10
votes
3answers
1k views
At what point does someone using technical analysis become a Quant?
Sorry if the question sounds rough.
It's not my intention to devaluate something I've not yet understood like Quantitative Finance.
So to keep it simple:
is Quantitative Finance a science, like ...
10
votes
2answers
278 views
How to group timeseries showing similar curve
I am trying to classify similar looking curves of a timeseries and was wondering what is the best algorithm to research. Reading R, it looks like k-means clustering could be applied - but I don't know ...
10
votes
4answers
1k views
How do you evaluate a covariance forecast?
Suppose you have two sources of covariance forecasts on a fixed set of $n$ assets, method A and method B (you can think of them as black box forecasts, from two vendors, say), which are known to be ...
10
votes
4answers
625 views
Measuring liquidity
While liquidity is one of the key figure of financial markets, It seems to be very difficult to measure. Volume is sometime used as a proxy but can sometimes be completly irrelevant.
Could you point ...
10
votes
2answers
560 views
Reference request: Survey article on GPU in Finance
I would like to get and idea of how people use GPUs in finance.
I can find some specific papers or books on the subject.
GPUs in binomial model, finite difference, monte carlo,...
But I couldn't ...
10
votes
3answers
685 views
Rate interpolation in Libor Market Model
Libor Market Model (LMM) models the interest rate market by simulating a set of simply compounded, non-overlapping Libor rates which reset and mature on predefined dates. How do I obtain from them a ...
10
votes
4answers
1k views
What is a “coherent” risk measure?
What is a coherent risk measure, and why do we care? Can you give a simple example of a coherent risk measure as opposed to a non-coherent one, and the problems that a coherent measure addresses in ...
10
votes
5answers
446 views
Is it ever possible that---because of illiquidity---exercising an out-of-the-money option is better than directly buying the stock?
Is there a case, where due to illiquidity, exercising out-of-the-money options could be better than directly buying the stock?
When a stock is too illiquid, there are some costs because of this ...
10
votes
4answers
787 views
What books should any quantitative portfolio manager or risk manager have as reference? [closed]
I'm interested to know what are the critical reference texts you rely on for portfolio or risk management? I mean those texts that you come back to because they are chock full of insight and know-how. ...
10
votes
3answers
2k views
How to combine multiple trading algorithms?
Is it possible to combine different algorithms so as to improve trading performance? In particular, I have read that social media sentiment tracking, digital signal processing and neural networks all ...
10
votes
3answers
1k views
Is there an all Java options-pricing library (preferably open source) besides jquantlib?
I am looking for an all-java implementation of black scholes, preferably open source. I found jquantlib and quantlib (C++). Any other recommendations?
The jquantlib site seems to be down.
I'd prefer ...
10
votes
5answers
839 views
How to conduct Monte Carlo simulations to test validity of Black Scholes for a specific option?
In reference to the original Black Scholes model, what approach is best to test the model in a rigorous way? Is there a standard approach that can accomplish this in a reasonable amount of time?
...
10
votes
2answers
557 views
Missing step in stock price movement equations
Assuming a naive stochastic process for modelling movements in stock prices we have:
$dS = \mu S dt + \sigma S \sqrt{dt}$
where S = Stock Price, t = time, mu is a drift constant and sigma is a ...
10
votes
2answers
505 views
How to detect structural breaks in variance?
I'm looking for a method to automatically detect structural breaks, I tried Chow test, It
works good but it doens't work for breaks in variance.
Do you know a test to check strucutural break in ...
10
votes
2answers
574 views
How does one analyze diversification if stock prices follow a Cauchy distribution?
How does diversification actually lead to less variance in a portfolio? I'm looking for a formal reason why this is the case. There are a number of explanations I have been able to find, but they make ...
10
votes
3answers
897 views
George Soros models
Mr. Soros in his books talked about principles which are not used by today's financial mathematics — namely reflexivity of all actions on the market. Simply it can be given by following: ...
10
votes
3answers
2k views
What are the main limitations of Black Scholes?
Pls explain and discuss these limitations, and explain which models can I use to overcome these limitations. Alternatively, provide examples of how to modify the original Black Scholes to overcome ...
