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Questions tagged [volatility]

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

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Inherent volatility of selling longterm options and buying short term options

A two-month option has an implied vol of 60%, the corresponding 2-year option has an implied vol of 34%. You buy the short terms and sell the long terms. What is the inherent volatility of the total ...
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30 views

How closely do option prices correspond to black scholes [on hold]

Just wondering how closely real option prices correspond to black scholes. Any non quantitative answer is useless.
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135 views

What does Volatility Smile tell? [on hold]

Could you please share your opinions about Volatility Smile? What does it tell us when it gets more convex or when its level changes over time or any other change on it. Any paper/work/blog ...
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45 views

Break-even volatility for delta hedge portfolio

After simulating practical and theoretical PnL of a delta hedged portfolio on some data from the SPX500 under 0.15 management Vol I want to find the Vol which gives me an accumulated PnL of 0. ...
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38 views

Multivariate Markov Regime switching GARCH

I have a regression with 4 independent variables and a dependent variable. I want to implement a Regime switching GARCH model but have been unable to find a package in R,Python or Matlab. MSGARCH ...
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52 views

What is 'conditional variance' in a GARCH model?

How can a single observation possess variance (by definition it is 0)? For example, we read notation such as sigma(t) as the conditional variance at time t? Yet GARCH's generate conditional variances ...
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31 views

Negative theta in Log-linear stochastic volatility model

I was asked to simulate the following geometric Brownian motion to get paths for the SPX stock price. the process follows a Log-Linear stochastic volatility. $dS_t = \mu S_tdt+e^VS_tdW_1 $ where ...
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55 views

Are extended SABR models useful for options with non-negative underlying

https://papers.ssrn.com/sol3/papers.cfm?abstract_id=2731359 http://janroman.dhis.org/finance/SABR/ZABR%20Andreasen.pdf In the two articles listed above we see several ways to extend the original ...
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132 views

Derivation of VIX Formula

I've read a lot of derivations about VIX formula. I can say it is -adjusted- fair strike of variance swap. But I can't see how it goes from variance swap rate to VIX formula. In particular I can't see ...
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72 views

Option value with different spot prices [closed]

I found this post online which is plotting different results for option value and greeks depending on spot price. Why would someone want to do calculate the value of the option with different spot ...
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66 views

Mixed local-stochastic volatility model in Quantlib

At a conference the speaker mentioned that it is a standard approach today to use a mix of local and stochastic volatility model in equity, FX and interest rates. Can you please suggest the most ...
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73 views

Finding Lead-Lag Relationship [duplicate]

Given two series of data, volatility and returns, is there a way (Excel) of finding which one is the leading factor and lagging factor? Thank you for your help.
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39 views

Threshold to consider the daily change of a bond price unusual?

In the context of compliance and market abuse monitoring, what relative change threshold would you choose to decide if transactions should be looked into? For example, if a bond price had a relative ...
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353 views

Variance swap volatility - ATMF vol, Skew and Curvature

In a pure diffusion setting, it is a well known result that the volatility $\sigma_T$ of a fresh-start variance swap of maturity $T$ as seen of $t=0$ verifies \begin{align} \sigma_T^2 &= \Bbb{E}_0^...
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35 views

What are the different indicators to measure historical volatility for stocks on individual basis?

Google search shows there are three indicators to measure volatility: 1. Average True Range 2. Standard Deviation / Variance 3. Bollinger Bands. What are the indicator(s) that you use to identify ...
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67 views

Whats the big deal between volatility and the risk free rate?

I am trying to understand asset price volatility. Many of the news articles I read link how stock market volatility is linked to asset price volatility? To give an example, in Mike Mackenzie's (...
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79 views

How to determine the risk-neutral measure in a Heston model?

