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

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211 views

Intuitive Explanation for Volatility Smile for Equity

I am trying to understand the intuitive reasoning for why volatility is more for deep OTM/ITM put/call then ATM..(why Simles for equity) Why ATM will not have more volatility as deep OTM/ITM option ...
2
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1answer
234 views

Mean reversion time estimation

I am new to mean reversion trading, and I would like to get some good references about how to estimate the time it takes to a mean reverting process to cross its long term mean.
2
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1answer
3k views

What is the equation for Garman-Klass volatility?

I want to calculate realized/historical volatility for the underlying products of various options using the Garman-Klass estimator, but I can't see to find an equation, although I know it involves ...
2
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2answers
953 views

Relationship between European, American options volatility

Suppose, if the price of a European option (say a put) can be shown to be monotone in volatility (say for any maturity), does it follow that American options has to be monotone in volatility? ...
2
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1answer
100 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 ...
2
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1answer
171 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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2answers
3k views

Delta Neutral / Gamma Neutral Positions

I've been trying to find out more about options positions which are both delta neutral and gamma neutral--created with some kind of calendar spread. Supposedly, such a trade will be perfectly hedged ...
2
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1answer
51 views

Integrated volatility

Can someone give me an explanation of what integrated volatility is (and possibly why it is preferred) versus a standard measure of volatility eg variance?
2
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1answer
103 views

GJR-GARCH with $\alpha = 0$ as parameter estimate

I am estimating a GJR-GARCH(1,1) model with variance targeting in R. As data I am using returns on some stock indices. While calculating the GARCH models I obtain $\alpha=0$ for some indices. From ...
2
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1answer
177 views

Effect of volatility on the delta of a call option

In the book 'Dynamic Hedging', Nassim Taleb writes: ...
2
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1answer
260 views

Swaptions vol trading lognormally

What does this mean: "Front-end vols have been trading lognormally while longer tails have traded normally." I read this in a research report, in the context of ...
2
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1answer
410 views

Value at Risk from Delta of a single asset portfolio

I am trying to figure out the following, for me unfamiliar type of question: Given is a single asset portfolio: the Delta of the portfolio is 15, the value of the asset is 10 and the daily volatility ...
2
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3answers
227 views

Why are short expiries associated with more pronounced volatility skews?

I've noticed that for a given strike price, the shorter expiration dates of options have more pronounced volatilities why is that?
2
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1answer
257 views

How to calculate two-time scale variance?

I am having trouble understanding how to calculate two-time scale variance as I do not have a strong mathematical background. Suppose I want to calculate the TSRV at 5 min intervals. Do I calculate ...
2
votes
2answers
971 views

Should I use GARCH volatility or standard deviation in cross-sectional regression?

I want to do a cross-sectional study where the historical, medium-long run volatility of some return series (call it $R_t$) is included as a regressor. Which of the following two estimates of ...
2
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1answer
216 views

How to group mutual funds by volatility?

I want to group Mutual Funds by their volatility. Ideally, I would like to end up with the mutual funds beings attached to different groups: High volatility Medium volatility Low Volatility My ...
2
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4answers
82 views

Do stocks move up and down in value or in proportion to how much they cost?

Do stocks change in value or in proportion to how much they cost? If a stock costs 100 dollar will it generally change value at the same rate as a 700 dollar stock (IE: both will move about 2 dollars ...
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3answers
472 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
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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 ...
2
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2answers
411 views

How to interpret Realized Volatility and TSRV using R

I am looking at some high frequency data and I would like to know how to interpret and compare Realized volatility (RV) and Two Scale Realized Volatility (TSRV). References below. Given X is the log ...
2
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1answer
249 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
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1answer
159 views

Volatility of Futures

Apparently: Under a constant interest rate, the futures price is given by a deterministic time function times the asset price (I think I understand this). This means that the volatility of the ...
2
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1answer
744 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 ...
2
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2answers
185 views

2 stocks, no shorting vs shorting. (concrete questions, mean-variance)

I'd appreciate help with the following questions. Suppose there are two stocks $A$ and $B$ with expected returns $E_A, E_B >0$ and volatilities $v_A, v_B >0$, respectively . Also, suppose ...
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3answers
1k views

How to trade volatility?