10
votes
3answers
732 views
How does UBS hedge its exposure to XVIX ETN?
I am wondering how UBS hedges its exposure to its ETN XVIX. Unless I am grossly overestimating the trading costs, executing the strategy they describe in their prospectus with futures would be quite ...
10
votes
3answers
687 views
Solving Path Integral Problem in Quantitative Finance using Computer
I've asked this question here at Physics SE, but I figured that some parts would be more appropriate to ask here. So I'm rephrasing the question again.
We know that for option value calculation, path ...
10
votes
3answers
557 views
What is the expected return I should use for the momentum strategy in MV optimization framework?
As all research on the momentum strategies are focused on the indicator, i.e. the entry point, there seems not much discussion on its expected return? Though there are some discussions on the exit ...
10
votes
2answers
587 views
How to forecast expected volatility from high-frequency equity panel data?
I'm wading through the vast sea of literature on realized volatility estimation and expected volatility forecasting (see, e.g. Realized Volatility by Andersen and Benzoni, which cites 120 other ...
10
votes
1answer
382 views
Issues when considering a quantitative trading/finance firm
I have an upcoming quantitative trading interview (prop desk at a large bank), and I would like to have some good questions to ask about the group. However, I am changing fields from academia and I do ...
10
votes
1answer
1k views
How do I compare implied and historic volatility?
what would you suggest are the starting points for comparing, in an easy, visual way, implied and delivered volatility surfaces? I'd like to see what the differences are between the historic surfaces, ...
10
votes
2answers
907 views
What are some computational bottlenecks that quants face? [closed]
What are the current computational (non-network) bottlenecks now in a quant's workflow? What computational tasks would be revolutionary with a 10-100x improvement in performance using general purpose ...
10
votes
1answer
294 views
Enhancing Monte-Carlo convergence (crude method)
I am currently doing a project involving Monte-Carlo method. I wonder if there is papers dealing with a "learning" refinement method to enhance the MC-convergence, example :
Objective : estimate of ...
10
votes
2answers
1k views
Is there a standard method for quantifying mean-reversion for use in directional trading?
Assuming a directional strategy (no pairs or spread trades) is there a "standard" method for quantifying mean-reversion? Should auto-correlation, variance ratios, hurst exponent, or some other measure ...
10
votes
1answer
259 views
What approaches are there for stress testing a portfolio?
Wikipedia lists three of them:
Extreme event: hypothesize the portfolio's return given the recurrence of a historical event. Current positions and risk exposures are combined with the historical ...
10
votes
2answers
735 views
How to build a regime-switching model which knows its own limits?
In recent months I've come to the conclusion that there are not only certain regimes in the markets (like bear or bull) but phases where all models fail because we are in uncharted territory. The ...
10
votes
2answers
779 views
Where to find Greeks for futures to form delta-hedged futures portfolio of S&P 500 index/futures
I can't find S&P 500 index (SPX) futures data with Greeks to create delta-hedged portfolios. Do these data exist? I have access to most of the common data sources.
In the meantime, I am trying to ...
10
votes
2answers
3k views
Cross Currency Swap Pricing in nowadays environment
Multicurve setting has now become the new paradigm for vanilla swap valuation. For the record I give here (without getting into too much details) the methodoloy for pricing Euribor3M swaps in this ...
10
votes
1answer
303 views
Model Validation Criteria
Let's say I have a brand new fancy model on some asset class (calibration porcedure included over a set of vanilla options) in which I truly believe I made a step forward comparing to existing ...
10
votes
2answers
672 views
Simulating Returns
I'll start this off with a rather broad question: I am trying to simulate returns of a large number of assets within a portfolio of different classes - equity and fixed income in a first step, say 100 ...
10
votes
2answers
837 views
Value-at-Risk of the sum of two dependent lognormal random variables
Hy I posted this question first at mathflow.net they suggested me this page, which I was not aware of.
Question:
Let $(X_1,X_2)$ be a multivariate normal random vector ($X_1$ and $X_2$ need not be ...
