New lower bounds for the second variable Zagreb index

The aim of this paper is to obtain new sharp inequalities for a large family of topological indices, including the second variable Zagreb index \(M_2^{\alpha }\), and to characterize the set of extremal graphs with respect to them. Our main results provide lower bounds on this family of topological indices involving just the minimum and the maximum degree of the graph. These inequalities are new even for the Randi?, the second Zagreb and the modified Zagreb indices.     

Multiple hypernode hitting sets and smallest two-cores with targets

The multiple weighted hitting set problem is to find a subset of nodes in a hypergraph that hits every hyperedge in at least m nodes. We extend the problem to a notion of hypergraphs with so-called hypernodes and show that, for m=2, it remains fixed-parameter tractable (FPT), parameterized by the number of hyperedges. This is accomplished by a nontrivial extension of the dynamic programming algorithm for hypergraphs. The algorithm might be interesting for certain assignment problems, but here we need it as a tool to solve another problem motivated by network analysis: A d-core of a graph is a subgraph in which every vertex has at least d neighbors. We give an FPT algorithm that computes a smallest 2-core including a given set of target vertices, where the number of targets is the parameter. This FPT result is best possible in the sense that no FPT algorithm for 3-cores can be expected.     

Authenticity: Meanings,targets, audiences and third parties

Research shows that perceived authenticity conveys value in many disparate domains. The analytical attention of this research focuses on producers of products and services, identifying which actions and structures the typical individual associates with authenticity. Far less is known about how individuals and audiences differ in their interest, receptiveness and response to potentially authentic entities and services. Even less is known about how regulators, certifiers, critics and other third parties play a role in the social construction of authenticity. Yet the perception and valuation of a product or service as authentic rests largely with heterogeneous audiences and interpretive third parties. Accordingly, in this chapter, we review and develop theory and empirical research about how targeted entities (producers, persons, products, services), audiences and third parties combine to produce authenticity. For targets, we examine the range of actions and structures of various entities that have been empirically associated with authenticity. For audiences, we explore variations in interests in authenticity based on domain engagement, cosmopolitanism, and cross-cultural differences. For third parties, we consider the roles of other audience members, certifiers and regulators. Finally, we conceptualize a co-evolutionary process whereby targets, audiences and third parties combine to generate social pockets where authenticity is recognized and highly valued.     

Why textile and clothing industries are shifting to the third world

The 1970s witnessed important changes in the international division of industrial labour. Textiles and clothing were the major examples of industries where comparative advantage shifted in favour of developing countries. The present article discusses the reasons why textiles and clothing are important at the early stage of industrialization. It then examines the statistical relationship between the size of these industries and GNP per capita levels and finds this to be strongly negative. The article concludes that this points to the unrealistic nature of developed countries' attempts to maintain textile and clothing industries at their present size through protectionism, and that this will be an inadequate response to future changes in the international division of labour.     

Online leasing problem with price fluctuations under the consumer price index

We present a \((20+{5}/{n})\)-approximation algorithm for the non-uniform soft capacitated k-facility location problem, violating the capacitated constrains by no more than a factor of 25. The main technique is based on the primal–dual algorithm for the soft capacitated facility location problem, and the exploitation of the combinatorial structure of the fractional solution for the soft capacitated k-facility location problem.     

On maximum Wiener index of trees and graphs with given radius

Let G be a connected graph of order n. The long-standing open and close problems in distance graph theory are: what is the Wiener index W(G) or average distance \(\mu (G)\) among all graphs of order n with diameter d (radius r)? There are very few number of articles where were worked on the relationship between radius or diameter and Wiener index. In this paper, we give an upper bound on Wiener index of trees and graphs in terms of number of vertices n, radius r, and characterize the extremal graphs. Moreover, from this result we give an upper bound on \(\mu (G)\) in terms of order and independence number of graph G. Also we present another upper bound on Wiener index of graphs in terms of number of vertices n, radius r and maximum degree \(\Delta \), and characterize the extremal graphs.     

