18,624 research outputs found

    Learning to Identify Ambiguous and Misleading News Headlines

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    Accuracy is one of the basic principles of journalism. However, it is increasingly hard to manage due to the diversity of news media. Some editors of online news tend to use catchy headlines which trick readers into clicking. These headlines are either ambiguous or misleading, degrading the reading experience of the audience. Thus, identifying inaccurate news headlines is a task worth studying. Previous work names these headlines "clickbaits" and mainly focus on the features extracted from the headlines, which limits the performance since the consistency between headlines and news bodies is underappreciated. In this paper, we clearly redefine the problem and identify ambiguous and misleading headlines separately. We utilize class sequential rules to exploit structure information when detecting ambiguous headlines. For the identification of misleading headlines, we extract features based on the congruence between headlines and bodies. To make use of the large unlabeled data set, we apply a co-training method and gain an increase in performance. The experiment results show the effectiveness of our methods. Then we use our classifiers to detect inaccurate headlines crawled from different sources and conduct a data analysis.Comment: Accepted by IJCAI 201

    Coupling the reduced-order model and the generative model for an importance sampling estimator

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    In this work, we develop an importance sampling estimator by coupling the reduced-order model and the generative model in a problem setting of uncertainty quantification. The target is to estimate the probability that the quantity of interest (QoI) in a complex system is beyond a given threshold. To avoid the prohibitive cost of sampling a large scale system, the reduced-order model is usually considered for a trade-off between efficiency and accuracy. However, the Monte Carlo estimator given by the reduced-order model is biased due to the error from dimension reduction. To correct the bias, we still need to sample the fine model. An effective technique to reduce the variance reduction is importance sampling, where we employ the generative model to estimate the distribution of the data from the reduced-order model and use it for the change of measure in the importance sampling estimator. To compensate the approximation errors of the reduced-order model, more data that induce a slightly smaller QoI than the threshold need to be included into the training set. Although the amount of these data can be controlled by a posterior error estimate, redundant data, which may outnumber the effective data, will be kept due to the epistemic uncertainty. To deal with this issue, we introduce a weighted empirical distribution to process the data from the reduced-order model. The generative model is then trained by minimizing the cross entropy between it and the weighted empirical distribution. We also introduce a penalty term into the objective function to deal with the overfitting for more robustness. Numerical results are presented to demonstrate the effectiveness of the proposed methodology

    On Fleck quotients

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    Let pp be a prime, and let n>0n>0 and rr be integers. In this paper we study Fleck's quotient Fp(n,r)=(βˆ’p)βˆ’βŒŠ(nβˆ’1)/(pβˆ’1)βŒ‹βˆ‘k=r(modp)(nk)(βˆ’1)k∈Z.F_p(n,r)=(-p)^{-\lfloor(n-1)/(p-1)\rfloor} \sum_{k=r(mod p)}\binom {n}{k}(-1)^k\in Z. We determine Fp(n,r)F_p(n,r) mod pp completely by certain number-theoretic and combinatorial methods; consequently, if 2≀n≀p2\le n\le p then βˆ‘k=1n(βˆ’1)pkβˆ’1(pnβˆ’1pkβˆ’1)≑(nβˆ’1)!Bpβˆ’npn(modpn+1),\sum_{k=1}^n(-1)^{pk-1}\binom{pn-1}{pk-1} \equiv(n-1)!B_{p-n}p^n (mod p^{n+1}), where B0,B1,...B_0,B_1,... are Bernoulli numbers. We also establish the Kummer-type congruence Fp(n+pa(pβˆ’1),r)≑Fp(n,r)(modpa)F_p(n+p^a(p-1),r)\equiv F_p(n,r) (mod p^a) for a=1,2,3,...a=1,2,3,..., and reveal some connections between Fleck's quotients and class numbers of the quadratic fields \Q(\sqrt{\pm p}) and the pp-th cyclotomic field \Q(\zeta_p). In addition, generalized Fleck quotients are also studied in this paper.Comment: 28 page

    AT-HOME SEAFOOD CONSUMPTION IN KENTUCKY: A DOUBLE-HURDLE MODEL APPROACH

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    This study investigates demographic and socioeconomic factors contributing to at-home consumption of seafood in Kentucky through a 2010 survey. The Tobit and Cragg’s double-hurdle model are analyzed and tested. Numbers of people in the household, household income, race and employment status are significant determinants of at-home seafood consumption in Kentucky.Food Consumption/Nutrition/Food Safety, Seafood consumption, At-home, Kentucky, Double-Hurdle Model,
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