Questions tagged [stochastic-volatility]
The stochastic-volatility tag has no usage guidance.
367
questions
1
vote
0
answers
50
views
Intuition behind the benefits of Stochastic Local Volatility (SLV) models [duplicate]
There have been various posts on this topic, but they don't really discuss the intuition behind the benefits of the stochastic local volatility (SLV) models over normal stochastic volatility (SV) ...
1
vote
0
answers
63
views
Calibration of $\rho$ in the heston model
When calibrating the Heston model, the gradient of the price of the call/cost function wrt $\rho$ (correlation between $S$ and $V$), is a lot less than the other parameters like $v_0$ and $\bar{v}$. ...
1
vote
0
answers
78
views
Efficient Method of Moments(EMM) for Stochastic volatility model
We are attempting to calibrate the parameters of the Heston model via EMM on historical stock price returns. However, we are first trying a simple stochastic volatility model using EMM.
We have come ...
0
votes
1
answer
21
views
Change of expansion point for singular perturbation solution in Equivalent Black Volatilities
In the paper Equivalent Black Volatilities, an peturbative solution is derived for the equivalent Black volatility of a vanilla call option under the dynamics $dF_t = a(t) A(F_t) dW_t$ by Taylor ...
0
votes
1
answer
114
views
Calibrating the Heston with the Levenberg-Marquardt algorithm
I am trying to implement the Levenberg-Marquardt algorithm similarly to Cui et al. Full and fast calibration of the Heston stochastic volatility model, 2017 here (although using a different method to ...
1
vote
1
answer
89
views
Incomplete market
How to prove that market with one risky asset $S_t$ and interest rate $r = 0$ is incomplete:
$$dS_t = S_t (\mu dt + \sigma_t dW_t^{1}), \quad S_0 = 1,$$
$$\sigma_t = 1 + |W_t^{2}|,$$
$W_t^{1}$ and $...
0
votes
0
answers
49
views
COS method for Wishart Heston Model
NOTE: This code is a piece of code I am using for a master's thesis, so I do not expect someone to do the work for me, but I gladly accept suggestions of any kind.
However, I am trying to get the ...
2
votes
1
answer
106
views
Characteristic Function for Wishart Heston Model
I don't know if this is the right place (at most they will close the post). Anyway, I am trying to implement the characteristic function of the Heston Wishart Stochastic Volatility model illustrated ...
2
votes
1
answer
113
views
Volatility Mismatch in SABR Calibration
Problem Statement
Hi, I am trying to calibrate SABR on a new asset, which is not 'forward swap rate'. While using the vanillaSABR calibration, I find the parameter 'sigma' (one of model parameters, ...
0
votes
0
answers
32
views
how to reflect spot and implied vol relationship in vol curve
There is much evidence about the correlation between spot price and option implied vol in the empirical. This is very important in risk management(i.e. delta hedge). I want to know how to add this ...
2
votes
0
answers
84
views
Volatility Surface Construction: Ask IV, Bid IV and Mid IV
I am presently engaged in a project wherein my objective is to construct a volatility surface utilizing either the SVI parameterization or the SABR model, leveraging real market data. Initially, I ...
3
votes
1
answer
178
views
Vanna Volga Price of an Up and In Put
In the Vanna-Volga approach to pricing first generation exotics, such as single barriers, as I understand it the pricing is as follows:
Let $K,S_t < B$. I'll choose the ATM IV $I_{ATM}$ as the ...
3
votes
0
answers
324
views
Rough Volatility and Change of Measure
When deriving the rough Bergomi model, Bayer et al in "Pricing Under Rough Volatility" (2015) perform a change of measure to ensure the price process is a martingale as shown in the ...
2
votes
1
answer
148
views
Typical values Heston parameters for FX options
I am not as familiar with FX options as I am with equity index options.
For the purposes of numerical testing/experiments I'd appreciate if somebody could tell me what are typical parameter values for ...
2
votes
0
answers
96
views
Is homogeneity preserved under change of measure?
In a paper, Joshi proves that the call (or put) price function is homogeneous of degree 1 if the density of the terminal stock price is a function of $S_T/S_t$. In the paper I think Joshi is silently ...
2
votes
0
answers
59
views
How to replicate a claim in a stochastic volatility model?
Given a Markovian stochastic volatility model with an asset $S$ and a variance process $V$ given by
$$
dS_t = \mu_t S_tdt + \sqrt{V_t}S_tdW_t, \\
dV_t = \alpha(S_t,V_t,t)dt + \eta \beta(S_t,V_t,t)\...
2
votes
1
answer
141
views
Time-shifted power law in path dependent volatility
I can't understand a function which is part of a volatility model.
