A measure of the degree of linear association between a pair of random variables.

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56 views

Correlation between asset A and Portfolio X (which contains A)

After a few hours trying to solve this I give up! I need help. I need to calculate the BETA of an asset with respect to a portfolio that contains this asset. I have the volatility and correlations ...
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2answers
42 views

Creating index from bloomberg data in matlab

I'v got 6 different equity index time series from which I want to create an index based on a particular percentage. This would be simple although due to different holidays the date don't always match. ...
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2answers
28 views

Correlation of Asynchronous Brownian Motion

I am trying to use the closing prices of the S&P 500 and the Nikkei Index to see how they are correlated (assuming they are exactly 12 hours apart). In order to test my method, I have generated ...
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2answers
69 views

Correlation between 2 stocks [closed]

If Stock A returns 5% on average in year Y And Stock B returns 2% on average in year Y Does this mean that correlation is 40%?
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2answers
59 views

Correlation: Use Price or Return? Return doesn't make sense [closed]

I am trying to find the correlation between the returns of two indices over a long period of time (10 years+) . Should I be using the index daily price level or the index daily total return? Most ...
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0answers
30 views

Adding negative EV position to portfolio for diversification?

Say I have a portfolio of expected return $10%$ and volatility $20%%. If I have another asset that is either one of: Negatively correlated Positively correlated Uncorrelated With negative expected ...
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0answers
46 views

serial correlation, Fama MacBeth (1973) procedure incorporating momentum

I have a question regarding the use of the Fama-MacBeth (1973) procedure on panel data. I am investigating the cross sectional determinants of expected REIT return following the procedure from: Chui, ...
3
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1answer
75 views

What is the covariance of two correlated Ornstein-Uhlenbeck processes?

What is the covariance of two correlated Ornstein-Uhlenbeck processes? I was trying correlation(1,2)*Var1^(1/2)*Var2^(1/2), but I am not sure! I took ...
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17 views

Correlation coefficient for different functions

Can somebody explain the correlation coefficient values for the following set of functions $x and $y? -Independent Functions -Asymptotically Dependent Functions -Marginal Functions -Normally ...
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0answers
29 views

In May of 2005, several large hedge funds had speculative positions in CDO tranches

These hedge funds were forced into bankruptcy. This was due to: the correct answer is: Long Mezzanine and Short Equity Tranche position when correlation of Mezzanine tranche decreased. Can anyone ...
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8answers
8k views

Time-series similarity measures

Suppose I have two time series $X$ and $Y$ of stock prices. How do I measure the "similarity" of $X$ and $Y$? (I'm being deliberately vague as I don't have a particular application, and I'm curious ...
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34 views

Exponentially weighted random matrix - which variance should I use?

I am currently playing around with exponentially weighted correlation matrices and filtering based on Random Matrix Theory. However, there is one thing I am not really sure about: In the equation ...
4
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1answer
574 views

How to calculate implied volatility smile of basket using correlations?

For a basket, the realized volatility can be calculated using: $$\sqrt{\sigma_1^2 + \sigma_2^2 + 2 \sigma_1 \sigma_2 \rho}$$ If I have the volatility surface of two underlyings S1,S2 (strike space). ...
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2answers
69 views

Bounded Stochastic discrete process

I just came across this stochastic process (link): $dY_t = (a-bY_t)dt + c \sqrt{Y_t(1-Y_t)}dW_t$, where $dW_t$ is a Wiener Process. According to the author under certain conditions this process is ...
4
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2answers
117 views

Two correlated brownian motions

Is it true (see here, footnote 2, p.22 / p.14, without proof) that we can obtain two discretized brownian motions $W_t^1, W_t^2$ with correlation $\rho$ by doing $$d W_t^1 \sim \mathcal ...
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1answer
47 views

Deriving the single factor model

Consider the following regressions, with the common factor $x$: $y_1 = \beta_1 \cdot x + \gamma_1 \cdot \epsilon_1 $ $y_2 = \beta_2 \cdot x + \gamma_2 \cdot \epsilon_2 $ With $\epsilon_1$, ...
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0answers
41 views

