# All Questions

373 views

### Typical coefficients uses in square-root model for market impact

The square-root model is widely used to model equity market impact. It assumes that volatility, traded volume, total volume, and a spread cost are the drivers of slippage. Jim Gatheral has an ...
852 views

### When hiring a quant, how can I protect my IP?

I am a one-man operation, and would like to hire a quant for around 4 weeks or work. I am worried that the person I hire might copy my data or the indicators that I have him work on. What have ...
319 views

### Avoiding negative volatility when applying Heston model

When applying the Heston model to generate the sample volatility surface, some of the volatility value will be negative. I am just wondering what do practioners normally do with these negative value. ...
438 views

### The Basis of Using Technical Indicators as Inputs

In the process of my research I very often come across academic papers regarding modelling and trading strategies that in one way or another incorporate some technical indicators. For example in some ...
382 views

### Which prediction market model is efficient and simple to use?

For a college project I'm tasked with implementing prediction market. Which model of it I'd better choose? I want something useful and simple enough for other people to quickly understand and use. ...
113 views

### Basel CVA VaR with R/WWR

In Basel III the CVA VaR “is restricted to changes in the counterparties’ credit spreads and does not model the sensitivity of CVA to changes in other market factors, such as changes in the value of ...
221 views

### Analyzing the angle between vector of weights and vector of returns in mean-variance optimization

I am using the paper "A Sharper Angle on Optimization" by Golts and Jones (2009) as a basis for my (minor) masters thesis in mathematical finance. The paper focuses on the mean-variance analysis of ...
1k views

### What are the advantages/disadvantages of these approaches to deal with volatility surface?

I would like to know if someone could provide a summarized view of the advantages and disadvantages of the approaches on the volatility surface issues, such as: Local vol Stochastic Vol ...
148 views

### How to simulate one-minute bars data from one-day bars?

I need to generate one-minute bars out of one-day bars to test the performance of an algorithm (speed, memory usage, etc). I don't need them to resemble real data, but they should be consistent with ...
3k views

### Is the stock price process a martingale or a Markov process?

Some people claim that the data-generating process for stocks is a "martingale" and that is has the "Markov property". Are they unrelated? Is it that the Markov property implies some sort of ...
348 views

### Delta of a Down and Out Call

I came across some graphs depicting the delta of a down-and-out call. They show that, if the risk free rate of return is 0, the delta is constant at 1. However, if the rate of return is for example ...
1k views

### What is the mean and the standard deviation for Geometric Ornstein-Uhlenbeck Process?

I am uncertain as to how to calculate the mean and variance of the following Geometric Ornstein-Uhlenbeck process. $$d X(t) = a ( L - X_t ) dt + V X_t dW_t$$ Is anyone able to calculate the mean ...
176 views

### Sharpe ratio in days with no open positions

Should I include or not the days a strategy has no open positions (thus no returns) in the Sharpe ratio calculation?
490 views

### CTD and bond futures

I am reading a chapter on bond futures in Fabozzi's book. It states that without CF (conversion factor) the CTD (cheapest to deliver) would be the bond with the longest maturity and highest coupon. ...
245 views

### What is the canonical reference for Minimum Variance Portfolio's uniqueness?

I am writing a white paper in which I am trying to compare a strategy to different well-known - and classic - asset allocation optimization approaches. One of the methods I chose is the minimum ...
889 views

### How to detect regime change when estimating asset correlation from historical time series?

Suppose I have two asset time series, $X_t$ and $Y_t$, and I'm estimating their correlation from historical data. I'd like to apply some systematic criterion to estimate what time window I should use ...
260 views

### Alternative ways to understand time-varying comovement between two time-series?

I have been looking into ways to better understand how the dependencies/correlations/etc between two time series can vary over time. I first thought about using a Kalman/particle filter over a ...
275 views

### Generate correlated random variables from Normal and Gamma distributions

I want to generate a random vector $z$ of dimension $k+m$ with some given correlation matrix $\Sigma$, such that the first $k$ elements of the vector are distributed normally and the last $m$ elements ...
373 views

### Squared and Absolute Returns

I've always wondered why do one use squared or absolute returns to determine if volatility modeling is required for the return series? We understand that there are various tests for its ...
324 views

### Selecting timeframe for time series analysis

In technical analysis, we may use confluence of direction for 3 timeframes to roughly gauge bias of market now. Similarly, if we use time series forecasting methods to predict(say daily data-whether ...
1k views

### How do we use option price models (like Black-Scholes Model) to make money in practice?

In quantitative finance, we know we have a lot of option price models such as geometric Brownian motion model (Black-Scholes models), stochastic volatility model (Heston), jump diffusion models and so ...
1k views

### Methods for pricing options

I'm looking at doing some research drawing comparisons between various methods of approaching option pricing. I'm aware of the Monte Carlo simulation for option pricing, Black-Scholes, and that ...
93 views

### Volatility Index Weighting Scheme

Among the several weighting schemes used for constructing volatility indices, which ones are the best for forecasting (realized) volatility? I've constructed a volatility index for emerging markets ...
448 views

