An Exploratory Study of Hedging in Chinese ESL Learners' Academic

Hedging, referring to the use of various lexical and syntactic features modifying and mitigating propositions and claims, is extensively employed in effective academic writing. However, the use of hedges seems to be quite problematic for lots of Chinese ESL learners. In view of the situation, this study explores the use of hedges in academic abstracts by a group of undergraduate English majors in a university in Hainan Province. After analyzing data from a corpus and interviews, several problems have been found in the use of hedging devices of these students, and relevant implications have been drawn to the teaching of hedging in the context, which can help the students produce more effective academic writing and to achieve greater university success.

COVID‑19 pandemic and the crude oil market risk:hedging options with non‑energy financial innovations

This study examines the hedging effectiveness of financial innovations against crude oil investment risks,both before and during the COVID-19 pandemic.We focus on the non-energy exchange traded funds(ETFs)as proxies for financial innovations given the potential positive correlation between energy variants and crude oil proxies.We employ a multivariate volatility modeling framework that accounts for important statistical features of the non-energy ETFs and oil price series in the computation of optimal weights and optimal hedging ratios.Results show evidence of hedging effectiveness for the financial innovations against oil market risks,with higher hedging performance observed during the pandemic.Overall,we show that sectoral financial innovations provide resilient investment options.Therefore,we propose that including the ETFs in an investment portfolio containing oil could improve risk-adjusted returns,especially in similar financial crisis as witnessed during the pandemic.In essence,our results are useful for investors in the global oil market seeking to maximize risk-adjusted returns when making investment decisions.Moreover,by exploring the role of structural breaks in the multivariate volatility framework,our attempts at establishing robustness for the results reveal that ignoring the same may lead to wrong conclusions about the hedging effectiveness.

Hedging in Discourse Analysis

In this article an attempt to enhance the awareness of hedging use in discourse analysis and academic writing is madeby analyzing hedges employed in two comparable texts.The discourse analysis is conducted from"content-oriented"hedges and"reader-oriented"hedges.The article suggests that hedging can dampen utterances and statements,weaken the force of what onesays and show politeness to the listeners or readers,which varies from different discourse styles of various genres.discourse marker;hedging;research article;news

The Relative Ordering of Optimal Hedging Points in a Class of Failure Prone Manufacturing Systems

For a class of manufacturing systems with homogeneous Markov machine failure rates,the stationary probability distribution of the part surplus can be calculated for given tentative values of hedging points. Some properties on the ordering of optimal hedging points are obtained.

Mean-Variance Hedging for General Claims in an Incomplete Market: Numeraire Method

This paper considered the problem of hedging a European call (put) option for a diffusion model where the asset price is influenced by n uncertain factors. The market is thus incomplete implying that perfect hedging is not possible. To derive a hedging strategy, it follows the approach based on the idea of hedging under a mean-variance criterion suggested by Schweizer. A very simple solution of this hedging problem by using the numeraire method was presented and some examples with explicit solutions were given.

On discrete time hedging errors in a fractional Black-Scholes model

In this paper we investigate asymptotic behavior of error of a discrete time hedging strategy in a fractional Black-Scholes model in the sense of Wick-ItS-Skorohod integration. The rate of convergence of the hedging error due to discrete-time trading when the true strategy is known for the trader, is investigated. The result provides new statistical tools to study and detect the effect of the long-memory and the Hurst parameter for the error of discrete time hedging.

Insiders' Hedging for Jump Diffusion Processes with Applications to Index Tracking

The hedging problem for insiders is very important in the financial market.The locally risk minimizing hedging was adopted to solve this problem.Since the market was incomplete,the minimal martingale measure was chosen as the equivalent martingale measure.By the F-S decomposition,the expression of the locally risk minimizing strategy was presented.Finally,the local risk minimization was applied to index tracking and its relationship with tracking error variance (TEV)-minimizing strategy was obtained.

