A contract that gives the owner the right, but not the obligation, to buy or sell a security at a fixed price in the future.

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Basic question about Black Scholes derivation

In the derivation of the Black Scholes equation, the value of the portfolio at time $t$ is given by $$P_t = -D_t + \frac{{\partial D_t}}{{\partial S_t}}S_t $$ where $P_t$ is the value of the ...
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2answers
162 views

Do Bond Put Dates always fall on Coupon Dates (for non-zero coupon bonds). Calculation rules for Coupon Dates

This may not be the most appropriate SE site to ask this question, but I can't seem to find a better place to ask, so here goes: Do Puttable Bonds' put dates always fall on Coupon Dates? When they ...
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1answer
244 views

Eurodollar Options Stike Price > 100 bps

Looking at Eurodollar IR options market data coming down from CME, I can see a whole host of options where the strike is > 100 bps. My understanding in this case is that puts will always be in the ...
3
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1answer
300 views

Which approach is better for modeling option exercise strategies, rational or behavioral?

This question is most relevant to the evaluation of embedded options, such as the refinancing option granted to borrowers in the mortgage and bank loan markets, or the call option present in some ...
3
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1answer
140 views

Monte Carlo and PDE results are different for a Call Option!

Okay so this might be a fairly trivial question but I'm having an issue with valuing a call option using both a Monte Carlo method and a PDE method. When I started I first used the parameters: Spot =...
3
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1answer
233 views

Find call and put volatilities using ATM, Risk reversal and Butterflies volatilities

I have to plot the implied volatility surface for EUR/USD. So, my goal is to produce something like that, from put delta 10 to call delta 10: Searching for informations, I found that I could find ...
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4answers
161 views

Black-Scholes formula proof, without stochastic integration

I've looked into many books at my academic library, and very often it goes like this: Brownian motion Then, stochastic integration (Itô's formula etc.) Application: Black-Scholes formula for price ...
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1answer
88 views

How to get Correlation using Options data?

I can calculate the "Implied Beta" using implied volatility for the option stock, and implied volatility for the market (VIX). Is there any way to calculate also the correlation without performing a ...
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1answer
123 views

What is the correlation between these two functions of GBMs?

Let's say that I have two correlated GBMs: $$dA_t = A_t \sigma^A dW^A_t$$ $$dR_t = R_t \sigma^R dW^R_t$$ $$dW^R_t dW^A_t = \rho dt$$ I am trying to price a derivative which payoff at time $T$ is: $$...
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2answers
108 views

Hedging portfolio and extraction PDE of SV model with stochastic interest rate

How can I extraction this PDE \begin{align*} 0 =& P_t+P_SS(r-\delta)+P_\sigma a(\sigma)+P_r\alpha (r,t) \\ +& \frac{1}{2}P_{SS}S^2\sigma ^2 + \frac{1}{2}P_{\sigma \sigma}b^2(\sigma)+\frac{...
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1answer
124 views

Why must a replicating portfolio be self-financing?

If I have a trading strategy such that at each time $t$ I own $\Delta_t$ units of stock $S_t$ and $\psi_t$ units of bond $B_t$, it is a replicating strategy for some claim with time $T \geq t$ payoff $...
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2answers
148 views

What is the use of options pricing formulas

This may seem like a dumb question, but if the EMH is generally true, wouldn't options already be correctly priced? Why do we need all these intricate formulas, unless we think the prices are wrong or ...
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1answer
165 views

Different Exercise Style Options on Same Underlying

Some equities on European markets have options traded in two different exercise styles: American and European. Examples: ABB and ABB (european) on Eurex Banco Santander on MEFF Consider ...
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1answer
350 views

how to define liquidity in equity, index, and etf options

i've heard several ways to put a metric on liquidity of options.. obviously liquidity isn't a constant.. things like the Bid/Asks spread, liquidity of the underlying.. Trying to find a way to ...
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1answer
582 views

Choice of epsilon for numerical calculation of vega in binomial option pricing model

I have a binomial option-pricing model (I don't think the details of how its implemented are relevant). However, when I go to calculate vega, I am essentially running the model a second time with new ...
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1answer
456 views

Value options when the currency’s risk free rate is negative?