To clarify, I'm quite familiar with the risk-neutral pricing framework, and I know one can efficiently Monte-Carlo a Heston model via the non-central $\chi^2$ distribution approach. But so far we're ...
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32 views

Volatiliy in a at-the-time call option [duplicate]

I understand that the vega of the Black-Scholes equation is a positive function, which means the value of the option is an INCREASING function of the volatility, since vega is the derivative of the ...
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Does your Parkinson volatility ratio work as Taleb explained?

According to Dynamic Hedging: Managing Vanilla and Exotic Options (Taleb, 1997), the Parkison volatility estimator has several meaningful properties. It is defined $$P=\sqrt{\frac{1}{n}\sum_{i=1}^{n}\...
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194 views

Vanilla Option Prices from Local Vol Surface (using neither MC nor PDE)

There are numerous papers that describe the derivation of the Local-Vol equation using available market prices of options. For example: Dupire's formula (see e.g. OpenGamma (2013)) gives us LV in ...
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52 views

Rolling forecast using GARCH model

EDIT This is not a duplicate of my original question linked, since I have since overcome that problem and have posted an answer. Since solving the previous problem, I have run into the problem ...
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Intuitive description of the Spillover Index by Diebold and Yilmaz

I am struggling to grasp the steps outlined in the 2009 paper by Diebold & Yilmaz, which introduces the framework for a spillover index. The final expression for a spillover index for a two ...
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Estimating an GARCH(1,1) model? Long hand method

I am really trying to invest some time to estimate a GARCH(1,1) method, I know there is many statistical packages that will do this for me (Eviews, MATLAB, R), but I am trying to do this by hand, so ...
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87 views

Is this the correct way to forecast stock price volatility using GARCH

I am attempting to make a forecast of a stock's volatility some time into the future (say 90 days). It seems that GARCH is a traditionally used model for this. I have implemented this below using ...
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2answers
63 views

Difference between volatility measures of a basket of assets

I am trying to understand intuitively the difference between two different measures of realized variance of a basket of assets. The first measure I am aware of is when you take the realized variance ...
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58 views

In search of nice (approx) function forms of the volatility of cumulative simple returns

Let's consider a period $t\in[0,T]$, and let the simple return over year $t$ ($1\le t\le T$) be $r_t$. Assume $r_t$ are iid normal. The cumualative simple return over the whole period $[0,T]$ is $$R_T=...
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181 views

How is volatility different from variance?

I always thought volatility was just variance ^ (1/2). Now I'm reading this book and it's saying that the two are different concepts. Excerpts include: Partly due to its use in Black-Scholes, ...
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91 views

Good references on Heston Model?

I am looking for good bibliographic references on Heston Model and Stochastic volatility models in general. Does anyone know any good introductory/intermediate references on this topic?
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66 views

How rapidly should estimated volatility and volume change for estimating market impact in small markets?

The cost of market impact is usually modeled as: $$ \Delta{P} = \delta \sigma (\frac{Q}{V})^{1/2} $$ Where: $ \Delta{P} $ is the change in price of the asset caused by the transaction size $Q$ $\...
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93 views

Poor results forecasting stock price volatility using Python's GARCH model

As far as I understand, forecasting stock price volatility should be more achievable than forecasting absolute prices or returns. It seems as though GARCH models are the traditional and most widely ...
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28 views

How to reasonably aggregate returns across both different assets and different time-horizons?

This might be a somewhat open question, so any suggestion of improvement is welcome. Suppose at time $t=0$, we have $N$ different assets whose weights are $w_1,\cdots,w_n$ ($\sum w_i = 1$), and they ...
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117 views

Splitting theta from vol carry

What is the best way to splitting theta and vol carry on say a long calendar trade? Basically trying to split the "good" carry component of a trade from the "bad" carry (theta) which could be earned ...
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How to calculate number of round trips given volatility?