Option Pricing and Hedging under a Markov Switching Lévy Process Model

In this paper, we consider a Markov switching Lévy process model in which the underlying risky assets are driven by the stochastic exponential of Markov switching Lévy process and then apply the model to option pricing and hedging. In this model, the market interest rate, the volatility of the underlying risky assets and the N-state compensator,depend on unobservable states of the economy which are modeled by a continuous-time Hidden Markov process. We use the MEMM(minimal entropy martingale measure) as the equivalent martingale measure. The option price using this model is obtained by the Fourier transform method. We obtain a closed-form solution for the hedge ratio by applying the local risk minimizing hedging.

Power Purchase Model of Provincial Grids Based on Diverse Energy Coordination Hedging Optimization

Under the background of energy conservation, the grid companies should give priority to consumptive hydropower, wind power and other clean electricity to fulfill their social responsibility and promote the carbon emission reduction in power industry. But under the current power purchase mode, grid companies must first perform the contract. This is extremely uneconomical and not environmentally friendly. Based on hedging theory, this paper proposes a power purchase optimization model using the strategy of “compression and compensation”. If outer price is lower than the contract price, the grid can compress contract power appropriately, leaving more space for purchasing electricity;if outer price is not attractive enough, the grid should timely improve contract proportion, compensating the deviations of contract caused by "compression". Based on the strategy of "compression and compensation", it can effectively reduce the abandoned wind and water, enhance the economic and social benefits of provincial power grid.

Optimal Hedging Strategies of Stock Index Futures Based on the Perspective of Information Asymmetry

Based on two different risk measurement criteria, this article studied the optimal hedging strategies of stock index futures in the case of asymmetric information, and discussed the influence of insider information on the hedging effect. Through simulation analysis, it can be shown that hedging people with insider information can save hedging costs to a certain extent, which also explains the reason why investors try to obtain corporate information in actual investment activities.

A Comparative Study of Scientific Hedging by Chinese Writers and English Writers

Based on a corpus of 10 texts in material science discipline, this paper explores the use of scientific English hedging both by Chinese and English writers. The result shows that there are similarities as well as differences in hedging frequency and distribution between the research articles by Chinese writers and native English writers. Research articles written by Chinese writers tend to be more direct and authoritative in tone as a result of higher frequency of approximators and lower frequency of plausibility shields.

Hedging Devices used in the Opinion Column'S Editorials of China Daily

The editorials of the opinion column in a newspaper express the view of its editors. The application of hedging devices isemployed, in order to support the writers' writing. In this study, the data were gathered from 15 editorials in the opinion column ofChina Daily: 5 editorials are about world issues, the other 5 editorials about Chinese social life, and the last 5 editorials are the edu-cational issues popularly discussed in China. The categorization of hedging devices draws from salvager-Meyer's paper Hedges and Textual Communicative Function in Medical English Written Discourse(1994, p. 154) and Mojica(2005, p. 3). Results revealed thatmost writers of the editorials opted to use approximators and modals. Furthermore, the hedging devices used in the selected editori-als on China Daily mainly had three functions: Show respects of the people or organization or in order for protection; in order to pub-lish timely; and make the prediction more reliable. In general, the Chinese writers seem to be conscious to use hedges appropriatelyin order to make their writing more reliable and avoid some arguments or disparagement.

Hedging in English Academic Papers in Linguistics Written by Chinese Authors

Hedges in academic writing are drawn attention by scholars. Hedging devices enable writers to express their uncertainty con-cerning the factuality of their statements or to indicate deference to their readers. In this paper,ten English linguistic academic articles written by Chinese scholars were chosen for the study. Hedges were categorized to four types. The analysis showed the total number of hedges per category in all articles. The results indicated that modals/probabilities and semi-auxiliaries or epistemic verbs were preferred by Chinese linguists. It is suggested that for non-native English speakers mastery of hedging devices is requisite in their graduate programs.

A Corpus-based Contrastive Study on Hedging in English Business Cor-respondences between Chinese English Learners and Native Speakers

This is a corpus-based contrastive study projected to find out the differences in using hedges in English business corre spondences between Chinese English learners and native speakers.

