further explore the mechanism that drives the observed effect. The empirical analysis suggests that the price increase may primarily stem from the disruption of imitative bidding which relies on the identification of fellow competitors. Our findings have important implications for the design of auction markets, especially multi-channel B2B markets

    Frequency dependent core shifts and parameter estimation for the blazar 3C 454.3

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    We study the core shift effect in the parsec scale jet of the blazar 3C 454.3 using the 4.8 GHz - 36.8 GHz radio light curves obtained from three decades of continuous monitoring. From a piecewise Gaussian fit to each flare, time lags Δt\Delta t between the observation frequencies Îœ\nu and spectral indices α\alpha based on peak amplitudes AA are determined. From the fit Δt∝Μ1/kr\Delta t \propto \nu^{1/k_r}, kr=1.10±0.18k_r = 1.10 \pm 0.18 indicating equipartition between the magnetic field energy density and the particle energy density. From the fit A∝ΜαA \propto \nu^\alpha, α\alpha is in the range −0.24-0.24 to 1.521.52. A mean magnetic field strength at 1 pc, B1=0.5±0.2B_1 = 0.5 \pm 0.2 G, and at the core, Bcore=46±16B_{\rm core} = 46 \pm 16 mG, are inferred, consistent with previous estimates. The measure of core position offset is ΩrÎœ=6.4±2.8\Omega_{r\nu} = 6.4 \pm 2.8 pc GHz1/kr^{1/k_r} when averaged over all frequency pairs. Based on the statistical trend shown by the measured core radius rcorer_{\rm core} as a function of Îœ\nu, we infer that the synchrotron opacity model may not be valid for all cases. A Fourier periodogram analysis yields power law slopes in the range −1.6-1.6 to −3.5-3.5 describing the power spectral density shape and gives bend timescales in the range 0.52−0.66 0.52 - 0.66~yr. This result, and both positive and negative α\alpha, indicate that the flares originate from multiple shocks in a small region. Important objectives met in our study include: the demonstration of the computational efficiency and statistical basis of the piecewise Gaussian fit; consistency with previously reported results; evidence for the core shift dependence on observation frequency and its utility in jet diagnostics in the region close to the resolving limit of very long baseline interferometry observations.Comment: 12 pages, 11 figures (23 sub-figures), 5 tables. Accepted for publication in MNRA

    Real-time Tactical and Strategic Sales Management for Intelligent Agents Guided By Economic Regimes

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    Many enterprises that participate in dynamic markets need to make product pricing and inventory resource utilization decisions in real-time. We describe a family of statistical models that address these needs by combining characterization of the economic environment with the ability to predict future economic conditions to make tactical (short-term) decisions, such as product pricing, and strategic (long-term) decisions, such as level of finished goods inventories. Our models characterize economic conditions, called economic regimes, in the form of recurrent statistical patterns that have clear qualitative interpretations. We show how these models can be used to predict prices, price trends, and the probability of receiving a customer order at a given price. These “regime” models are developed using statistical analysis of historical data, and are used in real-time to characterize observed market conditions and predict the evolution of market conditions over multiple time scales. We evaluate our models using a testbed derived from the Trading Agent Competition for Supply Chain Management (TAC SCM), a supply chain environment characterized by competitive procurement and sales markets, and dynamic pricing. We show how regime models can be used to inform both short-term pricing decisions and longterm resource allocation decisions. Results show that our method outperforms more traditional shortand long-term predictive modeling approaches

    Variability of the Spectral Energy Distribution of the Blazar S5 0716+714

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    The emission from blazars is known to be variable at all wavelengths. The flux variability is often accompanied by spectral changes. Spectral energy distribution (SED) changes must be associated with changes in the spectra of emitting electrons and/or the physical parameters of the jet. Meaningful modeling of blazar broadband spectra is required to understand the extreme conditions within the emission region. Not only is the broadband SED crucial, but also information about its variability is needed to understand how the highest states of emission occur and how they differ from the low states. This may help in discriminating between models. Here we present the results of our SED modeling of the blazar S5 0716+714 during various phases of its activity. The SEDs are classified into different bins depending on the optical brightness state of the source.Comment: 4 pages, 3 figures, contributed talk presented at the conference Multifrequency Variability of Blazars, Guangzhou, China, September 22-24, 2010. To appear in Journal of Astrophysics and Astronomy (JAA
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