This is all explained in an open access paper titled "Volatility is (mostly) path-dependent" by Guyon and Lekeufack. My ...
3
votes
0
answers
85
views
Construction of stochastic volatility model from a given local volatility model
The Gyongy's theorem:
Let $X_t$ be a stochastic process satisfying
$$dX_t = \mu_t dt+\sigma_tdW_t$$
where $\mu_t, \sigma_t$ are bounded stochastic
process adapted to the filtration $\mathcal{F}_t$.
...
3
votes
1
answer
95
views
Drift of stochastic variance as slope of the short end of the forward variance curve
I was re-reading Chapter 6 of Stochastic Volatility Modeling by Lorenzo Bergomi. On page 203, he considers a forward variance of the following form:
$$
d\xi_t^T=\lambda_t^T dZ_t^T,
$$
where $Z_t^T$ ...
1
vote
1
answer
107
views
Stochastic volatility estimation in R
Can anyone help me with the stochvol package in R? I estimated the volatilities using this package but I am not being able to understand how to download the ...
0
votes
1
answer
118
views
Smile Dynamics - forward variance
I was reading Smile Dynamics II by Lorenzo Bergomi. It is clear to me that on page 2
$$
V_t^{T_1,T_2}=\frac{(T_2-t)V^{T_2}_{t}-(T_1-t)V^{T_1}_{t}}{T_2-T_1}
$$
is the fair strike of a forward-starting ...
4
votes
1
answer
119
views
Characteristic function of Gamma-OU process
Consider the Gamma-Ornstein-Uhlenbeck process defined in the way Barndorff-Nielsen does, but consider a different long running mean $b$ which may be bigger than zero:
$$dX(t) = \eta(b - X(t))dt + dZ(t)...
0
votes
0
answers
172
views
Barrier options in LSV (local stochastic volatility) / Austing's Smile pricing explained
In his book (chapters 9.5 to 9.7), Peter Austing argues that barrier options are insensitive to the details of the stochastic volatility model used in a LSV model, except for the level of vol of vol. ...
2
votes
0
answers
90
views
Calibration of LSV models to vanna/volga break-even
In this paper, Labordère, the author computes a probabilistic representation of the the vanna/vomma(volga) break-even levels. He mentions that they can be used to calibrate LSV models to historical ...
0
votes
1
answer
49
views
Non-stationarity and repricing as a source of idiosyncratic and systematic "risk"?
1.Assuming a one period economy with two assets in which cash flows are assigned certain probabilities, using the CAPM, we can derive the P0 given the E(CF) at t1. Within this distribution, we have ...
4
votes
2
answers
243
views
Heston Riccati equation
Let
$$
\begin{align*}
dY_{t} &= \left(r - \frac{1}{2} V_{t}\right) dt + \sqrt{V_{t}}dW_{t}\\
dV_{t} &= \kappa(\theta - V_{t}) dt + \rho \sigma \sqrt{V_{t}}dW_{t} + \sigma\sqrt{1-\rho^{2}}\sqrt{...
4
votes
1
answer
254
views
Vega hedge of a barrier option
I was re-reading Lorenzo Bergomi's paper Smile Dynamics I. On the first page, he makes the point that it is necessary for a model to match the vanilla smile observed in markets in order to incorporate ...
1
vote
1
answer
150
views
Can you use a forward rate curve to infer the SABR model parameters?
I am currently doing a thesis on a class of SDE parameter inference methods and using the SABR model as an example for inference. I want to extend the application to market data. My question is does ...
2
votes
1
answer
160
views
Pricing Quantos with Local-Stochastic Volatility model
I would like to price equity quanto options with the Heston Local-Stochastic Volatility model (LSV) but I am having hard time understanding how to apply quanto adjustment in such complex setup.
When ...
0
votes
0
answers
66
views
Trading options - risk adjusted return
I have often wondered what kind of risk restrictions do traders of options in Hedge funds have but have not managed to find any information on this matter. I presume there must be some kind of measure ...
1
vote
1
answer
423
views
How to hedge a dual digital option
Let us assume we have two FX rates: $ 1 EUR = S_t^{(1)} USD$ and $ 1 GBP=S_t^{(2)} USD $. Let $K_1>0, K_2>0$ be strictly positive values and a payoff at some time $ T>0 $ (called maturity) ...
2
votes
0
answers
129
views
Barrier on realized volatility
I am trying to understand the risk exposures of vanilla options that also have a European barrier on realized volatility. For example, the option could knock out if the realized volatility over the ...
7
votes
3
answers
1k
views
Is variance swap long volatility of volatility?
In JPM's note on variance swaps, on page 29, they say "... a long variance swap is also long volatility of volatility".
