Search results for "Rankin"
showing 10 items of 259 documents
Network Centralities and Node Ranking
2017
An important problem in network analysis is understanding how much nodes are important in order to “propagate” the information across the input network. To this aim, many centrality measures have been proposed in the literature and our main goal here is that of providing an overview of the most important of them. In particular, we distinguish centrality measures based on walks computation from those based on shortest-paths computation. We also provide some examples in order to clarify how these measures can be calculated, with special attention to Degree Centrality, Closeness Centrality and Betweennes Centrality.
Learning to Rank Images for Complex Queries in Concept-based Search
2018
Concept-based image search is an emerging search paradigm that utilizes a set of concepts as intermediate semantic descriptors of images to bridge the semantic gap. Typically, a user query is rather complex and cannot be well described using a single concept. However, it is less effective to tackle such complex queries by simply aggregating the individual search results for the constituent concepts. In this paper, we propose to introduce the learning to rank techniques to concept-based image search for complex queries. With freely available social tagged images, we first build concept detectors by jointly leveraging the heterogeneous visual features. Then, to formulate the image relevance, …
k-Truss Decomposition for Modular Centrality
2018
There is currently much interest in identifying influential spreaders in complex networks due to many applications concerned, such as controlling the outbreak of epidemics and conducting advertisements for commercial products, and so on. A plethora of centrality measures have been proposed over the years based on the topological properties of networks. However, most of these classical centrality measures fail to select the most influential nodes in networks with a modular structure despite that it is an omnipresent property in real-world networks. Few authors have introduced centrality measures tailored to networks with community structure. In a recent work, we have shown that, in this case…
Top-k String Similarity Joins
2020
Top-k joins have been extensively studied in relational databases as ranking operations when every object has, among others, at least one ranking attribute. However, the focus has mostly been the case when the join attributes are of primitive data types (e.g., numerical values) and the join predicate is equality. In this work, we consider string objects assigned such ranking attributes or simply scores. Given two collection of string objects and a string similarity measure (e.g., the Edit distance), we introduce the top-k string similarity join () which returns k sufficiently similar pairs of objects with respect to a similarity threshold ϵ, which have the highest combined score computed by…
QUEXME: A Query Expansion Method Applied to Water Information System
2009
The aim of the paper is to present and apply a QUery EXpansion MEthod called QUEXME while querying the Euro-Mediterranean Information System (EMWIS) on know-how in the Water sector. EMWIS provides a strategic tool for exchanging information and knowledge in the water sector between and within the Euro Mediterranean partnership countries (www.emwis.net). Information retrieval on the web or through some cooperation of information sources or some general knowledge bases is a complex process and a great challenge with the emergence of the semantic web. The aim of the query expansion method is to help and guide users to build their requests giving them some usually related terms close to their q…
Genocide, torture, and terrorism: ranking international crimes and justifying humanitarian intervention
2018
The Best Hedging Strategy in the Presence of Transaction Costs
2009
Considerable theoretical work has been devoted to the problem of option pricing and hedging with transaction costs. A variety of methods have been suggested and are currently being used for dynamic hedging of options in the presence of transaction costs. However, very little was done on the subject of an empirical comparison of different methods for option hedging with transaction costs. In a few existing studies the different methods are compared by studying their empirical performances in hedging only a plain-vanilla short call option. The reader is tempted to assume that the ranking of the different methods for hedging any kind of option remains the same as that for a vanilla call. The …
Ranking world tourist destinations with a composite indicator of competitiveness: To weigh or not to weigh?
2019
Abstract This paper contributes a weighted composite indicator of competitiveness for 136 world tourist destinations. To that end, Data Envelopment Analysis and Multi-Criteria-Decision-Making techniques are used with raw indicators from the 2017 edition of the Travel & Tourism Competitiveness Report of the World Economic Forum (WEF). An outstanding feature of our approach is that weights are endogenously generated. Furthermore, the role played by several variables in tourism competitiveness is assessed using truncated regression and bootstrapping. The ranking of world tourist destinations produced by our weighted composite indicator of competitiveness is, however, fairly similar to that der…
Kayne's model of Case and Finnish nominal phrases
2008
The standard view concerning Case assignment or valuation is that Case is valued to determiner phrases (DPs) in syntax. Recently, Kayne has proposed an alternative model, in which Case is valued to lexical elements rather than to phrases. This article cites several facts from Finnish in support of this model. A detailed Kaynean model of Case is developed. According to this model, abstract Case is valued to lexical elements by the highest ranking c-commanding Case assigner when each phase (CP,vP) is sealed, where ranking is based on a particular Case Hierarchy and a simple notion of locality. Configurations in which Case is seemingly assigned under a spec–head relation are provided with an a…
The effect of climate on Burgundy vintage quality rankings.
2019
Aim: Based on consensus rankings from prominent rating authorities, we examined the importance of a suite of climatic variables, organized by winegrape phenological stage, in distinguishing between high- and low-ranked vintages in Burgundy.Methods and Results: Vintage ratings of Burgundy wines acquired from 12 sources were evaluated to develop consensus rankings for red and white wines from 1961–2015. Climate variables (air temperature, precipitation, degree-day accumulations, etc.) were organized by mean phenological stage and compared between good and poor vintages using Mann-Whitney U tests and multivariate stepwise discriminant function analysis. High temperatures, particularly during t…