Search results for "tail"
showing 10 items of 702 documents
A computational proposal for a robust estimation of the Pareto tail index: An application to emerging markets
2022
Abstract In this work, we backtest and compare, under the VaR risk measure, the fitting performances of three classes of density distributions (Gaussian, Stable and Pareto) with respect to three different types of emerging markets: Egypt, Qatar and Mexico. We also propose a new technique for the estimation of the Pareto tail index by means of the Threshold Accepting (TAVaR) and the Hybrid Particle Swarm Optimization algorithm (H-PSOVaR). Furthermore, we test the accuracy and robustness of our estimates demonstrating the effectiveness of the proposed approach.
Joint route planning under varying market conditions
2007
PurposeTo provide empirical evidence on the level of savings that can be attained by joint route planning and how these savings depend on specific market characteristics.Design/methodology/approachJoint route planning is a measure that companies can take to decrease the costs of their distribution activities. Essentially, this can either be achieved through horizontal cooperation or through outsourcing distribution to a logistics service provider. The synergy value is defined as the difference between distribution costs in the original situation where all entities perform their orders individually, and the costs of a system where all orders are collected and route schemes are set up simulta…
Brand stores' functions : an approach through brand experience
2022
In-store brand experience leverages brand equity and customer equity which are clear value sources for brands (literature review and exploratory studies). The experience quality is linked to its capacity to meet these goals. Compared to generalist distributors and multi-brand experiences, brand stores are dedicated and focused. They are key places since service and experience items are crafted by the brand itself. The brand is therefore able to grant a genuine, i.e., authentic brand experience (brand content recognition and brand authentication through in-store experience). It is less the case in its distributors’ stores, where brand experience competes with its competitors’ and its distrib…
Observing animals and humans : dogs target their gaze to the biological information in natural scenes
2020
Background This study examines how dogs observe images of natural scenes containing living creatures (wild animals, dogs and humans) recorded with eye gaze tracking. Because dogs have had limited exposure to wild animals in their lives, we also consider the natural novelty of the wild animal images for the dogs. Methods The eye gaze of dogs was recorded while they viewed natural images containing dogs, humans, and wild animals. Three categories of images were used: naturalistic landscape images containing single humans or animals, full body images containing a single human or an animal, and full body images containing a pair of humans or animals. The gazing behavior of two dog populations,…
Probabilistic entailment in the setting of coherence: The role of quasi conjunction and inclusion relation
2013
In this paper, by adopting a coherence-based probabilistic approach to default reasoning, we focus the study on the logical operation of quasi conjunction and the Goodman-Nguyen inclusion relation for conditional events. We recall that quasi conjunction is a basic notion for defining consistency of conditional knowledge bases. By deepening some results given in a previous paper we show that, given any finite family of conditional events F and any nonempty subset S of F, the family F p-entails the quasi conjunction C(S); then, given any conditional event E|H, we analyze the equivalence between p-entailment of E|H from F and p-entailment of E|H from C(S), where S is some nonempty subset of F.…
Generalized Logical Operations among Conditional Events
2018
We generalize, by a progressive procedure, the notions of conjunction and disjunction of two conditional events to the case of n conditional events. In our coherence-based approach, conjunctions and disjunctions are suitable conditional random quantities. We define the notion of negation, by verifying De Morgan’s Laws. We also show that conjunction and disjunction satisfy the associative and commutative properties, and a monotonicity property. Then, we give some results on coherence of prevision assessments for some families of compounded conditionals; in particular we examine the Frechet-Hoeffding bounds. Moreover, we study the reverse probabilistic inference from the conjunction $\mathcal…
Vertical Separation v. Independent Downstream Entry in the Spanish Electricity Network: An Experimental Approach
2007
We present experimental results from a series of sessions organized using the Power Market simulator; a software designed to realistically replicate the Spanish Electricity Market. In the experiments reported here we compare the status quo to two alternative treatments which represent alternative market structures. In one of them, labeled as vertical separation, we assume that power generating firms and electricity distributors-endsuppliers belong to separate business groups. In the second, we study the effect of entry by independent end-suppliers. Both alternative scenarios dominate the status quo in terms of market efficiency, whereas the latter of them dominates the former.
Income structure, profitability and risk in the European banking sector: The impact of the crisis
2017
This study sets out to analyse whether the effect of the income structure on the risk and profitability of European banks has changed as a result of the crisis and if it varies according to banks’ specialisation in a particular type of banking business. To do so, it estimates the income structure over the period 2002–2012 using data for a panel of European banks. The study also examines if there are differences between investment-oriented banks and banks specialising in financial intermediation in terms of the effect of income structure on risk and profitability. Our findings show that an increase in the share of non-interest income has a negative impact on profitability, although the effec…
Risk Management for Sovereign Financing within a Debt Sustainability Framework
2018
The mix of instruments used to finance a sovereign is a key determinant of debt sustainability through its effect on funding costs and risks. We extend standard debt sustainability analysis to incorporate debt-financing decisions in the presence of macroeconomic, financial, and fiscal risks. We optimize the maturity of debt instruments to trade off borrowing costs with refinancing risk. Risk is quantified with a coherent measure of tail risk of financing needs, conditional Flow-at-Risk. A constraint on the pace of reduction of debt stocks is also imposed, and we model the effect of debt stocks on the yield curve through endogenous risk and term premia. On a simulated economy, we show that t…
On the Tail Risk of Cyberattacks in the Bitcoin Market
2020
In the era of digitalization, cryptocurrencies have become an alternative asset for both retail and institutional investors. While the new emerging digital ecosystem based on blockchain technology has been praised for offering plenty of advantages such as decentralization, discretion or increased efficiency in terms of faster settlements among others, investors need to be aware of new types of risks such as hacking incidents. In the 2011-2018 period, about 1.7 million unit of Bitcoin have been stolen corresponding to losses accumulating more than $655 million highlighting the societal impact of this criminal activity. The novel aspect of our study is that it employs a recently proposed appr…