Convergence and optimality of BS-type discrete hedging strategy under stochastic interest rate

We focus on the asymptotic convergence behavior of the hedging errors of European stock option due to discrete hedging under stochastic interest rates. There are two kinds of BS-type discrete hedging differ in hedging instruments: one is the portfolio of underlying stock, zero coupon bond, and the money market account (Strategy BSI); the other is the underlying stock, zero coupon bond (Strategy BSII). Similar to the results of the deterministic interest rate case, we show that convergence speed of the discounted hedging errors is 1/2-order of trading frequency for both strategies. Then, we prove each of the BS-type strategy is not only locally optimal, but also globally optimal under the corresponding measure. Finally, we give some numerical examples to illustrate the results. All the discussion is based on non-arbitrage condition and zero transaction cost.

Good deal hedging and valuation under combined uncertainty about drift and volatility

We study robust notions of good-deal hedging and valuation under combined uncertainty about the drifts and volatilities of asset prices.Good-deal bounds are determined by a subset of risk-neutral pricing measures such that not only opportunities for arbitrage are excluded but also deals that are too good,by restricting instantaneous Sharpe ratios.A non-dominated multiple priors approach to model uncertainty(ambiguity)leads to worst-case good-deal bounds.Corresponding hedging strategies arise as minimizers of a suitable coherent risk measure.Good-deal bounds and hedges for measurable claims are characterized by solutions to secondorder backward stochastic differential equations whose generators are non-convex in the volatility.These hedging strategies are robust with respect to uncertainty in the sense that their tracking errors satisfy a supermartingale property under all a-priori valuation measures,uniformly over all priors.

Static Hedging with Uncertain Quantity and Departure from the Cost-of-Carry Valuation

In this paper, we are concerned with the optimal hedge ratio under quantity risk as well as discrepancies between the futures market price and its theoretical valuation according to the cost- of-carry model. Assuming a geometric Brownian motion for forecasting process, we model mispricing as a specific noise corn poncnt in the dynamics of filturcs market prices, based on which the optimal hedging strategy is calculated. Finally, we illustrate optimal strategy and its properties by numerical examples.

How Fast Does It Diverge? Discrete Hedging Error with Transaction Costs

In the present paper,we focus on the diverging behavior of discrecte hedging error with transaction costs.We added the hedging cost to the error directly.The main idea is to divide the hedging error into two parts:the pure hedging error and transaction cost of rebalance.The later part will be diverged when hedging number n goes to infinity.Firstly we show an upper bound of diverging part,which is O(√n)of rebalancing number n,then we prove both the upper bound and the lower bound of discrete hedging error with transaction costs are of√n order,finally we give an approximation of hedging error to determine the coefficient in front of√n.The main technique in the proof is Itô’s formula,L’Hopital’s rule and three important lemmas in[Yuri,Kabanov,Mher,Safarian.Markets with Transaction Costs.Springer-Verlag,Berlin,Heidelberg,2009].The numerical result support our theoretical conclusion.

EXPLICIT EXPRESSIONS FOR THE VALUATION AND HEDGING OF THE ARITHMETIC ASIAN OPTION

On the basis of a result in Yor (1992), this paper gives explicit expressions for the valuation and hedging of the arithmetic Asian option.

Application of Modified Progressive Hedging for Stochastic Unit Commitment in Electricity-Gas Coupled Systems

The increasing number of gas-fired units has significantly intensified the coupling between electric and gas power networks.Traditionally,nonlinearity and nonconvexity in gas flow equations,together with renewable-induced stochasticity,resulted in a computationally expensive model for unit commitment in electricity-gas coupled integrated energy systems(IES).To accelerate stochastic day-ahead scheduling,we applied and modified Progressive Hedging(PH),a heuristic approach that can be computed in parallel to yield scenario-independent unit commitment.Through early termination and enumeration techniques,the modified PH algorithm saves considerable com,putational time for certain generation cost settings or when the scale of the IES is large.Moreover,an adapted second-order cone relaxation(SOCR)is utilized to tackle the nonconvex gas flow equation.Case studies were performed on the IEEE 24.bus system/Belgium 20-node gas system and the IEEE 118-bus system/Belgium 20-node gas system.The computational efficiency when employing PH is 188 times that of commercial software,and the algorithm even outperforms Benders Decomposition.At the same time,the gap between the PH algorithm and the benchmark is less than 0.01% in both IES systems,which proves that the solutions produced by PH reach acceptable optimality in this stochastic UC problem.