Suppose we know stock price volatility is normally distributed with mean = 0 and annual volatility say 20%. Let's assume markets never close and we can trade at 1 second intervals. Let's assume stock ...
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VXX Put pricing

Last week at Friday's close, the Dec 14 37.5 Put options were selling for \$.68 with VXX at \$40.29. This week at Friday's close, the Dec 21 37.5 Put options were selling for \$.38 with VXX at \$40.50....
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What is the use of undiscounted Futures/Option Prices

Reading the great book of Gatheral on Vol Surfaces (link) I can't help but notice that throughout he uses undiscounted option prices (though he obviously never assumed rates to be zero). See e.g. ...
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248 views

arbitrage free volatility surface

Why is calendar spread arbitrage equivalent to $\partial_t \omega(k,t) \geq 0, \forall k \in \Bbb{R}$ where $\omega(k,t) = \sigma^2(k,t) t$ and $\sigma(k,t)$ represents the Black-Scholes implied ...
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implementing Volatility Managed Portfolios

How to I calculate the value of c in the vol-managed equation specified by Moreira & Muir Volatilty Managed Portfolios (2016) Equation 1? Portfolio return in month t+1 =$$\frac{c}{RV_t^2}f_{t+1}$$...
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What is, here, the relationship between “compound” and “arithmetic return” and “volatility”?

I'm trying to find the exact (ie, not an approximate) relation between the "Compound Return", "Arithmetic Return", and the "Annualised Volatility" as given the assumptions below, and from there the ...
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Variance Swap : dividends and rates

In a simplified world you can assume that the var swap is replicated by a continuous set of calls and puts and interest rates are equal to zero. So your PNL is only sensitive to the volatility. But in ...
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170 views

Fractionally Integrated GARCH

I am currently working on a project to compare different GARCH(1,1) models on a financial data set. I use the rugarch package in R, and everthing seemed fine at first. However, now that I have started ...
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1answer
60 views

Relationship between asset volatility and debt and equity value

So how I understand it, higher asset volatility implies a higher call option price. The Merton Model holds that the value of equity is a call option. This therefore implies that the equity value must ...
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1answer
115 views

Options on realized volatility / variance

If I'd like to price options on variance/volatility in the Heston model. Is MC simulation and/or finite difference the only way to do it? Or is there an analytical expression for the probability ...
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1answer
225 views

Realized volatility forecast vs Implied volatility

I have forecasts of realized volatility, as well as implied volatility for individual traded options of the S&P500. I want to simulate a simple trading strategy; that is, buy signal=1 if ...
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175 views

Barra covariance matrix construction

I am trying to replicate the covariance matrix used by Barra risk models. All Barra models have half life parameters for volatilities and correlations (e.g. if the half life for volatlity is 90 days, ...
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1answer
141 views

Variance-Covariance VaR: how to get the volatility?

Because the variance-covariance VaR assumes that the returns are normally distributed, in theory it is easy to get VaR by simply finding the mean and the volatility (standard deviation) of the ...
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60 views

Estimating daily volatility of unevenly/irregularly spaced time series data

Say I have time-series data that is unevenly spaced, with anything between 4-50 hours of spacing in between. The data comes from a trading account history, which has captured the balance of the ...
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41 views

target correlation for portfolio

Given a long / short equity portfolio, I want to have some net long exposure. My portfolio volatility is fixed to a target, so in trying to have a certain beta to the market, the only thing I can ...
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102 views

Volatility Index for Industries

The VIX index is based on the S&P, I am wondering the feasibility of creating a VIX index for each of the S&P 500 Industries? Would this even be possible?
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111 views

How accurate are Black-Scholes estimates of Vega, Volga, Vanna

Wikipedia provides analytical formulas for calculating Greeks. I can get Delta, Gamma, Theta all from Bloomberg. I need Vega, Volga, Vanna for my research. Should I use these analytical formulas for ...
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118 views

Volatility clustering and Behavioral Finance, possible explanation

Currently studying about time series modelling of financial data and faced the known GARCH$(p,q)$ model for modelling volatility. We observe that big changes are followed by large changes and vice ...