An investigation of the attention effects of venture capitalist backing on entrepreneurial firms

In this paper, we predict that venture capital (VC) backed initial public offerings (IPOs) will attract more attention than non-VC-backed IPOs, as VCs offer important signals to investors searching for information about entrepreneurial firms. We use a measure developed by Google (i.e., Trends) to capture the spikes in investors' attention experienced by firms in the time period surrounding their IPOs. Our results demonstrate that firms backed by VCs enjoy a far greater spike in attention than their counterparts. Furthermore, we find that firms with more prominent VCs, a larger number of VCs, and VCs situated at farther geographic distances exhibit significantly greater spikes in investors’ attention during the week of their IPO. Combined, the findings show a clear demarcation between entrepreneurial firms with or without VC backing, they bring to the fore new upshots stemming from the relationship between VCs and entrepreneurial firms, and they raise new potential questions on this relationship and beyond.     

An MEP.2 plan in 3 factorial experiment and its probability of correct identification

The present work consider the problem of constructing search designs for searching at most two active hidden two-factor interactions in 3ⁿ factorial setup under the assumption that the three-factor and higher-order interactions are negligible. The designs presented here are also capable of estimating all the main effects, general mean and the effects of identified active two-factor interactions. The performance of the designs has been studied in the noisy case by computing probability of correct identification.     

消费者搜寻信息努力与影响因素的实证研究——以广告媒体为中心

结果表明,在被假设的广告媒体搜寻信息努力与五个影响因素之间的关系中,四个因素即搜寻态度(+)、自我卷入(+)、产品知识(-)、时间压力(-)与广告媒体搜寻信息努力之间有关系。而消费者感知风险与广告媒体搜寻信息努力之间没有关系。     

Minimizing the expected time to detect a randomly located lost target using 3-dimensional search technique

Abstract

This paper considers a new model in search theory to find a randomly located target in the 3-dimensional space. An approximation algorithm that facilitates searching procedures for searchers or robots is presented. The expected time to detect the target is also proved. The statistical analysis by calculating the optimal search strategy which minimizes the time to detect the target, assuming trivariate standard normal distribution is provided, and the technique by flowcharts is designed as well. The effectiveness of this strategy is illustrated by introducing an application from real world.     

基于机器学习LSTM&US模型的消费者信心指数预测研究

消费者信心指数等宏观经济指标具有时间上的滞后效应和动态变化的多维性,不易精确预测。本文基于机器学习长短时间记忆(Long Short-Term Memory,LSTM)神经网络模型,结合大数据技术挖掘消费者信心指数相关网络搜索数据(User Search,US),进而构建一种LSTM&US预测模型,并将其应用于对我国消费者信心指数的长期、中期与短期的预测研究,同时引入多个基准预测模型进行了对比分析。结果发现:引入网络搜索数据能够提高LSTM神经网络模型的预测性能与预测精度;LSTM&US预测模型具有较好的泛化能力,对不同期限的预测效果均较稳定,其预测性能与预测精度均优于其他六种基准预测模型(LSTM、SVR&US、RFR&US、BP&US、XGB&US和LGB&US);预测结果显示本文提出的LSTM&US预测模型具有一定的实用价值,该预测方法为消费者信心指数的预测与预判提供了一种新的研究思路,丰富了机器学习方法在宏观经济指标预测领域中的理论研究。     

The VL control measure for symmetric networks

In this paper we measure “control” of nodes in a network by solving an associated optimisation problem. We motivate this so-called VL control measure by giving an interpretation in terms of allocating resources optimally to the nodes in order to maximise some search probability. We determine the VL control measure for various classes of networks. Furthermore, we provide two game theoretic interpretations of this measure. First it turns out that the VL control measure is a particular proper Shapley value of the associated cooperative network game. Secondly, we relate the measure to optimal strategies in an associated matrix search game.     

西夏文“■■”(b■2bjij1)考源

西夏文“■■”(b■²bjij¹)又写作“■■”(b■²bjij¹),常见于佛经文献,与汉文本“粪扫(衣)”“补衲(衣)”等对译。从字形和字音两方面进行考察,依据出土的西夏文献材料,推测该词在西夏文造字时与“■■”(b■²bjij¹)同源,意为“蜣螂”。蜣螂以粪便为食,有喜于粪土中推却屎丸的习性,后来,人们用该词专门记录佛经中的“粪扫(衣)”“粪(衣)”,成为佛经专用词。“粪扫衣”又称“衲衣”“百衲衣”,为世俗人当做垃圾舍弃的衣服,泛指僧尼所穿之僧衣。又因僧尼的衣服多补缀缝衲而成,因此西夏文献中的“■■”(b■²bjij¹)又衍生出动词“补衲”、名词“补丁”和形容词“破旧的”等义项。     

The permutation flow shop problem with just in time production considerations

This research presents a variation to the permutation flow shop problem where Just In Time (JIT) production requirements are taken into account. The model developed in this research employs dual objectives. In addition to the traditional objective of minimizing the production makespan, minimization of Miltenburg's material usage rate is also incorporated. In this model, multiple units of any product are permitted in the production sequence. However, the minimization of material usage rates attempts to prevent batch scheduling of products and allows unit flow of products as required in demand flow manufacturing. A solution method is proposed for determining an optimal production sequence via an efficient frontier approach and Simulated Annealing (SA). Test problems and specific performance criteria are used to assess the solutions generated by the proposed method. Experimental results presented in this paper show that the use of the efficient frontier and SA provide solutions that approach the optimal solution for the performance measures used in this research.     

An efficient tabu search algorithm for the single- machine mean tardiness problem

In this paper, an efficient tabu search algorithm is prepared for solving the single-machine mean tardiness problem. The proposed implementation of the tabu search approach suggests simple techniques for generating neighbourhoods of a given sequence and a combined scheme for intensification and diversification. The tabu search method is shown to produce results very close to the optimal solution using randomly generated problems with varying degrees of difficulty.     

An Empirical Equilibrium Model of a Decentralized Asset Market

I estimate a search‐and‐bargaining model of a decentralized market to quantify the effects of trading frictions on asset allocations, asset prices, and welfare, and to quantify the effects of intermediaries that facilitate trade. Using business‐aircraft data, I find that, relative to the Walrasian benchmark, 18.3 percent of the assets are misallocated; prices are 19.2 percent lower; and the aggregate welfare losses equal 23.9 percent. Dealers play an important role in reducing trading frictions: In a market with no dealers, a larger fraction of assets would be misallocated, and prices would be higher. However, dealers reduce aggregate welfare because their operations are costly, and they impose a negative externality by decreasing the number of agents' direct transactions.