Correlate the G2++ with a GBM model

In Matlab one can use the LinearGaussian2F function together with the simTermStructs function to create a simulated zero curve based on the G2++ model. Next to simulating the interest rates I need to ...
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0answers
14 views

building a correlation of equity portfolio to custom benchmark 60/40

Hi i have built a custom portfolio of equities with weights but would like to plot the daily, monthly and annual correlation to 60/40 benchmark. Please see code below and suggest how I can do the ...
11
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1answer
574 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 ...
2
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1answer
70 views

decompose correlation swap pnl

For a Variance swap we can split the pnl into a realized part and a "forward going" part. To be more precise: Assume we enter the trade at t0, and the variance swap has tenor T and a strike $Kvar$. ...
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0answers
17 views

Monte Carlo - Inflated Asset Paths Due to Correlation

I built a MC generator for 12 assets based on Brownian Motion and noticed some strange results. Formula Used S(t) = Exp(S(t-1) + (mean - (vol. / 2)) + (stdev * Normal Distribution #)) S(0) = Ln(1) ...
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0answers
31 views

Portfolio Analytic Metrics for Portfolios with Serially Correlated Returns

I just read Andrew Lo's paper from 2002 "The Statistics of Sharpe Ratios" and am wondering if anyone knows of any other papers/docs/resources that explore the impact of serially correlated returns on ...
4
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1answer
61 views

market change, correlation and estimation bias

I hear many quants sating that markets change very slowly. This "fact" is even presented as a justification of statistical arbitrage, for example, by affirming that correlations remain roughly the ...
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3answers
336 views

Why do volatility and correlation increase in times of crisis?

can somebody please explain to me why volatility and correlation increase in times of crisis? It is connected somehow to the herding effect. But I cannot really explain it. And also why are negative ...
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29 views

Measuring strength of correlation for bivariate time series

In case of a bi-variate time series with both I(0) how do I measure the strength of co-relation. I am looking for measure similar to R-squared but ideal measure may not be one of the variants of ...
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35 views

What is the standard length for rolling correlation in financial time series?

I know this is highly subjective, but is there any theory behind choosing a window period for rolling correlations? If I do 1-day or 2-day rolling correlations between highly correlated positions, ...
9
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1answer
133 views

Estimate Beta of CAPM from Implied Volatility?

In the CAPM theory Beta of asset $i$ are estimated in this way: $ \beta_i = \frac{\sigma_{im}}{\sigma^2_m} $ where $\sigma_{im} = \rho_{im} \sigma_i \sigma_m$ But all these data are historical data. ...
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218 views

What is the preferred GARCH method in practice?

My advance apologies, if this question is too naive or basic. Please be patient with my first experiences with SE; ask for clarification, if needed. I recognize there are many (often-criticized) ...
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0answers
21 views

Stochastic correlation arbitrage-free replication

I'm interested in possibility of stochastic correlation arbitrage-free replication (something VIX-style, mayby). To my knowledge, no such method exists. Could you provide some intro to the problem: ...
2
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1answer
288 views

How to create a basket of currency pairs with the lowest correlation in R?

My strategy is designed to buy and sell all assets of a universe and rebalance periodically. It goes either long or short. To limit risk exposure to a single currency I would like the assets in the ...
3
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1answer
100 views

volume-returns cross correlation interpretation

I want to find the relationship between volume and price returns in the S&P500. My first thought was to run a cross correlation in order to find who leads and who lags in the relation. It´s my ...
3
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1answer
25 views

How to distinguish true negative eigenvalues from small negative eigenvalues due to floating point error?

Floating points have rounding errors so algorithm to find eigenvalues may report tiny negative eigenvalues but in reality thsee could actually be 0 if we had full precision. Any way to tell ? I have ...
2
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2answers
62 views

Why do CFDs track the underlying?

My understanding of CFDs is that the profit you make on a CFD is the difference between the price at which you bought the CFD and the price at which you sold your CFD minus various charges/commission. ...
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0answers
57 views

Why is credit exposure higher for a smaller probability of default than for a larger default?