10
votes
1answer
212 views
How do you characterize dividends for equity options?
While many systems like to treat dividends as a continuous yield when pricing equity options, it works quite poorly for short-dated options.
In the short run, deterministic dividends are clearly the ...
10
votes
1answer
398 views
Any recommendations for textbooks for an undergraduate course in mathematical finance? [closed]
I'll teach an introductory course on mathematical finance in the near future. The course is intended to entertain and broaden some well-prepared advanced undergrad mathematics majors, some physics ...
10
votes
1answer
265 views
Is Arithmetic Return Bias Basis of Low Vol Anomaly?
An observation in capital markets is that the connection between return and risk (measured as volatility) is not that straightforward (at least not as modern portfolio theory assumes). One interesting ...
10
votes
2answers
341 views
Exploiting breakdowns in correlation of estimated volatility
In the attached image I have a plot of the rolling correlation of 90-day historic volatility (using the Garman Klass estimator based on Sinclair's Volatility Trading) of JPM v. the S&P. As can be ...
10
votes
1answer
306 views
Creating an n-factor Certainty Equivalent Discounting Formula
Brealey & Myers provide a certainty-equivalent version of the present value rule, using CAPM, as follows:
$$PV_0=\frac{C_1 - \lambda_m *cov(C_1, r_m)}{1 + r_f}$$
$PV_0$ - Present Value of cash ...
10
votes
1answer
210 views
What weights should be used when adjusting a correlation matrix to be positive definite?
I have a correlation matrix $A$ for an equity market that is not positive definite. Higham (2002) proposes the Alternating Projections Method, minimising the weighted Frobenius norm $||A-X||_W$ where ...
10
votes
0answers
141 views
A non parametric study of VaR with kernel density
I'm working in order to compare the calculation of the VaR between the methodology of copulas and kernel density, all this by using the software r.
The process that I follow is:
Obtain a sample ...
10
votes
0answers
326 views
Law of an integrated CIR Process as sum of Independent Random Variables
It is known (see for example Joshi-Chan "Fast and Accureate Long Stepping Simulation of the Heston SV Model" available at SSRN) that for a CIR process defined as :
$$dY_t= \kappa(\theta -Y_t)dt+ ...
9
votes
4answers
2k views
What is a martingale?
What is a martingale and how it compares with a random walk in the context of the Efficient Market Hypothesis?
9
votes
5answers
933 views
When to shut down a trend following strategy?
Suppose I have trend following strategy(on close to close data) that is not getting acceptable returns for some time. When should I start thinking about shutting it down?
9
votes
3answers
825 views
How to optimally allocate capital among trading strategies?
I'm trying to find an optimal way to allocate capital among trading strategies.
"Quantitative Trading" by Ernie Chan claims on page 97 that the optimal fraction of capital to allocate to a given ...
9
votes
6answers
2k views
How high of a Sharpe ratio is implausibly high for a low-frequency equity strategy?
I am looking to convince someone that an annualized Sharpe Ratio of 7 is 'extremely high' for a low frequency (daily rebalancing, say) long-short technical strategy on U.S. equities. I was hoping for ...
9
votes
6answers
834 views
How to generate a random price series with a specified range and correlation with an actual price?
I want to generate a mock price series. I want it to be within a certain range and have a defined correlation with the original price series.
If I choose, say, oil, I want as many time series which ...
9
votes
5answers
2k views
What is the implied volatility skew?
I often hear people talking about the skew of the volatility surface, model, etc... but it appears to me that a clear standard definition is not unanimously in place among practitioners.
So here is ...
9
votes
7answers
683 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 ...
9
votes
3answers
905 views
Why do expected return models and risk models use different factors?
This is a question responding to weekly topic challenge. I happen to see an interesting question from SYMMYS by Michael Kapler.
I always approached expected return and risk modeling as separate
...
9
votes
4answers
2k views
Should Sharpe ratio be computed using log returns or relative returns?
I am trying to reconcile some research with some published values of 'Sharpe ratio', and would like to know the 'standard' method for computing the same:
Based on daily returns? Monthly? Weekly?
...
