Questions tagged [sabr]
78
questions
1
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1answer
260 views
Fitting a volatility smile with pySABR -- Python implementation of SABR model
In order to model some volatility smiles I'm using the python's pySABR package.
I ran into a situation when I have two almost identical pieces of code for two different volatility smiles missing the ...
0
votes
1answer
215 views
Can't fit Bloomberg volatility smile with pysabr. What am I doing wrong?
I want to make sure that I can properly use SABR model on 1-period interest rate options, i.e. caplets, therefore I attempted to get lognormal volatilities for 4%, 6%, ATM, 8%, 10% strikes for 3Mx6M ...
0
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0answers
31 views
Should one calibrate SABR model on caps or caplets?
I want to build a volatility surface for caps on a 3M index implied from SABR model. I have a set of cap normal volatilities for a range of strikes (4%, 6%, 8%, 10% and ATM) and maturities (1, 2, 3, 4 ...
0
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0answers
37 views
Does my caplet stripped volatility surface make any sense?
My goal is to build a volatility surface for caps on a 3M index implied from SABR model. I have a set of cap normal volatilities for a range of strikes (4%, 6%, 8%, 10% and ATM) and maturities (1, 2, ...
1
vote
1answer
84 views
How to build a volatility surface for caps from the SABR model?
My end goal is to build a volatility surface for caps. It's well known that SABR model has Hagan approximation formulas for log-normal and normal implied volatilities of options, e.g. caplets, ...
1
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0answers
51 views
How to measure accuracy of SABR volatility surfaces?
I would like to test how accurate are SABR volatility surfaces with respect to historical volatility over a given time period and for a specific equity index.
Reading a few papers I realised that one ...
0
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0answers
61 views
Calculation of SABR delta
I have a relatively simple question on the calculation of the SABR delta. I consider the Bartlett's delta (although my question remains the same for the unadjusted SABR delta from Hagan (2002) ).
The ...
0
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1answer
107 views
Sabr vs Heston for IR swaptions
Why is SABR considered the model of choice for swaptions? Is the Heston model not suitable? Does Heston produce unrealistic dynamics with respect to the swaption market?
1
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0answers
60 views
Adapt SABR Hagan/Obloj model from swaptions to treasuries options
I am a young intern in a brokerage company and I am currently working on developing a new pricer. I would like to encode a skew-visualisation tool and the best way that appeared to me is the SABR ...
1
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1answer
80 views
Cocycle Condition for FX and SABR
I was wondering whether SABR model (or some of its modifications) is actually used by practionarers.
Also, if one models the FX forward with SABR, would the cocycle condition be satisfied? That is, if ...
1
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0answers
54 views
Typical SABR parameter values Equity and FX
Would anyone be so kind to post typical SABR values for equity (e.g. S&P500, maturity 6 months and 1 year) and FX (EURUSD, maturity 6mths and 1 yr) for 'normal' markets and for stressed markets (e....
1
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0answers
42 views
Numerical/integration methods within dynamic SABR
I have a question regarding volatility estimates in the dynamic SABR model. It is well known that the original Hagan et al. (2002) approximation formula for the SABR model does not work good for ...
0
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0answers
96 views
How to interpolate implied swaption volatilities between maturities for SABR?
I want to interpolate the swaption volatility surface (fixed tenor) in the maturity dimension. I have volatility smiles at times T1 and T2, and would like to get the smile at time T with T1<T<T2 ...
4
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0answers
149 views
SABR vs Dupire: when to use what?
I was wondering for which products one would use the (AF)SABR model and for which ones Dupire's Local Volatility model.
If I understand correctly, Dupire is by construction Arbitrage-Free but produces ...
1
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0answers
133 views
Can you use the SABR implied volatility in the Black Scholes formula?
The SABR implied volatility is often used as an input in Black's model to price swaptions, caps, and
other interest rate derivatives.
I'm wondering whether you can use the SABR closed form solution of ...
3
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0answers
96 views
Explicit expression for option prices in SABR?
I am trying to get a grip of the current state of research regarding option pricing in the SABR model.
Am I correct in that, so far, there is no known general formula for the option price in the SABR ...
1
vote
1answer
380 views
Interpreting SABR calibration model output
Calibrate a SABR model?
