1,221 research outputs found

    Rationality-Robust Information Design: Bayesian Persuasion under Quantal Response

    Full text link
    Classic mechanism/information design imposes the assumption that agents are fully rational, meaning each of them always selects the action that maximizes her expected utility. Yet many empirical evidence suggests that human decisions may deviate from this full rationality assumption. In this work, we attempt to relax the full rationality assumption with bounded rationality. Specifically, we formulate the bounded rationality of an agent by adopting the quantal response model (McKelvey and Palfrey, 1995). We develop a theory of rationality-robust information design in the canonical setting of Bayesian persuasion (Kamenica and Gentzkow, 2011) with binary receiver action. We first identify conditions under which the optimal signaling scheme structure for a fully rational receiver remains optimal or approximately optimal for a boundedly rational receiver. In practice, it might be costly for the designer to estimate the degree of the receiver's bounded rationality level. Motivated by this practical consideration, we then study the existence and construction of robust signaling schemes when there is uncertainty about the receiver's bounded rationality level

    Competitive Information Disclosure with Multiple Receivers

    Full text link
    This paper analyzes a model of competition in Bayesian persuasion in which two symmetric senders vie for the patronage of multiple receivers by disclosing information about the qualities (i.e., binary state -- high or low) of their respective proposals. Each sender is allowed to commit to a signaling policy where he sends a private (possibly correlated) signal to every receiver. The sender's utility is a monotone set function of receivers who make a patron to this sender. We characterize the equilibrium structure and show that the equilibrium is not unique (even for simple utility functions). We then focus on the price of stability (PoS) in the game of two senders -- the ratio between the best of senders' welfare (i.e., the sum of two senders' utilities) in one of its equilibria and that of an optimal outcome. When senders' utility function is anonymous submodular or anonymous supermodular, we analyze the relation between PoS with the ex ante qualities λ\lambda (i.e., the probability of high quality) and submodularity or supermodularity of utility functions. In particular, in both families of utility function, we show that PoS=1\text{PoS} = 1 when the ex ante quality λ\lambda is weakly smaller than 1/21/2, that is, there exists equilibrium that can achieve welfare in the optimal outcome. On the other side, we also prove that PoS>1\text{PoS} > 1 when the ex ante quality λ\lambda is larger than 1/21/2, that is, there exists no equilibrium that can achieve the welfare in the optimal outcome. We also derive the upper bound of PoS\text{PoS} as a function of λ\lambda and the properties of the value function. Our analysis indicates that the upper bound becomes worse as the ex ante quality λ\lambda increases or the utility function becomes more supermodular (resp.\ submodular)

    An Investigation of the Differential Expression of Her2/neu Gene Expression in Normal Oral Mucosa, Epithelial Dysplasia, and Oral Squamous Cell Carcinoma in Taiwan

    Get PDF
    BackgroundHer2/neu was thought to be a proto-oncogene with sequence homology to epidermal growth factor receptor (EGFR). Its overexpression was seen in many cancers and referred to regimens of anticancer therapy. The aim of this study was to investigate whether the abnormal expression existed in oral carcinogenesis.MethodsImmunohistochemistry (IHC) was used to detect Her2/neu expression in normal oral mucosa (NOM) (n = 20), oral precancerous lesions of epithelial dysplasia (ED) (n = 20), and oral squamous cell carcinoma (OSCC) (n = 30). The association of clinicopathologic covariates of areca use, tumor size, neck lymph node metastasis, differentiation and stages of cancer with the expression of Her2/neu was examined. The significance of Neu immunoreactivity in different groups or with different covariates was investigated using Fisher's exact test.ResultsHer2/neu immunoreactivity was very low with Her2/neu(+) in 10% (2/20) of NOM cases and in 25% (5/20) of ED cases, respectively. The Her2/neu expression was high in OSCC cases, with 40% (12/30) of Her2/neu(+) and 10% (3/30) of Her2/neu(++). Significant difference was observed between NOM/ED and OSCC cases (p < 0.05). All clinicopathologic covariates showed no significant relation to the expression of Her2/neu in OSCC cases.ConclusionThese findings suggested a dynamic change in Her2/neu expression during the development of OSCC. The overexpression of Her2/neu can be used as a marker in distinguishing NOM/ED from OSCC

    Assembling a cellulase cocktail and a cellodextrin transporter into a yeast host for CBP ethanol production

