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

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1k views

how do we know if the volatility which is quoted in market is Normal (Bachelier model) or log normal (Black 76)?

in market, many instruments are quoted in volatility, but how we can tell what kind of volatility is this? is it normal volatility, or lognormal volatility. because it affect our hedging positions so ...
10
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3answers
396 views

Historical Volatility vs Implied Volatility Performance in Pricing Options

I consistently read on academic papers, when pricing options, using implied volatility is better than using historical volatility. Because, market is more "forward-looking" and historical data is "...
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1answer
52 views

impact model what volatility to use

I am looking at the market impact paper here (http://www.cims.nyu.edu/~almgren/papers/costestim.pdf) and I had a question about volatility on page 11. On page 11 it is stated: "For volatility, we use ...
3
votes
3answers
246 views

Could we estimate a portfolio's volatility using a GARCH on the portfolio returns?

Estimating the volatility of a portfolio is typically done by first estimating the covariance matrix. This, however, can be difficult to do accurately and predictivly. This paper gives a nice summary ...
2
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0answers
101 views

Callable bond price sensitivity to Hull-White volatility changes

I'm using classic Hull-White model for short term interest rate dynamic: $$dr(t)=[\theta(t)-\alpha(t)r(t)]dt+\sigma(t)dW(t)$$ (Notation is quite intuitive, anyway I am using the same as Wikipedia ...
2
votes
3answers
510 views

How to predict daily range of forex?

I am trying to predict the intraday moving range of stock/forex (essentially, high-low). Here are some ideas based on what I've been reading recently (do not have quant background, so basic level of ...
2
votes
2answers
77 views

Volatility of Multiple Stocks

According to BSM, Stock Price follows log-normal distribution s.t. $$S(t)=S(0)*\exp(\sigma\sqrt t Z-(\sigma^2t)/2)$$ where Z is standard normal variable Then volatility of this stock is $\sigma \sqrt ...
7
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2answers
638 views

Why linear interpolation not appropriate for volatility surface construction?

We know linear interpolation is not appropriate for constructing a surface, but why? In the book, "Foreign Exchange Option Pricing: A Practitioners Guide", the author writes: native linear ...
4
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2answers
129 views

Estimating an appropriate haircut for illiquid stocks

I am trying to determine an appropriate haircut for a basket of illiquid stocks that barely traded during the year. Can someone suggest me an approach to estimate the risk? My dataset has a lot of ...
5
votes
2answers
397 views

How to calculate volatility on intraday data?

I have several weeks of minute-by-minute stock data (start and end prices, volume). Everything I've read so far leads me to believe there isn't a standard method for volatility, which is leaving me ...
6
votes
1answer
244 views

Density forecast of a GARCH model

I am currently working on developing a series of density forecasts and I am encountering some problems. I am working on weekly S&P 500 returns and the returns process is described as $r_{t} = \...
3
votes
2answers
162 views

How to user GARCH(p,q) to identify most volatile sector?

I would like to ask help concerning the utilization of GARCH(p,q) models to identify volatility. Suppose that I have daily closing prices of 6 financial sectors spanning several years, and I am ...
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1answer
629 views

Calculate and plot historical volatility with Python

I have downloaded historical data for FTSE from 1984 to now. What I would like to do is to graph volatility as a function of time. What I have written is: ...
7
votes
2answers
316 views

HFT to blame for Flash Crashes?

Some people 1, 2, 3 claim that High Frequency Trading is partly to blame for the extreme volatilities in the markets yesterday (24. August 2015). Is that true? Is the amount HFTs move even enough ...
0
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2answers
157 views

How to handle currency change in exchange rate volatility measurement

I am trying to measure exchange rate volatility in some countries and I am using their currencies against euro. Problem is that one of them is Slovakia which has changed the currency in 2009 from ...
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0answers
105 views

GARCH filtering and extreme value theory

We are evaluating a model for risk management based on extreme value theory using peaks over threshold and markov chain monte carlo methods. In doing this, we are firstly fitting a GARCH (we have ...
2
votes
1answer
71 views

How to measure the volatility of illiquid bond with no historical prices

The basket of corporate bonds that I am following barely traded after the issuance. Hence, there is no historical data to estimate the volatility. Can you suggest me a different approach to come up ...
6
votes
2answers
573 views

How to calibrate a volatility surface using SVI

I've read the following paper by Gatheral and Jacquier and have several question regarding the calibration of a volatility surface in a arbitrage free way and some theoretical aspects. Let me first ...
2
votes
1answer
353 views

2-step estimation of DCC GARCH model in Python

Embedded in this thread are multiple questions. I'm currently im the process of implementing a DCC GARCH forecast model on quantopian (a python-powered trading platform). The two step consists of ...
2
votes
2answers
449 views

Ideas about Stochastic volatility models

I am currently working on comparing different models for modelling the volatility and then pricing vanilla options (I use option prices on real stocks in order to calibrate my models and then I ...
1
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0answers
94 views

GARCH estimation does not work, error in my returns?

Hey everyone and I hope that there are some smarter people out here that can help me out with my problem...: I have trouble with my implementation of a GARCH(1,1) model and I do not know how to move ...
0
votes
1answer
487 views

Realized Volatility vs. Standard deviation of log returns

I am interested in calculating high frequency 5-minute intraday volatility. I am going to use the standard Realized volatility which is the square root of the sum of squared log returns. Given X is ...
5
votes
1answer
396 views

Is volatility for the next day forecastable? To any extent?

In a more general way: is there 1) a methodological approach to quantify the correctness of a model that produces a probability distribution for the, say, S&P 500 index return for the next ...
6
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1answer
230 views

How is implied volatility derived?

How to compute Implied Volatility Calculation? The above link shows that there multiple ways to calculate implied volatility. My question is that for most of the common data sources like Bloomberg, ...
4
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1answer
218 views

Calculating 6-minute, 20-minute, 45-minute, and 3-hour volatility

I am looking to measure the volatility from the open of the market until a trade takes place and use that volatility in post-trade regressions to help explain transaction costs. A simple regression ...
0
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1answer
71 views

Interpreting and scaling of Realized Variance with sample data

I have some question about realized variance(RV) and I have some sample prices below to work with. You can run the R code below to build a vector of log returns. Three are 78 5-minute buckets in a ...
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0answers
51 views

Estimate volatility in forecast

I have a model with a rolling forecast. In each time step $t$, I predict the price for the next periods, e.g. $\hat{p}(t, t+1)$ and $\hat{p}(t, t+2)$. If I start in $t=0$ and arrive at $t=2$, I ...
2
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1answer
101 views

Garch models and assumption of stationarity ?

I found big inconsistency in the GARCH models and their underlying assumption of stationarity. GARCH models require that data must be stationary, where stationary means both mean and variance are ...