I'm having trouble grasping this concept; I don't see the relevance of the explanation given in the text (Gregory, Counterparty Credit Risk and CVA) either. When expected exposure and probability of ...
2
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2answers
112 views

What do you do with low r-squared when calculating high-frequency beta

I am calculating a high-frequency beta. For example I have 90 days of data of the S&P and GOOGLE and I have 10-minute percent returns for each instrument. Each day has 34 10-minute percent returns ...
0
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1answer
58 views

What is the correlation of stock options?

I want to calculate the VaR of two correlated option positions, and I know the correlation between stock price returns. I want to separately calculate $Var_1$,$Var_2$ for option 1 and 2, and then use ...
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0answers
40 views

Good broad review of network modeling for quant finance?

Trying to find some good review of agent-based models for quantitative finance, covering opinion dynamics, correlated behavior, etc. Are there any articles or books that cover major advances in these ...
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1answer
196 views

When measuring autocorrelation should you use log returns or prices?

Let's say you want to measure intra day autocorrelation from 9:30 am to 1pm using 5-minute prices should you calculate the autocorrelation using raw prices or log returns (i.e. diff(log(prices)))? Can ...
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2answers
73 views

Correlation Between 2 Portfolios

I have a set of assets, n. I'm trying to find the correlation between 2 portfolios, say x and y, where x is nested in, or, a sub-set of y. That is, x is a portfolio based on a sub-set of n, while y is ...
2
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1answer
99 views

Estimating correlation using EWMA

I am using an EWMA model to evaluate the correlation between yearly time series. I know Riskmetrics uses $\lambda=0.94$ for daily data and $\lambda=0.97$ for monthly data. Is there a value ...
5
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2answers
135 views

Interpretation of Correlation

I have two geometric Brownian motions (GBMs) driven by the same underlying Brownin motion, namely \begin{align*} S_t^1 = S_0^1\exp\left(\left(\mu_1 - \frac{\sigma_1^2}{2}\right)t + \sigma_1 ...
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1answer
67 views

bootstrap asset allocation

I want to ask if the bootstrap method for asset allocation is preferable. For instance, suppose that we have data for the past returns for two stocks. Is it wise to generate the efficient frontierby ...
0
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2answers
102 views

Right metric to manage a portfolio based on correlation?

I want to algorithmically add a new investment to an existing portfolio. The decision should be based on a low correlation to the existing assets. E. g. the following situation The portfolio ...
5
votes
3answers
793 views

Is there a copula that can estimate negative tail dependence?

I have encountered numerous copula estimators that can estimate time-invariant and time-varying linear and non-linear correlations on the interval $[-1,1]$, and these estimators are fully consistent ...
2
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2answers
4k views

Why do stocks with a negative beta return less than the risk free rate?

Let's say we have two stocks, Stock A and Stock B. Both of them have the same standard deviation $\sigma$, and therefore have the same risk. The only difference is that Stock A has a perfect ...
0
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3answers
45 views

Small question about normalization

Lets assume I want to normalize some stock data ( prices or log prices) to compare for different types of correlation for example. And here is the question how should I normalize: a) by subtracting ...
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2answers
97 views

Garch for covariance matrix?

I have seen plenty of literature about GARCH on estimation volatility. how about covariance? There are plenty of risk models depending on the covariance matrix. I guess we can assume the correlation ...
2
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1answer
109 views

How to account for correlation between strategies when they are added linearly?

There are n strategies which are going to be combined linearly. Using a pre-exisiting model I get a set of n weights which will be used to combine the strategies. But the model does not take ...
3
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2answers
389 views

correlation for portfolio of stocks

I have a portfolio of stocks and all I want to do is to make sure that I'm not trading one big position, so I would like to monitor some type of metric that gives me a rough idea of what the overall ...
2
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2answers
131 views

hedging correlated instruments

If two instruments have a significant negative correlation but the percent change in the price of the instrument moving in positive direction is always more by a fraction than the one moving in ...