How would you handle a negative interest rate in index/equity options valuation? An example would be negative rates for short term maturities for Swiss Frank (CHF).
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2answers
1k views

How to calculate COMPOSITE underlying implied volatility from ATM (near month) option prices?

I am trying to calculate the implied volatility of an underlying given observed prices of call and puts. There are two scenarios: The ATM strike is pinned by the market (i.e. underlying level == ...
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1answer
121 views

VAR of portfolio containing options, equities and forwards

If we want to calculate VAR of a portfolio using variance covariance matrix (delta normal method), containing equities, forwards and options, how do we treat each asset class for making the variance ...
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4answers
215 views

Model Price vs Market Price in terms of Fair Price (Options)

Before I start: Ok, this is something I investigated for a fair amount of time and my question is semi-academic. To simplify, I will introduce the short bit (TLDR) of my question and then lay out ...
3
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2answers
159 views

American vs European Options on equity index options

I have a question regarding the usage of European vs American Options. According to Professional Risk Mgr Handbook 2010, American-style options are used mostly on equities whereas European-style ...
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1answer
245 views

Numerical example of how to calculate local vol surface from IV surface

I'm looking for an excel example (not a copy of Dupire's eqn) of how to convert an IV surface to a local vol surface. If unsuccessful I'll work through Dupire's eqn but would be helpful to look at an ...
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1answer
114 views

Boundary conditions of PDE from SV model with stochastic interest rate

The PDE for the American put option price $P(S,\sigma ,r,t)$ is \begin{align*} 0 =& P_t+P_SS(r-\delta)+P_\sigma a(\sigma)+P_r\alpha (r,t) \\ +& \frac{1}{2}P_{SS}S^2\sigma ^2 + \frac{1}{2}...
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1answer
150 views

Distribution of Black Scholes call option price at time 0<t <T

Does anyone know how to find the probability law (distribution) under P* of a Black Scholes Call Option price $C_t$ for $0 < t < T $? (Under P*, $ dC_t = \frac{\partial c}{\partial s}\sigma S_t ...
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1answer
89 views

Binary option expression

Given r=0, σ(K)=const Binary=lim┬(ε→0)⁡〖((C(K,σ(K))-C(K+ε,σ(K+ε))))/ε〗 What is the analytical expression for the binary option value? σ(K)=const Therefore, Binary=lim┬(ε→0)⁡〖((C(K)-C(K+ε)))/ε〗 ...
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1answer
196 views

Valuation of Cox-Ross-Rubinstein Model

We have a Cox-Ross-Rubinstein model with parameters $u$ ("up"), $d$ ("down") , $r$ (interest rate) and $q$ (equivalent martingale probability) $(q=(1+r-d)(u-d)^{-1})$ . We have a contingent claim with ...
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2answers
225 views

stock option strategies long vs short

What makes an option strategy long or short? I got the impression that if it is a net debit (you pay to open the strategy) it is classified 'long' (strangle, straddle) Then I learned about the call ...
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1answer
283 views

In a covered call strategy, should I hold the call or sell/roll if the delta becomes too small?

I am tweaking a covered call algorithm. The short leg consists of out of the money call options. The goal is to collect the tim premium, but an equally favorable circumstance is when the call ...
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3answers
164 views

Computing loss of Call / Stock Purchase

A seller of an European Call, can, subjectively have unbounded losses. This loss may be mitigated by buying the stock (covered call). In this case,, the loss will be bounded at A. How would one ...
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1answer
162 views

Negative adjusted strike in Levy's Asian option approximation?

In Edmond Levy's 1992 paper, he introduced a moment-matching method to approximate the price of an Asian option assuming GBM for the underlying. It suggested that, if some monitor points are already ...
3
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1answer
61 views

Why risk-free interest is needed for Margrabe's Formula?

The source code for Margarble's formula in QuantLib is here. The implementation requires a forward price be computed: ...
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0answers
106 views

Pre- Versus post-2008 Crisis Rates Modeling

Modeling for interest rate derivatives (such as bermudan swaptions) is said to have undergone significant changes since the crisis. Prior to the crisis, counterparty default risk was often ignored, ...
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299 views

Does Bakshi, Kapadia and Madan (2003) VIX building approach underestimate volatility?

