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

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57 views

Solving a Non-Linear PDE using a Finite Difference Scheme

I have the following non-linear PDE and I have no idea how to go about solving it using a finite difference scheme in Python. Can someone get me started and/or point me to an algorithm for doing this? ...
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59 views

variance ratio for pair-trading

I am using the variance ratio test to check whether my sequence is mean reverting in that test there is a parameter n, How in general I choose this n? or what is the meaning of this parameter? ...
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0answers
46 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 ...
2
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1answer
144 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} ...
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41 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 ...
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2answers
70 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 ...
3
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0answers
65 views

DCC GARCH - Specificating of ARCH and GARCH parameter Matrices STATA

The command in STATA to calculate the DCC model of two variables is: mgarch dcc ( x1 x2=, noconstant) , arch(1) garch(1) distribution(t) $$ \begin{bmatrix} ...
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1answer
58 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". ...
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1answer
262 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 ...
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2answers
144 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 ...
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44 views

SRRI calculation for absolute return funds

I am trying to understand the formula for calculating SRRI for absolute return funds described in ESMA's guideline CESR/10-673, and Richard's answer has been of great help (What does this formula (to ...
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1answer
111 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: ...
3
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1answer
248 views

How to calculate implied volatility smile of basket using correlations?

For a basket, the realized volatility can be calculated using: $$\sqrt{\sigma_1^2 + \sigma_2^2 + 2 \sigma_1 \sigma_2 \rho}$$ If I have the volatility surface of two underlyings S1,S2 (strike space). ...
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36 views

Correction factors for volatilities of smoothed returns

In An Introduction to High Frequency Finance (http://www.amazon.ca/Introduction-High-Frequency-Finance-Ramazan-Gen%C3%A7ay/dp/0122796713), the authors (on page 253) build a tick-frequency volatility ...
3
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1answer
104 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 ...
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1answer
1k views

Correctly applying GARCH in Python

Problem: Correct usage of GARCH(1,1) Aim of research: Forecasting volatility/variance. Tools used: Python Instrument: SPX (specifically adjusted close prices) Reference material: On Estimation of ...
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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 ...
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3answers
254 views

Variance swap replication and variance vega

Noob here. I've been trying to gain a better understanding of variance swaps and what better way than to replicate it with a portfolio of better understood instruments. I have read the GS 1999 ...
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0answers
104 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 ...
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81 views

How to calculate probability of option expiring in the money?

Given the following values ...
3
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1answer
115 views

How to get around flat likelihood function when calibrating GBM parameters

(Hope this is the correct place for this question - I posted it first on stackoverflow:) I want to calibrate jointly the drift mu and volatility sigma of a geometric brownian motion, ...
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1answer
73 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.
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135 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 ...
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1answer
218 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 ...
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0answers
76 views

Volatility Surface Constituents, do's and dont's

Recently I have been working a lot with implied volatility and volatility surfaces. The basic idea is easy to follow: 1) Gather market prices of options at different (Strike,Expiry) 2) Calculate ...
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2answers
187 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 ...
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1answer
102 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 ...
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2answers
129 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 ...
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3answers
694 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 ...
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1answer
97 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 ...
2
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1answer
116 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 ...
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2answers
53 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 ...
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1answer
90 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 ...
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2answers
65 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 ...
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92 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 ...
0
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1answer
30 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
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1answer
177 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 ...
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0answers
59 views

How do I track implied volatility of specific delta?

I'm a newbie with respects to volatility trading and options. I recently purchased a book on the topic called "Trading Implied Volatility -An introduction" by Simon Gleadall. It's been one of the most ...
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1answer
131 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 ...
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329 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 ...
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2answers
203 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 ...
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154 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.
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95 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?
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1answer
86 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?
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36 views

volatility grouping

I was working on risk levels of a combined portolfio (includes options,futures as well as stock). While using greeks we can asses some value of a portolio, but when one needs to assess some kind of ...
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1answer
51 views

Is the price of a binary call not monotonous with vol for OTM

Is this true and how would you prove it
3
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2answers
157 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. ...
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1answer
47 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?
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82 views

Vanna-Volga method to infer vol surface with just few realtime tick data

My broker gives me the opportunity to get realtime tick data for up to 50 fields. Since I would like to monitor option chains, this amount of data is very limited. Suppose I am interested in ...
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1answer
36 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 ...