Questions tagged [correlation]

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

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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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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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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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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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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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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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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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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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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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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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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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531 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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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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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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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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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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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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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),...
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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 ...
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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 already ...
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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 ...
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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 ...
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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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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 ...
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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 ...
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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 ...
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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 ...
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Can the Minimum Variance Hedge ratio be greater than 1?

The Minimum Variance Hedge ratio is defined as: $h = \rho * \frac{\sigma_S}{\sigma_F}$ For correlation $\rho$ and $\sigma_S , \sigma_F$ for S.D. of changes in asset and future prices accordingly. ...
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Regime Switching for Dynamic Correlations

I would like to implement a Regime Switching for Dynamic Correlations in an out-of-sample analysis using MATLAB. After looking at the literature on the subject, they all refer to an article by Denis ...
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How can I forecast future correlation?

There are some standard models for forecasting volatility (e.g., GARCH) and for forecasting returns (e.g., factor models). What kind of standard models exist for forecasting future correlation between ...
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Time-Varying Copulas (GAUSS)

Could anyone suggest me how to begin with Time-varying Copulas or Stochastic Copulas? I'm looking for the GAUSS code, however it seems there are only MATLAB code available over the internet. I'm ...