From a paper that shortly addresses an alternative approach to VIX-like index building: To test this approach, I've built a fake book of B&S options with constant volatility equal to $\sigma=...
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0answers
120 views

Estimating risk aversion (power or exponential utility) from options prices

I came across this literature and it seems like there are a number of ways people do this. You can do it for an option on any underlying as long as you can create the risk-neutral p.d.f. If you agree ...
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6answers
346 views

What is the Benefit of holding a short option?

i am new to corporate finance and ask myself why a investor is interested in being short on a Option? The only he can win is a premium but he can loose much more. I understand with being a short I can ...
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3answers
1k views

Understanding the concept of Martingale pricing

I am a bit confused about how to formulate a problem where I have to price an option on a stock. Many papers say that stock prices are best modeled using a geometric Brownian motion (GBM), and I ...
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2answers
56 views

Why would one prefer variance swaps over other instruments?

I understand that an investor who has a view on an underlying's variance would be tempted by a variance swap. But why would one prefer such a contract over another instrument whose value is based on ...
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4answers
218 views

How to short an option?

It appears to me that retail investors can only buy calls and puts, but not short them through any standardized way (except maybe borrowing the option from a friend ;) ). Is that correct, or how can ...
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2answers
245 views

Is it fair to assume $(ud=1)$ in the binomial tree option pricing model?

I have discussion with my colleague on why a general assumption $$ud=1$$ in binomial tree option pricing model would be necessary? I take it a simplification of the problem, otherwise, there will be ...
2
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1answer
100 views

Why is $N(d_2)$ not needed for hedging?

I'm trying to understand delta hedging. If I sell a plain vanilla call option, in order to delta hedge it, I have to buy delta amount of stocks. What I don't understand is that the BS price of the ...
2
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2answers
284 views

Is implied volatility flawed?

Was going through how Implied Volatility is used by option traders and in delta hedging. Correct me if I am wrong, doesn't IV consider a standard deviation of the stock price over say the past 1 year? ...
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2answers
1k views

Can we replicate a call option without borrowing and make it cheaper in this way?

I learned how to price a European call option using this video lecture. The considered case is very simple. The call option gives the right to buy 100 Euros for 100 Dollars in one month from now. The ...
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2answers
122 views

Carr-Madan Formula

Really new to financial Maths. I am currently having problems with the Carr-Madan Formula. $$f(S_T)=f(F_t) + f'(F_t) (S_T - F_t) + \int_0^{F_t} f''(K) (K-S_T)^+ \ d K + \int_{F_t}^{\infty} f''(K)...
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1answer
251 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.
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2answers
153 views

Short volatility strategy using strangles

For a short volatility strategy using option strangles, is it better to target a fixed premium to earn? Or a fixed vega? Objective is to maximise the return/risk (sharpe) of the strategy. Any help ...
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859 views

Daily option data

I am wondering where I can pull daily (hourly, by-the-minute, etc. even better) option data for a particular underlying. I would prefer a database I could scrape through and API, but would not mind ...
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2answers
95 views

Option pricing, origin of formula $\Pi( t,X)= E^{\mathbb{Q}}\left[e^{-\int_{t}^{T}r_s\,ds} X| \mathcal{F}_t\right]$

Imagine a model with stock prices and dividends of these stocks, as well as a market bond with associated short rate process. It is known that this model is arbitrage-free if there exists an ...
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1answer
248 views

Black Scholes Formula, drift term

In the formula, the stock return is modelled as a brownian motion that is a drift + a stochastic term, ok I get that. But the drift term is then modelled as r - volatility ^ 2 / 2. I am not sure how ...
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2answers
174 views

Exercise on American call option and dividends

Consider an americal Call option on an underlying paying dividends. Then it is often argued that it is only optimal to exercise right before the dividend is paid out, otherwise one will not exercise. ...
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1answer
100 views

How do I prove that $\lim_{K\searrow0}\frac{P(K,T)}{K} = \mathbb P(S_T=0)$?

I am trying to prove that $$\lim_{K\searrow0}\frac{P(K,T)}{K} = \mathbb P(S_T=0)$$ where $P(K,T)$ denotes the put option price with maturity $T$ and strike $K$ for some stock $S$. Assuming interest ...
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2answers
141 views

When can a derivative be considered to be path dependant?

The typical example of path dependant derivatives are knock-ins and knock-outs. At the same time vanilla American options can also be considered to be highly path dependant. Does a more or less ...