Following on from this question, I have used the same market data they attached but am unsure on interpreting the output.
When I plot the SABR probabilities against strike for ...
1
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1answer
147 views
Under what measure is the SABR stochastic differential equations
The SABR Model is a CEV (constant elasticity of variance) Cox asset process with correlated lognormal stochastic volatility. A forward rate $F(t,T)$ to time $T$, observed at $t$, and the instantaneous ...
0
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0answers
189 views
How to Calibrate SABR parameters by fixing Beta(Quantlib XL/Python)
Unable to find a good example for either Quantlib XL/Python where we can calibrate Alpha, Rho and Nu by fixing Beta. Any help would be appreciated
1
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1answer
188 views
Is there a ZABR model on Quantlib XL
I am relatively new to QuantlibXL and would like to build a ZABR model in excel. But I cant find much help online. Any help would be appreciated
3
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1answer
1k views
SABR Model Pricing Engine in Python QuantLib
I am looking for a SABR model pricing engine in Python QuantLib setting. I do know that it exists in C++ version, but not sure if available in Python. Any suggestion/feedback with respect to Python ...
2
votes
2answers
391 views
Black Volatility using SABR model
As per the Wikipedia, the SABR model looks like below -
$dF_t = \sigma_t \left(F_t\right)^{\beta} dW_t$
$d \sigma_t = \alpha \sigma_t d Z_t$
I have 3 questions -
...
1
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0answers
65 views
Intuition behind local volatility curve shapes in interest rate environments
I have some questions regarding the intuition behind shapes for the local volatility (LV) curve as seen in quite popular models. Let's say we have the following generalized stochastic-local volatility ...
0
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0answers
119 views
Bond Options Calibration to market volatility using SABR Model
I'm trying to calibrate bond option implied volatility from SABR model to market volatilities, I tried calibration in python but the smile isn't correctly matching with market volatility?
Any help is ...
1
vote
1answer
118 views
Do all stochastic volatility models capture volatility smile?
I started reading SABR model recently.
In Wiki page, it states that the SABR model can capture volatility smile in derivative market.
However, I do not see how it does so.
1
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0answers
70 views
Implied vol expansion for $\lambda$-SABR
Is anyone aware of a good implied volatility expansion formula for $\lambda$-SABR (SABR with mean reversion)?
I am not sure if there is a formula as simple (or just slightly more complex) as the ...
1
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0answers
29 views
SABR - several maturities in equities
SABR model is quite popular and given options on a certain forward, you can easily calibrate it. In Fixed Income, the extensions to several tenors typically involve LMM. Is there a popular way to so ...
1
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0answers
118 views
Hagan et. al original argument for SABR
In the original SABR paper (Hagan et al 2002 ), the introduction of the famous model is motivated by the observation that local volatility models spot dynamics work the wrong way. As the spot ...
2
votes
1answer
199 views
SABR Calibration
I need to generate the Volatility Surface of call options on S&P500 index, my
dataset contains implied volatilities regarding various expiration dates for various strike prices.
My doubt is, ...
3
votes
0answers
151 views
How are Autocallables modelled?
What models are used to price autocallables ? Should we talk about Heston/SABR models which talking about this topic ? Any reference link is welcome.
2
votes
1answer
234 views
Pnl explain using adjusted SABR delta
When looking at SABR, the starting point for a swaption's delta is the usual:
$\Delta = \partial V/\partial F $
However, since we have expressed our volatility $ \sigma $ as a function of our ...
1
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0answers
95 views
How to find the right Shift for the SABR Model
I'm looking for the right approche to find the right Shift for the SABR Model.
4
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0answers
218 views
The error term of Hagan's approximation of Black's vol in SABR
Hagans approximation of Black's implied vol in SABR is very! difficult to understand fully. But I want to ask in here if anyone can tell me more about the error term.
Consider the paper:
http://web....
2
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1answer
1k views
SABR Implied Vol: Normal Approximation vs Log-Normal Approximation
I am having trouble understanding the difference between the normal and log-normal implied volatilities from Hagans SABR model: http://web.math.ku.dk/~rolf/SABR.pdf.
As far as i understand the main ...
