Search results for "Volatility"
showing 10 items of 245 documents
COVID-19 Drives Consumer Behaviour and Agro-Food Markets towards Healthier and More Sustainable Patterns
2020
This study examines the extant state of research into our understanding of the impact of the coronavirus pandemic in its early stages on food-purchasing behaviour. As such, it includes a summary and categorisation of the findings, extending to consumption preferences worldwide. After the indiscriminate stockpiling of food, which was witnessed in many countries following the implementation of the lockdown, the impact of COVID-19 (COronaVIrus Disease-2019) on consumer habits has inversely varied in function of personal attitudes, individual and household experiences, and characteristics. Specific contexts, and the financial, economic, and logistic nature of these contexts, have also been foun…
Cone-beam computed tomography in lung stereotactic ablative radiation therapy: predictive parameters of early response
2016
To analyze lung lesion volume variations by contouring on cone-beam CT (CBCT) images to evaluate the early predictive parameters of stereotactic ablative radiation therapy (SABR) treatment response.The prescribed dose of SABR was varied according to the tumour site (central or peripheral) and maximum diameter of the lesions by using a strategy of risk-adapted dose prescription with a dose range between 48 and 70 Gy in 3-10 consecutive fractions. For the purpose of the analysis, the gross tumour volume (GTV) was recontoured for each patient at first and last CBCT using two lung levels/windows: (a) -600/1000 HU and (b) -1000/250 HU. Univariate analysis was performed to evaluate a correlation …
Ethyl Hexanoate Transfer Modeling in Carrageenan Matrices for Determination of Diffusion and Partition Properties.
2007
; Aroma compound properties in food matrices, such as volatility and diffusivity, have to be determined to understand the effect of composition and structure on aroma release and perception. This work illustrates the use of mass transfer modeling to identify diffusion and partition properties of ethyl hexanoate in water and in carrageenan matrices with various degrees of structure. The comparison of results obtained with a diffusive model to those obtained with a convective model highlights the importance of considering the appropriate transfer mechanism. Modeling of the preliminary experimental steps ensures correct estimation of the conditions for the main aroma release step. The obtaine…
Circuit Breakers – a legal analysis of volatility safeguards in the rules of stock exchanges on the occasion of the COVID-19 crisis
2020
Abstract This paper examines circuit breakers (CBs), i. e. emergency systems of trading venues that interrupt or restrain trading when significant price movements of financial instruments occur. After a description of the ratio legis and the economic fundamentals, the genesis and the different forms of CBs are presented. The European legal framework is then outlined. The relevant rules of the Frankfurt Stock Exchange (FWB) serve as an example.
Taxonomic flux as a measure of evolutionary turnover
2021
We introduce a new metric, "taxonomic flux", to quantify evolutionary trends both within and across taxonomic boundaries. This metric is normalized, which reduces the effect of sample size disparity between biologic groups and time intervals. Furthermore, this methodology considers stratigraphic range data as a whole, and measures relative growth or decline of diversity values as they deviate from system stability. Such trends may yield key information relating to evolutionary processes and forcing functions, especially if these trends are correlative within particular taxa or niche occupancy. Thus far, scientists and researchers have been stymied by absolute values derived from unequal dat…
A behavioural finance explanation of speculative bubbles: evidence from the bitcoin price development
2019
In 2008 a group of programmers, alias Satoshi Nakamoto, introduced bitcoin. Bitcoin is a cryptocurrency or virtual money derived from mathematical cryptography and is conceived as an alternative to government authorised currency. The founder anticipated, through bitcoin’s construction and his digital mining processes, that bitcoin prices would be relatively stable. However, the recent bitcoin price decline proves that bitcoin is extraordinarily volatile and is not that stable as hoped. Although some scientists have already shown that the fundamental value of bitcoin is zero, the price of bitcoin has reached over 19.000$ in December 2018. Since then, bitcoin prices dropped nearly 70% from th…
When the Blockchain Does Not Block: On Hackings and Uncertainty in the Cryptocurrency Market
2019
A total of 1.1 million bitcoin were stolen in the 2013–2017 period. Noting that the average price for Bitcoin in 2018 was USD 7,572 the corresponding monetary equivalent of losses is USD 8.9 billion which strongly shows the societal impact of this criminal activity. Investigating the response of the uncertainty of Bitcoin when hacking incidents occur, the results of this study point toward a delayed response in volatility. The volatility increases significantly only at day t+5. Incidents of hacking that occur in the Bitcoin market affect uncertainty for another cryptocurrency Ethereum too. Again, the evidence suggests a delayed response. However, Bitcoin and Ethereum do not exhibit asymmetr…
Intrinsic value in crypto currencies
2021
Abstract Over the last years, cryptocurrencies have acquired a growing social and economic interest. The most representative features of this new phenomenon are strong price increases and high volatility. The investigations developed in this field are not excessively numerous nor unanimous. Some researches consider this phenomenon to be a bubble, since they don't agree that the price pattern of the cryptocurrencies is justified or explained by their intrinsic value. The present article aims to provide a theoretical framework for the assessment of these new realities embodied by cryptocurrencies. We have created a model which differentiates two types of cryptocurrencies: the cryptocurrencies…
DECLINE IN US OUTPUT GROWTH VOLATILITY: A WAVELET ANALYSIS*
2012
The aim of the paper is to determine (endogenously) whether the volatility of the US output growth rate has changed since the late 1940s. By applying the discrete wavelet transform to the annualized quarter-to-quarter output growth series, we test the homogeneity of the variance on a scale-by-scale basis. A version of the Normalized and Centered Cumulative Sum of Squares test, adapted to wavelets, leads us to reject the null of constant variance in the two levels of decomposition of the highest resolution and to locate a single break in 1982. The economic implications are explored.
How fair-value accounting can influence firm hedging
2012
Published version of an article in the journal: Review of Derivatives Research. Also available from the publisher at: http://dx.doi.org/10.1007/s11147-012-9084-y The potential influence of accounting regulations on hedging strategies and the use of financial derivatives is a research topic that has attracted little attention in both the finance and the accounting literature. However, recent surveys suggest that company hedging can be substantially influenced by the accounting for financial instruments. In this study, we illustrate not only why but also how the accounting regulations may affect hedging behavior. We find that under mark-to-market accounting, most firms concerned with earnings…