A measure of the variation in price over time. Also a measure of the risk of a financial instrument.

learn more… | top users | synonyms

4
votes
1answer
132 views

Question about historical volatility ranking

I have seen this strategy example, which uses garch in a regime switching context: https://systematicinvestor.wordpress.com/2012/01/06/trading-using-garch-volatility-forecast/ The author classifies ...
4
votes
2answers
168 views

Time-independent local volatility

Suppose somebody provides us with a surface of European call prices $C(\tau,K)$ where $\tau$ stands for time-to-maturity and $K$ for the strike. By Dupire's results, there is a unique local volatility ...
2
votes
0answers
78 views

How to calibrate volatility surface for Interest Rate Cap&Floor pricing

I'm using Black model to do interest rate Cap & Floor pricing. The volatility is determined by using the bootstrapping methodology. However, afterwards, how should I do the calibration, or ...
0
votes
2answers
105 views

I have portfolio volatility for individual years, can I use them to compute portfolio volatiltiy for subperiods?

Thanks for opening this question. I have constructed some rules for a portfolio with annual rebalancing and am backtesting it for the period 1990-2014. I want to compare the risk-adjusted return to ...
3
votes
2answers
332 views

Is there a way to adjust R PerformanceAnalytics function VaR with EWMA or GARCH method?

Is there a way to upgrade R PerformanceAnalytics function VaR with more risk sensitive approaches like EWMA or GARCH? Or is there another R package which can handle the issue?
3
votes
1answer
131 views

Volatility updating rule using r

I'm trying to program a volatility updating rule using iteration. I start with the well know Heston-Nandi model where the returns dynamics are : with is iid standard normal randome variable, where ...
2
votes
1answer
165 views

On an application of Ito's lemma

Assume that instantaneous returns are generated by the continuous time martingale: $$dp_t = \sigma_t dW_t$$ where $W_t$ denotes a standard Weiner process and One day returns are denoted by $r_{t+1} ...
1
vote
0answers
52 views

Hedge volatility decreases

My particular options positions are typically a long delta, and long vega. Decreases in implied volatility, or specifically the VIX, can drastically alter the profitability of my position. Is there a ...
1
vote
2answers
93 views

Garch for covariance matrix?

I have seen plenty of literature about GARCH on estimation volatility. how about covariance? There are plenty of risk models depending on the covariance matrix. I guess we can assume the correlation ...
2
votes
1answer
447 views

using garch to forecast volatility but getting low persistence model

I am using a GARCH(1, 1) model to try model volatility for a certain stock. I have a GARCH function in matlab that returns the three parameters, omega, alpha & beta. I then use this parameters ...
1
vote
1answer
70 views

Variance Swap volatility

In an article, it is mentioned that a parameter is "the variance swap volatility at time t". I know what a variance swap is but I don't know what they could mean by "variance swap volatility". ...
1
vote
2answers
159 views

How to write a home task report which is part of the interview process for a quant position in a trading firm

I recently appeared in an interview for a quant research post in a trading company. As part of the interview, I was given a home-task to solve in a week. The inerviewer gave me a dataset consisting of ...
1
vote
1answer
164 views

What is an appropriate algorithm to use for tax loss harvesting?

I've been reading into how Betterment and Wealthfront have architected their tax loss harvesting algorithms, but they stop short of providing any real examples. Essentially, they both reduce to: ...
1
vote
0answers
37 views

Reputational Harm

How would you measure the reputational harm incurred on an individual by an organization. How is Market Pricing in the expected payout resulting from the law suit by an individual ? The news breaks ...
19
votes
7answers
30k views

What is the difference between volatility and variance?

How do volatility and variance differ in finance and what do both imply about the movement of an underlying?
2
votes
2answers
77 views

I have portfolio volatility for year 1 and for year 2. What is portfolio volatility for year 1 and 2 combined?