1
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0answers
185 views
Black-Scholes vs Blacks model. Which one to use with SABR?
Say I want to compute a call price for a given set of SABR parameters.
I use Hagans approximation and compute $\sigma_B$. The rate is not zero. Should I then compute the option price using
Blacks ...
2
votes
1answer
108 views
$\beta = 1$: Simulation of SABR and whether a solution is *exact*
Quick question regarding the conditional distributions (SABR is just an example here)
Consider
$$dS_t = \sigma_tS_tdW_t$$
$$d\sigma_t = \alpha\sigma_tdV $$
$$dW_tdV_t=\rho dt$$
Hence a SABR process ...
3
votes
2answers
397 views
Does high levels of vol-of-vol parameter in SABR lead to Arbitrage? (Something seems wrong with Hagans formula)
Main question: Do we need to restrict the vol-of-vol parameter in SABR further than $\text{vol-of-vol}>0$ and how do we determine the interval of vol-vol which the model is arbitragefree?
...
3
votes
1answer
289 views
Simulation scheme for SABR beside the standard Euler discretization
QUESTION:
Beside Euler Scheme, is there another more robust (and preferably easy to implement) way to simulate asset path with SABR dynamics?
Simulation that will withstand even for high volatilities....
1
vote
1answer
1k views
Example of complex structured products on FX market?
Lately I have been working a lot with the vol smile and different stochastic volatility models with FX forwards data. Now I want to work with pricing examples through simulations. Can you suggest some ...
0
votes
1answer
367 views
simple SABR model & negative strikes
My goal is to calibrate a simple SABR model.
I do have $tenor$, $expiry$, $forward$ and "market volatilities for strike spread" ranging from -150 to 150 bps.
I think the model can only be ...
4
votes
1answer
2k views
Understanding the ZABR model (an extension of SABR)
http://janroman.dhis.org/finance/SABR/ZABR%20Andreasen.pdf
In this acticle the SABR model is first presented in another form ( see equation 7 in the article ) and then extended to the so called ZABR ...
2
votes
1answer
487 views
zero-shift SABR vega and re-calibration of SABR
I have a zero-shifted SABR model, where I need to confirm if the model is generating the calibration and vega's correctly.
The underlying model is the standard SABR lognormal (there is normal as well)...
2
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0answers
175 views
SABR for swaptions
We calibrate SABR on each expiry and tenor combination using market data. (e.g. 1mx10y, 3mx10y etc.) Then how about the non-standard expiry like 2.5mx10y? Do I linear interpolate the alpha, beta, rou ...
3
votes
1answer
295 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 ...
2
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0answers
113 views
The Free Boundary SABR: Natural Extension to Negative Rates
In the paper by Antonov, Konikov and Spector
An alternative approximation for the SABR model is presented.
I'm interested to implement the formula for the ATM swaptions implied volatilities in the ...
6
votes
1answer
339 views
SABR Question: Why does the market take the beta parameter as a constant?
SABR Question
Why does the market take the $\beta$ parameter as a "constant"?
I see most brokers quoting SABR parameters nowadays.
I've seen many banks use $\beta$=0.5 as a rule.
I've seen quants ...
1
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0answers
483 views
Is SABR being used in practice for Equity options
Just to be clear: By "in practice" I mean what the banks and other financial companies do.
Do financial companies use SABR for pricing equity options?
Consider a stock with price $t$ being: $S_t$. ...
3
votes
1answer
5k views
Calibrate a SABR model?
How do you calibrate a SABR model using R/Python/Matlab?
Using the data example from: https://papers.ssrn.com/sol3/papers.cfm?abstract_id=2725485
1) How does one calibrate the SABR model?
2) How ...
1
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0answers
73 views
Analytical formula for the moments of SABR model?
Do analytical formulae exist for the central moments under the SABR model? Assuming dynamics for the forward rate $\{F_t, t \geq 0\}$ under a shifted SABR model. How do we derive $\mathbb{E}[X(T)^n]$ ...
3
votes
0answers
160 views
SABR: implied vol formulas
I noticed that the approximate implied volatilities in Hagan’s 2002 paper (see B69.a and BC9.c, please refer to the paper for the definition of the parameters):
are different from the formulas on ...