    Get PDF
    Background: Many microorganisms possess enzymes that can efficiently degrade lignocellulosic materials, but donot have the capability to produce a large amount of ethanol. Thus, attempts have been made to transform suchenzymes into fermentative microbes to serve as hosts for ethanol production. However, an efficient host for aconsolidated bioprocess (CBP) remains to be found. For this purpose, a synthetic biology technique that cantransform multiple genes into a genome is instrumental. Moreover, a strategy to select cellulases that interactsynergistically is needed.Results: To engineer a yeast for CBP bio-ethanol production, a synthetic biology technique, called “promoter-basedgene assembly and simultaneous overexpression” (PGASO), that can simultaneously transform and express multiplegenes in a kefir yeast, Kluyveromyces marxianus KY3, was recently developed. To formulate an efficient cellulasecocktail, a filter-paper-activity assay for selecting heterologous cellulolytic enzymes was established in this study andused to select five cellulase genes, including two cellobiohydrolases, two endo-β-1,4-glucanases and onebeta-glucosidase genes from different fungi. In addition, a fungal cellodextrin transporter gene was chosen totransport cellodextrin into the cytoplasm. These six genes plus a selection marker gene were one-step assembledinto the KY3 genome using PGASO. Our experimental data showed that the recombinant strain KR7 could expressthe five heterologous cellulase genes and that KR7 could convert crystalline cellulose into ethanol.Conclusion: Seven heterologous genes, including five cellulases, a cellodextrin transporter and a selection marker,were simultaneously transformed into the KY3 genome to derive a new strain, KR7, which could directly convertcellulose to ethanol. The present study demonstrates the potential of our strategy of combining a cocktailformulation protocol and a synthetic biology technique to develop a designer yeast host

    Dish Discovery via Word Embeddings on Restaurant Reviews

    Get PDF
    ABSTRACT This paper proposes a novel framework for automatic dish discovery via word embeddings on restaurant reviews. We collect a dataset of user reviews from Yelp and parse the reviews to extract dish words. Then, we utilize the processed reviews as training texts to learn the embedding vectors of words via the skip-gram model. In the paper, a nearestneighbor like score function is proposed to rank the dishes based on their learned representations. We brief some analyses on the preliminary experiments and present a web-based visualization at http://clip.csie.org/yelp/. Keywords dish discovery, word embeddings, dish-word extraction BACKGROUND With the growth of social media, corporations, such as Yelp, have accumulated a great number of user generated content (UGC). In the literature, some studies have been conducted with a perspective of finding critical information hidden in the content METHODOLOGY Copyright held by the author(s). RecSys 2016 Poster Proceedings, September 15-19, 2016, USA, Boston. Our methodology mainly consists of three parts: 1) dishword recognition, 2) word embedding learning, and 3) dish score calculation. As alluded to earlier, UGC usually incorporates a degree of noise and different language usages; therefore, extracting dish names from user reviews is a complicated task. For example, observed from the dataset, users tend not to write the full name of a dish in their reviews; instead, the last word or the last two words are often written in the reviews. To grapple with this issue, we use regular expressions (regexps) to extract dish names from the user reviews. However, this also give rise to an issue that a certain dish in a restaurant may be of the same name in other restaurants, which may induce the problem of ambiguity and lower the accuracy of matching the correct dish name. So, we attach a dish name with its restaurant name to solve the ambiguity problem. We then utilize the collection of processed reviews as training texts to learn embeddings of each word in the reviews via a continuous space language model, the skip-gram model. After the training phase, each word (including every dish) is represented by an n-dimensional vector (called the embedding of this word). Inspired by the k-nearest neighbors algorithm, we define the score for every dish d as: where , m is the total number of positive sentiment words considered, λi (i = 1, · · · , m) is a weighting parameter. In addition, si denotes the i-nearest positive sentiment words of the given dish d, and w d , ws i ∈ R n are the vector representations of the dish d and the sentiment word si, respectively. In an extreme case (1) of λm = 1 and λi = 0 for i = 1, · · · , m − 1, this score function implements the concept of the average Euclidean distance between a dish and all the positive sentiment words; while in the case (2) λ1 = 1 and λi = 0 for i = 2, · · · , m, the scored is obtained with the closest positive sentiment words to the dish. EXPERIMENTS Our preliminary experiments involve a real-world restaurant review dataset collected from Yelp Data Challenge