情绪指数与市场收益: 纳入中国波指( iVX) 的分析

本文在 Baker 和 Wurgler( 2006, 2007) 研究框架的基础上, 将中国波动率指数( iVX) 作为一个新的情绪代理变量,结合传统的封闭式基金折价率、股票换手率和 IPOs 的数量等变量,运用主成分分析法构建了中国 A 股市场的情绪指数, 并分析了情绪指数与市场收益之间的依赖关系和预测效果． 研究发现,情绪指数与市场收益呈负向关系． 然而,其当期依赖关系并不显著,而情绪指数对其后第三周的市场收益有较显著的负向预测关系． 中国波指的加入能够明显提高这种预测效果; 相反,IPOs 的数量则并不是一个有效的情绪代理变量． 此外, 采用前两个主成分的加权并不比仅采用第一主成分构建情绪指数在市场收益预测方面表现得更好, 甚至表现得更差． 最后,分析了情绪效应的不对称性,发现正情绪指数对未来收益的影响要远远大于负情绪指数．     

生存分析与股指涨跌的概率推断

通过研究上证指数连涨连跌的收益率,发现其服从伽玛分布,并且可得出股指涨跌的条件概率,以及极值时的情况,进一步研究了成交量的影响,从而说明了技术分析特别是价量分析为何在实际中仍然被广泛运用.可认为随机游动假说是一种粗糙的近似,本研究也有助于加深对市场有效性理论的认识.     

An aggregate index for the analysis of productivity and profitability

Many measures have been devised for assessing economic performance in industry and business, but there is no systematic formula for integrating productivity and profitability, the effect of scale of production and the effect of technical change. This paper examines the factors which underlie the performance of economic activity and proposes an aggregate index number for the purpose. Experience from actual applications shows that the formula proposed is applicable at the level of industry and even of the firm.     

Intraday pricing of ETFs and certificates replicating the German DAX index

The market for the leading German equity index DAX comprises electronically traded futures contracts, fully replicated and swap-based exchange-traded funds (ETFs), and certificates. This paper reveals that DAX futures contracts contribute an economically and statistically significant proportion to contemporaneous price quotes of ETFs and certificates. This finding is surprising because the prospectus of ETFs and certificates claim to follow the stock index solely, but not the index futures contract. Exploring further the short-run dynamics, our results suggest that fully replicated ETFs cope better with adjusting their prices to the DAX index than swap-based ETFs and certificates.     

On the relation between Wiener index and eccentricity of a graph

Journal of Combinatorial Optimization - The relation between the Wiener index W(G) and the eccentricity $$\varepsilon (G)$$ of a graph G is studied. Lower and upper bounds on W(G) in terms of...     

The game chromatic index of some trees with maximum degree four and adjacent degree-four vertices

A (proper) total-k-coloring of a graph G is a mapping \(\phi : V (G) \cup E(G)\mapsto \{1, 2, \ldots , k\}\) such that any two adjacent or incident elements in \(V (G) \cup E(G)\) receive different colors. Let C(v) denote the set of the color of a vertex v and the colors of all incident edges of v. An adjacent vertex distinguishing total-k-coloring of G is a total-k-coloring of G such that for each edge \(uv\in E(G)\), \(C(u)\ne C(v)\). We denote the smallest value k in such a coloring of G by \(\chi ^{\prime \prime }_{a}(G)\). It is known that \(\chi _{a}^{\prime \prime }(G)\le \Delta (G)+3\) for any planar graph with \(\Delta (G)\ge 10\). In this paper, we consider the list version of this coloring and show that if G is a planar graph with \(\Delta (G)\ge 11\), then \({ ch}_{a}^{\prime \prime }(G)\le \Delta (G)+3\), where \({ ch}^{\prime \prime }_a(G)\) is the adjacent vertex distinguishing total choosability.     

Measurement and decomposition of the Malmquist productivity index for parallel production systems

The conventional Malmquist productivity index (MPI), which ignores the internal structure of a production system when measuring changes in performance between two periods, may produce misleading results. This paper thus takes the operations of the component processes into account in investigating the MPI of parallel production systems. A relational data envelopment analysis (DEA) model is developed to measure the biennial MPIs of the system and internal processes at the same time, and it is shown that the former is a linear combination of the latter. This decomposition helps identify the processes that cause the decline in performance of the system. An example of 39 branches of a commercial bank, with deposits, sales, and services as the three major functions operating in parallel, is used to illustrate this approach.