In Bennett's book Trading Volatility, on page 115, he says "... a ...
0
votes
0
answers
72
views
Affine Jump Diffusion
I'm currently looking into affine jump-diffusions. I would like to get to know the literature better and I know the paper by Duffie, Pan, and Singleton (2000) is a very celebrated paper. Although I ...
0
votes
0
answers
66
views
Heston Process: Accept-Reject Sampling to Alleviate the Problem of Negative Variances
I've read even in recent papers, and on page 21 of the book "The Volatility Surface" by Jim Gatheral (2006), all the debate over whether to reflect or truncate negative variances whilst ...
0
votes
0
answers
90
views
Hurdle Barrier option
Let us denote the upper and lower barrier levels by $B$ and $b$, respectively. The payoff of the knock-out hurdle double knock-in barrier call option can be defined as follows:
$$\left(S_T-K\right)^+\...
1
vote
0
answers
108
views
Stochastic volatility with jumps [closed]
I'm reading the Duffie, Pan, and Singleton (2000) paper now and I've stumbled upon something that seems to me as an inconsistency. Whenever I look up the SVJJ model, I see that its log-transform is ...
0
votes
1
answer
162
views
How calculate expectation and variation of stochastic integral Based on Heston model?
I was calculated Heston volatility model. But I think it is wrong.
$dS_t = \mu dt + \sqrt V_t dW_t^s$
$dV_t = k(\theta - V_t)dt + \sigma \sqrt V_t dW_t^v$.
$dW^s_t dW^v_t = \rho dt$
take integral to ...
0
votes
0
answers
35
views
Surface SVI and value-at-risk computation [duplicate]
Currently interested in some Value-at-risk calculation methods, I understood in a video by Claude Martini (https://youtu.be/_OZvk-G92EQ), that it is now common to see SSVI-based VaR calculation models ...
3
votes
2
answers
1k
views
SABR model - beta
In the SABR model, the parameter beta largely controls the back-bond behaviour of the model. How do people estimate beta?
One approach is to regress atm vol vs forward, i.e.
$$\ln(\textrm{atm vol}) = \...
1
vote
0
answers
104
views
Why is the market price of risk a non-entity according to Bergomi?
I am reading Bergomi's book Stochastic Volatility Modelling. In the chapter 6 dedicated to the Heston model, page 202, he describes the traditional approach to first generation stochastic volatility ...
2
votes
1
answer
179
views
Strange use of dynamical programming principe
I am in a finance seminar and yesterday evening we had a lecture from a quant in a big bank about shortcomings of Heston model.
He was deriving the Heston PDE. (I know how to derive the Heston PDE ...
1
vote
0
answers
363
views
Implied volatility to local volatility via Dupire
I am doing some self study on stochastic local volatility modelling and am having a hard time replicating some results from the paper "FX Option Pricing with Stochastic-Local Volatility Model&...
1
vote
1
answer
113
views
Impact of stochastic rates on varswaps and volswaps
Let us consider that we are looking at issuing some varswaps or volswaps on some FX rate. By longer term I mean something longer than 3 months. Different from this time two years ago, now the interest ...
2
votes
1
answer
191
views
Initial forward variance curve calibration
Let $V_t^{T_1, T_2}$ be the forward variance swap rate for the period $[T_1, T_2]$, seen from $t$ (see for instance Lorenzo Bergomi's Smile Dynamics II) and let $\xi_t^T = V_t^{T,T} = \frac{\partial}{\...
1
vote
0
answers
69
views
Mixing formula for SVJ models
I am trying to understand the mixing formula (Hull and White formula) for stochastic volatility models with jumps in the asset price. One article which discusses this is Lewis, The mixing approach to ...
3
votes
0
answers
152
views
Useful methods to avoid degenerate calibration? (Heston model in my case)
I have implemented a Levenberg-Marquardt(LM) based method to calibrate the Heston model against market data by minimizing a weighted $L^2$-norm of differences of market vs model prices. Pretty ...
0
votes
0
answers
48
views
Reference request: Approximate mapping of a multi-factor stochastic volatility model to single-factor stochastic volatility model
I am looking for approaches to transform a more complicated stochastic volatility model such as the one shown in Section 2.2 of Smile Dynamics II to a single-factor model such as the one shown in ...
0
votes
0
answers
623
views
Mid-curve swaption pricing - how to get the spread vol?
I believe I understand the following (from the accepted answer to the Quantitative Finance question called "volatility of a mid curve option"):
A swaption in which the underlying swap ...
2
votes
0
answers
206
views
Implied volatility skew decay over expiry
I seem to remember the implied volatility skew of European options decreases as the expiry increases. It is true for the Heston model under some approximation. What are the good references that prove ...