I am analyzing the volatility of financial stock returns and let's say I have a pretty good model to forecast tomorrows volatility of the stock returns. So let's say for simplicity reasons I have a ...
2
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2answers
256 views

Time Varying Volatility

If stock returns ($r_t$) are not auto correlated why is that the squared term of the returns (volatility) exhibit serial correlation? Does heteroskedacity, by its nature, imply that time varying ...
2
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1answer
111 views

VEC GARCH (1,1) for 4 time series

I have to estimate a VEC GARCH(1,1) model in R. I already tried rmgarch, fGarch, ccgarch, mgarch, tsDyn. Has somebody estimated a model like that? ...
2
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1answer
66 views

Estimating volatility from high frequency price volume data of multiple stocks

I have price volume data of five stocks, sampled at 1 minute interval for six months. The data is quite noisy, lots of missing data and also some weired spikes. Can someone suggest me how to clean ...
2
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2answers
131 views

Calibrating stochastic volatility model from price history (not option prices)

For stochastic volatility models like Heston, it seems like the standard approach is to calibrate the models from option prices. This seems a bit like a chicken and an egg problem -- wouldn't we ...
2
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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 ...
2
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1answer
337 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 ...
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2answers
444 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 ...
2
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1answer
115 views

How to use calibrated Standard Stochastic Volatility?

I'm considering the standard stochastic volatility model: $$x_t = \rho x_{t-1} + \sigma \epsilon_x$$ $$y_t = \beta \exp\left[ \frac{x_t}{2} \right] \epsilon_y$$ where $y_t$ is the log-returns and $...
2
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2answers
69 views

Measuring Volatility from Execution Prices

I was told of a way of measuring the volatility of a stock by looking at the reported execution prices (from Level III or Level II data.) I'm well aware of how to measure volatility by looking at the ...
2
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1answer
250 views

High frequency price forecast model ARMA GARCH or another?

Can you reccomend model for high frequency data (1 second and less) (returns and volatility forecasting)? Most papers use ARMA, GARCH etc in 1 minute and lower time frame. PROBLEM ARMA does not know ...
2
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1answer
64 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? ...
2
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1answer
509 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 ...
2
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1answer
145 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
80 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 ...
2
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1answer
477 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 ...
2
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2answers
280 views

How to classify stocks by their volatility?

I would like to hear other possible ways of classifying Stocks by the Volatility of their returns. Assuming that I want to characterize each stock as Low, Medium or High Volatility Stock and assuming ...
2
votes
2answers
805 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 ...
2
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1answer
288 views

Square-root-of-time and autocorrelation

My question is that when we have autocorrelation in daily volatilities can we scale daily volatility to annual basis using square-root-of-time rule? Does it breach the main assumption of the rule ...
2
votes
1answer
360 views

How to compare different volatility measures?

I read the Euan Sinclair's book (Volatility trading) in which he suggests different volatility estimators (Close-to-close, Parkinson, Garman-Klass, ...). I am inquiring about what is the best stock ...
2
votes
1answer
121 views

Is the volatility of a trader's wealth equal to the volatility of the underlying assets traded?

Assume that a trader trades in several stocks with different volatilities. The return of the trader's portfolio would be the weighted average of returns and the risk would be a function of the the ...
2
votes
1answer
153 views

evaluation of volatility models using loss functions

This question has two parts, What is the state of the art in an academic or public knowledge sense of volatility forecast model evaluation? Since there are many methods out in the wild, and do ...
2
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1answer
332 views

Which prices to use to compute realized volatility?

For computation of realized volatility, especially range based volatility, deal prices are commonly used. If Level I data available should the deals data still be used or another measures of spot ...
2
votes
3answers
615 views

Logarithmic returns for realized variance?

I am wondering which method makes more sense when computing log returns. I am trying to compute log returns for realized variance, and I have the opening and closing prices for every minute. Since ...
2
votes
1answer
1k views

How to calculate implied volatility and greeks in Bull Put Spread option strategy?

Ok, obviously I am buying lower strike put and selling higher strike put. What is the recommended volatility and greeks to consider in my trade? Volatility: Average volatility between both legs? ...
2
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1answer
205 views

How to enumerate all the possible portfolios with a given target volatility?

Let's say I have $n$ assets and their returns are stored in a matrix $X \in \mathbb{R}^{m \times n}$ (i.e. I have $m$ returns for each of them. The covariance matrix of the returns is $\Sigma \in \...