Thanks for looking into this question. Portfolio volatility in year 1 = 15%. Portfolio volatility in year 2 = 20%. What is the portfolio volatility over the timespan year 1 and 2 combined? Is it ...
1
vote
0answers
136 views

How to hedge a long stock with the corresponding volatility ETF

Let us say I want to establish a market neutral position. So if I buy 50 shares of stock (SPY) and I want to delta hedge, I sell an ATM covered call. So that brings the position delta to 0. Now, I ...
1
vote
2answers
426 views

Why is the vega of an at the money option so insensitive to movements in volatility? I.e, why do ATM options have such little Vomma?

I've been trying to understand why at the money options have very little vomma. I was reading and came across a graph that showed vega as volatility changes and I couldn't grasp how the relationships ...
1
vote
1answer
108 views

European vanilla call/put option, when volatility increases, how will gamma changes?

according to the BS formula, $\gamma = \frac{N'(d_1)}{S_0\sigma\sqrt{T}}$, gamma will decrease when volatility increase. How does it intuitively make sense? rather than from the formula.
3
votes
0answers
220 views

Constructing Volatility Smile from American Options

My question is about best practices for reconstructing volatility smiles for a fixed tenor from American option data. For simplicity/liquidity, I am currently considering options on SPY. I am ...
1
vote
1answer
707 views

Bloomberg equity option volatility data

Using the Bloomberg open API, I am trying to program a C++ script that is able to download option volatility data from Bloomberg. I currently do not have access to Bloomberg, but in the coming week I ...
5
votes
1answer
139 views

Which volatility to use to price options on futures contract?

I have some questions regarding pricing futures options and I just want to be sure that my thoughts are correct. I am trying to price options on futures for american & european style. In the ...
6
votes
3answers
2k views

What does it mean to be “long or short in volatility”?

I've heard a question regarding pricing of european calls. The question is: Is the call long or short in volatility when it is (deep) OTM? What is the profile of the implied volatility? I ...
0
votes
1answer
167 views

What are the parameters of the function PORTVAR in Matlab?

According to the Matlab help, Portvar will give the "Variance for portfolio of assets" by entering the returns of the Assets and the corresponding weight. However, it does not explain the parameters ...
0
votes
2answers
135 views

Comparing Portfolio Volatility with Index Volatility seems a wrong method?

thanks for looking into this question. I am comparing an investment strategy against the S&P 500 for a financial article I'm writing. I compute volatility of the Portfolio in this way, as the ...
0
votes
1answer
98 views

I have volatility of a portfolio in year 1 and in year 2. How do I calculate the volatility over the total 2-year period?

thanks for looking into this question. See the picture below (better is right-mousebutton - open in new tab). I also have the price and return data of the Stocks if that's needed to calculate the ...
0
votes
1answer
34 views

Transaction Costs Measure ATOP: What does it mean and exactly measure?

I went through some presentations about LowVol strategies for some indices. In the presentations were tables with average returns, vola, Sharp ratio and ATOP. I have no clue what this ATOP is supposed ...
2
votes
1answer
235 views

Some questions about implied volatilities and how to generate theoretical prices when market prices are not available

I am building a little Excel file that take some option prices in input and plots the volatility smile/surface. I have a script that reads market prices from the option chain for 3 different ...
2
votes
2answers
736 views

How to calculate the volatility matrix with multiple stocks

calculating the volatility for a single stock is straightforward. However, I'm not sure whether my approach for calculating the volatility matrix for multiple stocks is correct: I assume a log-normal ...
9
votes
1answer
451 views

What good papers of short term (<30 seconds) volatility estimation [duplicate]

I am looking for good papers of short term (<30 sec) volatility estimation AND short term volatility forecasting. Do you have something in mind ?
7
votes
5answers
341 views

Can classical economics explain *any* of the so-called stylized facts of finance?

I am doing some reading on the (historical) emergence of the Black-Scholes implied volatility smile for index options (yes - post 87), and I stumbled across an economic paper attempting to explain the ...
1
vote
1answer
171 views

Arrow-Debreu Price in “The Volatility Smile and its implied Tree”

I was reading the old, but still interesting paper "The volatility smile and its implied tree" by Derman and Kani. I have a two questions about the derivation of the $2n+1$ equations, both of them ...
3
votes
1answer
930 views

How to Calculate Confidence Intervals for Moving Averages Given Nonindependence?