### Oscillatory time-series forecasting

I was wondering if this mean(160)-reverting/oscillatory time series "SUM" can be considered chaotic & forecastable to some extend short-term? ...
125 views

### Pricing swaptions

What are the approaches available to price a swaption (either European or American style)? So far it seems Black method is the only one used. Thanks!
297 views

### What data transformations to use in regression of credit spreads on equity prices?

Clearly there is a strong relationship between credit spreads and equity prices (both theoretically and empirically). But how would one go about formulating a regression which seeks to explain this ...
2k views

### portfolio optimisation with VaR (or CVaR) constraints

I would like to optimize a portfolio allocation (maximizing the exposure or the expected return), but with VaR or CVaR contraints. (some parts of my portfolio cannot exceed a certain VaR) How can I ...
1k views

### Why is short term implied volatility typically higher?

Why do short term implieds move more than long term?
481 views

### Regressor: Nominal return, continuous return or first difference?

Suppose the application is linear models in financial econometrics. If we want to analyze stocks, the standard approach is to take the continuous/log return: $\ln{ \frac{P_t}{P_{t-1}} }$. Suppose, ...
664 views

### What is the clean price and dirty price of a risky bond?

Following up on this question: Yield of a risky bond, what is the definition of clean and dirty prices for a risky (defaultable, catastrophe, etc.) bond? I would think the dirty price should ...
244 views

### Asymmetric Volatility Modeling (Interpretation)

I am currently writing a paper on asymmetric volatility modeling of brent, gold, silver, wheat, soybean and corn from 1986-2012 and divided them into 4 sub-sample periods (i.e. 1986-1991, 1991-1997, ...
918 views

### What does the VIX formula measure and how does it work?

I have read the CBOE's white paper on the VIX and a lot of other things, but I need to honestly say, I don't really get it, or I am missing something important. In semi-layman's terms, is the VIX ...
583 views

### What is the “leverage effect” for stocks?

I've read the so-called "leverage-effect" for stocks models the fact that if a company is leveraged, its volatility should increase as the stock price moves lower and closer to the level of debt. Can ...
132 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).
343 views

### Regime switching in mean reverting stochastic process

Let you have a mean reverting stochastic process with a statistically significant autocorrelation coefficient; let it looks like you can well model it using an $ARMA(p,q)$. This time series could be ...
1k views

### Longstaff Schwartz method

I try to implemente the LSM method with this algorithm but my price is always too low. By example for an American put option with the following parameters: S0 = 36, Strike = 40, rate = 6%, T = 1 ...
165 views

### Reasonable Hull & White parameters

I am using a Hull & White model to simulate forward rates on US swap curve from the 1.10.2012. This is a part of a bigger picture, and I am interested in some reasonable values for the parameters ...
80 views

I was looking at this video today: http://www.cmegroup.com/education/interactive/webinars-archived/implied-price-functionality.html on implied pricing. And am aware that implied orders/pricing ...
168 views

### How to see if a set of asset returns corresponds to a known correlation matrix?

Let's say I have an arbitrary set of $n$ period returns for $k$ assets, and a given $k \times k$ correlation matrix (of asset returns), which is known a priori. Does it makes sense, or is it even ...
959 views

### Fastest solver possible for portfolio optimization

I am using quadprog in MATLAB for very simple mean-variance optimization, with less than 100 assets. It is quite fast but if I run a strategy with daily ...
387 views

### Yield of a risky bond

When working with risky bonds, i.e. corporate bonds, what is usually defined as the yield of such a bond? Is it the yield calculated as if the bond was riskless, or is it calculated by properly taking ...
162 views

### Inflation swap liquidity versus inflation-linked bonds

In which markets are inflation swaps considered liquid enough to be the primary instrument for measuring market inflation expectations (compared to say, inflation-linked bonds)? Are there specific ...
287 views

### Rubinsteins Implied Binomial Tree - how to calculate the cumulative returns

I am working on Rubinsteins IBT and use the following paper to implement this into excel: http://papers.ssrn.com/sol3/papers.cfm?abstract_id=541744 the original paper can be found here: ...
467 views

### Given two portfolios with identical correlation matrices, which one will have a better risk/reward ratio?

I have one portfolio with high beta stocks, and one with low beta stocks. Is it better to have higher expected return with high volatility, or medium expected return with medium volatility? (All from ...
80 views

I found this comment in a book I bought about risk management: Risk Management in Banking by Joel Bessis. This is the well-known rule that states that the sum of individual risks is less than ...
360 views

### Optimizing a currency only portfolio with negative weights

I am testing various optimization methods for a currency-only portfolio. I have a vector of expected returns for the major developed currencies vs. the USD each week (based on a proprietary model). I ...
1k views

### Fastest algorithm for calculating retrospective maximum drawdown

Simple question - what would be the fastest algorithm for calculating retrospective maximum drawdown ? I've found some interesting talks but I was wondering what people thought of this question here. ...
15k views

### What are some examples of non-financial risks and contingency plans?

There are many online sources about common risk factors in investing and trading e.g. market risk, credit risk, interest rate risk. There are various factor models (Fama-French, Carhart) and risk ...