A measure of the variability of a market factor, most often the price of the underlying instrument. Volatility is defined mathematically as the annualised standard deviation of the natural log of the ratio of two successive prices. The actual volatility realised over a period of time (the historical volatility) can be calculated from recorded data.
Volatility is one of the variables that must be specified in the Black-Scholes model of option pricing: a vanilla option will cost more when volatility is high than when it is low. However, volatility is the only one of these variables whose value must be estimated.
The estimate used (known as the implied volatility) can be derived from the prices of options in the market and the known input variables. However, the Black-Scholes model also assumes that volatility is constant, which is not true. New techniques have been developed to cope with volatility’s variability, including mean-reverting models (such as Garch) and stochastic volatility models.
* see also Black-Scholes model; Garch
The Energy Risk Glossary, now in its eighth edition, provides an at-a-glance explanation of the myriad specialised terms and acronyms used in energy trading and risk management.
This year, the guide has been updated by Aviv Handler of ETR Advisory. Energy Risk would like to thank him for his input into this edition, which benefits greatly from his valuable experience and insight into energy markets.
The fast-changing nature of these markets means much has changed since our last edition – almost 200 new entries and revisions have been made this year. Reflecting the increasing importance of regulation, definitions of the Markets in Financial Instruments Directive (MiFid) and the Ljubljana-based Agency for the Cooperation of Energy Regulators (Acer) make it into the glossary for the first time. A focus on improving back-office infrastructure and mitigating counterparty risk is also apparent from the inclusion of terms such as ‘portfolio reconciliation’ and ‘portfolio compression’.
The glossary is extensively cross-referenced, making for easy and thorough searches. We hope you find it useful.
More on Risk Management
Debt has jumped fifty-fold at Eskom as it races to build new power stations
We consider the class of risk measures associated with optimized certainty equivalents. This class includes several popular examples, such as conditional value-at-risk (CVaR) and monotone mean-variance....
Capital allocation principles are used in various contexts in which the risk capital or the cost of an aggregate position has to be allocated between its constituent parts. We study capital allocation...
The presence of options in a portfolio fundamentally alters the portfolio's risk and return profiles when compared with an all-equity portfolio. In this paper, we advocate modeling a risk-based criterion...
Sign up for Risk.net email alerts
Research chief is sceptical about end of oil indexation in European gas
Mexico's energy reform may lead to closer ties with adjacent US states
Swap dealers playing a guessing game while complying with CFTC rules
Bill Perkins believes rising demand and reduced risk warehousing will create opportunities for natural gas traders: video
There are no comments submitted yet. Do you have an interesting opinion? Then be the first to post a comment.