I've plotted 30-year moving averages across time for a couple of portfolios, and I was wondering how to calculate a 95% CI for the these moving average data (i.e., across all moving average data ...
2
votes
1answer
425 views

HAR-RV, realized GARCH and HEAVY model for realized volatility

I don't have much experience with volatility modeling using intraday data but I'm in the process of collecting 5mins data. Currently I have ~6 months of data. Is it enough to use these models with ...
6
votes
2answers
290 views

Does it make sense to use upward and downward volatility in option pricing?

Historically stocks have a higher likelihood to increase in price than to fall in price. As such would it make sense to split a stocks volatility measurement into upward and downward components? For ...
0
votes
2answers
96 views

Is the volatility for these two SDEs the same

$$ (1) \ \ d\left(\frac{1}{S_t}\right) =\frac{1}{S_t}\left(\sigma^2-r\right)dt +\frac{1}{S_t}\sigma dW_t $$ and $$ (2) \ \ dS_t = S_t rdt + \sigma S_t dW_t $$ How can you prove that?
1
vote
2answers
187 views

what volatility do we calculate using GARCH model

what volatility do we calculate using GARCH model, Historical vol or Implied vol or Future Vol or Actual vol.
0
votes
1answer
97 views

What math concepts are used in designing volatility models

What topics in statistics and mathematics do I need to understand thoroughly before I can start to dabble with stochastic volatility models and volatility arbitrage?
8
votes
5answers
6k views

What are the advantages/disadvantages of these approaches to deal with volatility surface?

I would like to know if someone could provide a summarized view of the advantages and disadvantages of the approaches on the volatility surface issues, such as: Local vol Stochastic Vol ...
0
votes
1answer
51 views
4
votes
2answers
196 views

Is there a better way to price options than with historical volatility?

I know that annualized historical volatility calculated with closing prices is a much rougher estimate than implied volatility for the correct "volatility" parameter in options pricing models. ...
1
vote
1answer
52 views

Risk-free arbitrage given a volume oracle?

Given a magical oracle who can correctly predict the volume, but not the price, of a given security, does there exist a risk-free arbitrage to capitalize on this information?
0
votes
1answer
46 views

Normal vol - convention

apologies for the simplicity of the question, but I was wondering: what is the quoting convention for normal (bps) volatility? Say I have the following time series of data: Date Close Abs Change ...
0
votes
3answers
116 views

What makes investors risk averse?

There are some regularly-occuring events that coincide with a rise in the implied volatility of an asset. For example, in advance of an firm's annual earnings report, it is typically expensive to buy ...
5
votes
4answers
1k views

How to avoid having negative volatility when applying Heston model?

When applying the Heston model to generate the sample volatility surface, some of the volatility value will be negative. I am just wondering what do practioners normally do with these negative value. ...
1
vote
1answer
98 views

Where can I find a list of market-moving news announcements for different asset classes?

Different asset classes have different important news announcements that move the markets intraday. For instance, oil volatility increases after the EIA Petroleum Status Report, but that announcement ...
0
votes
3answers
513 views

Trading spot volatility

I am reading a paper that very briefly talks about some volatility arbitrage strategies. It's so brief that I do not exactly understand how it works. It says one of the strategy is based on "short ...
3
votes
2answers
146 views

Approximation of different volatilities

Suppose I model the forward swap rate lognormal $$dS_t = \sigma_{ln}S_tdW_t$$ On the other hand we could model it simply by a normal assumption: $$dS_t = \sigma_{n}dW_t$$ I would like to know if ...
2
votes
1answer
680 views

How does Volatility Pairs Trading work?

I've read some material related to pairs trading for equities and I understand the process of finding non-stationary pairs price series that can be cointegrated to form a stationary series. The basic ...
3
votes
2answers
178 views

Cross-sectional volatility vs temporal volatility

Volatility is usually defined as the standard deviation of returns, but sometimes it is calculated as the standard deviation of cross-sectional return divided by the square root of time, where other ...