Questions tagged [correlation]

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

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119 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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Why does the presence of cointegration solve the problem of spurious correlation? [closed]

Many of us are familiar with the connection between spurious correlation and its relationship to cointegration. Granger explains in his seminal 1974 paper "Spurious Regressions in Econometrics" how ...
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Portfolio of single stock short put options: which correlation structure preferrable?

Let's say you want to have a equally-weighted (in terms of the option price) portfolio of short put options on various stocks with the same maturity. Running Monte-Carlo simulations, it seems that ...
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537 views

Low beta and high correlation

Assuming that time period used to calculate the beta and correlation between an index and an asset is the same, is it possible to observe low beta while having high correlation? If yes, how would ...
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258 views

Correlation between two indexes

The Global Minimum Variance has an annual return standard deviation of 9.9%. Its correlation with the Standard & Poor's 500 Index is 0.45. What is the annual return standard deviation of the S&...
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4k views

Do two stocks with the same beta have a correlation of 1?

If two stocks have the same beta over same time period, does it mean they are 100% correlated over that time period? In a CAPM framework, a stock's beta is defined as $$\beta_1={\rm Cov} (R_1, M) / {...
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43 views

Simulating Co-Integrated Assets

I know how to simulate correlated returns, but I do not know how to simulate Co-Integrated assets. I would like to simulate a co-integrated time series where the Beta Co-Efficient is not constant, but ...
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1answer
74 views

Decreasing dependence during the financial crisis?

In "Is the Potential for International Diversification Disappearing? A Dynamic Copula Approach" by Christoffersen et al. (2012), the authors present the concept of Conditional Diversification Benefit ...
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1answer
198 views

Computing Correlation between Forward Rates

I have the feeling this question has an extremely simple answer but I'll put it out to the group anyway. Imagine I have data for 3M and 6M forward rates following a lognormal process, and that I ...
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2answers
110 views

Co integration of diverging time series

I have 2 time-series datasets. I am trying to find co integration between them. Now the thing is they are negatively correlated. So if I want to look at the distance between them, would I be right in ...
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68 views

Puzzler on construction of a 2-stock portfolio

Lets say you get to choose any 2 stocks. Is it possible that a portfolio can be built from the two stocks (long or short either, any weighting) that has a lower volatility (standard deviation of ...
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531 views

FX Forward pricing with correlation between FX and Zero-Cupon

I would like to extend my question about about FX Forward rates in stochastic interest rate setup: FX forward with stochastic interest rates pricing We consider a FX process $X_t = X_0 \exp( \int_0^t(...
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908 views

How to estimate an Engle's asymmetric DCC model in R?

I have a $N x d$ matrix of standardized residuals, and I want to estimate the parameters $\alpha$, $\beta$ and $\gamma$ of the asymmetric version (Cappiello, Engle, Sheppard, 2006) of the usual ...
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369 views

Average Correlation

We're given a spreadsheet with a correlation matrix for four stocks. Then there is a calculation for average correlation, but I don't know how it's derived. $$=\left(\operatorname{Average}(C14:F17)-\...
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How exactly are correlated defaults used/analyzed?

I've read a lot about correlate defaults but I can't seem to understand how they're used practically in a portfolio theory setting. Suppose I have two (?) companies, X and Y, and historic default ...
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1answer
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Why do two perfectly negatively correlated assets not return 0%? [closed]

So, per the title, why would a combination of two risky assets that have the same exact expected return and standard deviation while being perfectly negatively correlated not return 0%? Why do you ...
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How to replicate a correlation swap using only vanilla options and underlying

Assume I have two assets A and B that are positively correlated most of the time. I'm trading a strategy based on this correlation. Is there a way to protect myself in the event that the correlation ...
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1answer
694 views

Correlation of a lognormal asset and a normal asset

So if i want to calcualte the correlation between a pair of assets, my intuition is that i should calculate whatever correlation i plan on using; When we look at correlation, it's normally the ...
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421 views

Normalization of Market Data in Time Series Correlation

Suppose we have 2 time series of market data, one for each security and we want to correlate between these 2 securities. My question is How do we handle gaps of missing data in the time series? ...
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Account for empirical relationship between signal and market data

I have two monthly time series : one is a 'signal', on which I will base my decision to buy or short-sell, and the second one is the time serie of a given asset's price. I have implemented this ...
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290 views

Are two stochastic processes independent if the Wiener processes inside are uncorrelated

Assume there are two stochastic processes: $dx_t = \alpha_1(x_t,t)dt + \beta_1(x_t,t)dW^1_t$ and $dy_t = \alpha_2(y_t,t)dt + \beta_2(y_t,t)dW^2_t$. Does $dW^1_t\times{dW^2_t} = 0$ imply that $\...
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1answer
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Why does the correlation between r and V in Longstaff and Schwartz 1992 model is positive?

I am reading the Longstaff and Schwartz's 1992 and 1993. From $r = \alpha x + \beta y$ and $V = \alpha^2 x + \beta^2 y$. It was mentioned in the paper that the $r$ is positive correlated with $V$. ...
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319 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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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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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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579 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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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, ...
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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 Var1=(sigma1^2/(2*speedofmeanreversion1))*(1-exp(-...
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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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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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2k 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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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 ...
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335 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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817 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 ...
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484 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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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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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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1answer
844 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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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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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 ...
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171 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 ...
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1answer
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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 ...
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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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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 ...
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2answers
408 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 ...
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1answer
181 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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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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2k 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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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 ...
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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 W_t\right),...