    A Biomimetic Membrane Device That Modulates the Excessive Inflammatory Response to Sepsis

    Get PDF
    OBJECTIVE: Septic shock has a clinical mortality rate approaching fifty percent. The major clinical manifestations of sepsis are due to the dysregulation of the host's response to infection rather than the direct consequences of the invading pathogen. Central to this initial immunologic response is the activation of leukocytes and microvascular endothelium resulting in cardiovascular instability, lung injury and renal dysfunction. Due to the primary role of leukocyte activation in the sepsis syndrome, a synthetic biomimetic membrane, called a selective cytopheretic device (SCD), was developed to bind activated leukocytes. The incorporation of the SCD along an extracorporeal blood circuit coupled with regional anticoagulation with citrate to lower blood ionized calcium was devised to modulate leukocyte activation in sepsis. DESIGN: Laboratory investigation. SETTING: University of Michigan Medical School. SUBJECTS: Pigs weighing 30-35 kg. INTERVENTIONS: To assess the effect of the SCD in septic shock, pigs were administered 30×10(10) bacteria/kg body weight of Escherichia coli into the peritoneal cavity and within 1 hr were immediately placed in an extracorporeal circuit containing SCD. MEASUREMENTS AND MAIN RESULTS: In this animal model, the SCD with citrate compared to control groups without the SCD or with heparin anticoagulation ameliorated the cardiovascular instability and lung sequestration of activated leukocytes, reduced renal dysfunction and improved survival time compared to various control groups. This effect was associated with minimal elevations of systemic circulating neutrophil activation. CONCLUSIONS: These preclinical studies along with two favorable exploratory clinical trials form the basis of an FDA-approved investigational device exemption for a pivotal multicenter, randomized control trial currently underway

    SDSS J013127.34-032100.1: A newly discovered radio-loud quasar at z=5.18z=5.18 with extremely high luminosity

    Full text link
    Only very few z>5 quasars discovered to date are radio-loud, with a radio-to-optical flux ratio (radio-loudness parameter) higher than 10. Here we report the discovery of an optically luminous radio-loud quasar, SDSS J013127.34-032100.1 (J0131-0321 in short), at z=5.18+-0.01 using the Lijiang 2.4m and Magellan telescopes. J0131-0321 has a spectral energy distribution consistent with that of radio-loud quasars. With an i-band magnitude of 18.47 and radio flux density of 33 mJy, its radio-loudness parameter is ~100. The optical and near-infrared spectra taken by Magellan enable us to estimate its bolometric luminosity to be L_bol ~ 1.1E48 erg/s, approximately 4.5 times greater than that of the most distant quasar known to date. The black hole mass of J0131-0321 is estimated to be 2.7E9 solar masses, with an uncertainty up to 0.4 dex. Detailed physical properties of this high-redshift, radio-loud, potentially super-Eddington quasar can be probed in the future with more dedicated and intensive follow-up observations using multi-wavelength facilities.Comment: 5 pages, 3 figures, accepted to ApJ

    Genetic diversity and C2-like subgenogroup strains of enterovirus 71, Taiwan, 2008

    Get PDF
    <p>Abstract</p> <p>Background</p> <p>Human enterovirus 71 (EV-71) is known of having caused numerous outbreaks of hand-foot-mouth disease, and other clinical manifestations globally. In 2008, 989 EV-71 strains were isolated in Taiwan.</p> <p>Results</p> <p>In this study, the genetic and antigenic properties of these strains were analyzed and the genetic diversity of EV-71 subgenogroups surfacing in Taiwan was depicted, which includes 3 previously reported subgenogroups of C5, B5, and C4, and one C2-like subgenogroup. Based on the phylogenetic analyses using their complete genome nucleotide sequences and neutralization tests, the C2-like subgenogroup forms a genetically distinct cluster from other subgenogroups, and the antisera show a maximum of 128-fold decrease of neutralization titer against this subgenogroup. In addition, the subgenogroup C4 isolates of 2008 were found quite similar genetically to the Chinese strains that caused outbreaks in recent years and thus they should be carefully watched.</p> <p>Conclusions</p> <p>Other than to be the first report describing the existence of C2-like subgenogroup of EV-71 in Taiwan, this article also foresees a potential of subgenogroup C4 outbreaks in Taiwan in the near future.</p
    corecore