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

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22 views

Inflation/Rates Correlation

I've been looking into a short piece of maths a colleague has written on pricing inflation with payment delays, and was hoping someone could confirm whether my understanding is correct, or if my ...
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1answer
48 views

Does the correlation of matrices has explanatory power when building a pattern recognition model?

I'm using 8 different variables (with daily observations) with the purpose to compare different months across the historical data. For that purpose I calculate the correlation between each month and ...
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1answer
81 views

Analog - Pattern Recognition model using KNN

I'm building a pattern recognition model for my master thesis. The idea is to build a framework with some Macro variables (long/short term rates; rates differential; equity; fx; vix) in order to find ...
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1answer
41 views

Hedging using relative values

Consider I have two stocks $A$ and $B$, $A$ is trading at $\$40$ and $B$ at $\$30$. The standard deviation of its returns are $\sigma_A=25\%$ and $\sigma_B = 30\%$. Correlation between the returns is ...
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1answer
44 views

What is Base- vs. Implied Correlation of a CDO tranche?

What is the difference between Base Correlation and Implied Correlation for a CDO tranche?
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47 views

Is this a reasonable approach to determine the relative importance of valuation factors?

I am trying to come up with a measure of relative importance of a number of valuation factors. I am wondering whether correlation coefficients can't be used for determining this. More on the issue: ...
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1answer
70 views

Estimate correlation of time series whose histories differ in length

Very often in quantitative analysis (e.g. calculating portfolio volatility) we have to analyze various time series - mostly returns - whose lenghts differ. Risk systems usually apply a one-factor ...
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1answer
109 views

Explain drop in Correlation between two time series in consecutive periods

I have a time series for a security list with 2 parameters calculated for each time period. For example, for a stock XYZ, I have Param1 and Param2 calculated over various time periods stacked against ...
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1answer
60 views

Correlation Multiple Currencies

If i have a portfolio of stocks from different currencies and i want to generate a correlation matrix from the stocks, how is the correct procedure ? Imagine a portfolio which the base currency is ...
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2answers
218 views

Correlation between S&P500 returns and 10y US Treasuries yields

I'd like to investigate the comovement of stock index returns with bond yields but I don't know which return's duration to use (1-year, 1-month or anything else) to get a better view of the ...
2
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1answer
88 views

Correlation of asset to portfolio, given certain variables

Ultimately I'm trying to calculate stdev contribution, but I've hit a hurdle. What I have: 20x20 correlation matrix for various assets Standard deviations for each asset Returns for each asset ...
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64 views

Correlating random numbers seems to skew the data

First off, apologies for the cross-post from mathematics, but I found this site later and think it would be a better fit for the question (besides, there has been no comments/answers on mathematics ...
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2answers
157 views

2 stocks, no shorting vs shorting. (concrete questions, mean-variance)

I'd appreciate help with the following questions. Suppose there are two stocks $A$ and $B$ with expected returns $E_A, E_B >0$ and volatilities $v_A, v_B >0$, respectively . Also, suppose ...
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1answer
66 views

Sample size and historical correlation matrices

I was wondering whether any literatures existed on how to properly estimate correlation matrices from historical data. Obviously the entire procedures allows a lot of leeway. The frequency of ...
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2answers
62 views

Implied Correlation using market quotes

Is there a way to retrieve the implied correlation between stock price and zero coupon bonds?
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1answer
147 views

High correlation will help detect spurious regression over cointegration?

I'm analyzing two financial time series with Johansen method. A high Correlation coefficient using the Pearson method will help me to detect spurious cointegration models to avoid? If this is not ...
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3answers
269 views

Calculate correlation between two sub portfolios and the combined portfolio

I have two sub portfolios (lets call them portfolio a & portfolio b - a portfolio is just a vector of weights that sum to 1) that combine to create a total portfolio. I also have a 2 x 2 ...
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1answer
169 views

Given a correlation martrix, calculate portfolio's correlation with its assets

Find correlation vector like $[ d e f ]$ where d, e and f represent correlation of P(portfolio) with its assets A, B and C respectively. The assets A, B, C can be another portfolio. In order for ...
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1answer
91 views

Partition assets into minimally correlated portfolios

My question covers a more or less classical portfolio optimization situation with a twist: How to partition assets into minimally correlated portfolios, with and without asset overlap. I have $N$ ...
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2answers
96 views

Harnessing small correlations for reliable profit

It is said that Edward O. Thorp was able to harness small correlations for reliable financial gain. I've seen some strategies based on strong correlations which did not seem particularly reliable. ...
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134 views

Is there a Newey West like correction for overlapping data correlation estimates?

I already posted a related question a while ago but was unsure if I should post within the same question. I want to estimate mulitperiod asset return correlations and test if there are significant ...
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2answers
360 views

Why does it “say” portfolio diversification not suitable during market turmoil?

Currently I am trying to get a hold of MPT, asset allocation and related applications. While reading a particular resource, it says diversification works best for "normal" financial markets and ...
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1answer
80 views

Can we model components in a set of multivariate multi-period time-series data?

There are N data sets in periods occurring weekly/monthly, across a 10-year historical timeline. In each period, five dates are observed (labelled a to e), where a denotes the day the period ...
2
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1answer
231 views

Need overlapping sample autocorrelation correction for calculating asset return correlations

I want to measure the covariance structure of various asset returns based on varying investment periods. Campbell and Viceira (2005) do this, using known return predictors (i.e. dividend yield, ...
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218 views

Co-integration constraints of coint(X,Z) given coint(X,Y) and coint(Y,Z)?

The Augmented Dickey-Fuller Test can be used to measure how well ranked certain pairs are against others for co-integration. So then say we have a known co-integration between ...
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0answers
109 views

Correlation between idiosyncratic residuals and forward returns

The classic mean-reversion strategy is to calculate an "expected return" (alpha) by computing the raw return for each security and then remove the part which you think is market driven. Statistically ...
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2answers
174 views

Multifractal Model, Generating Sample Paths with Correlations between Assets

I have studied option pricing using Geometric Brownian Motion to generate sample paths. Because of the normal distribution, it is easy to create a covariance matrix and get correlated asset returns. ...
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160 views

Potential pitfalls in the use of correlation

Background: The red line is an index, which goes from 0 to 100, measuring uncertainty in the markets. The dark blue line is a price index, which has a lower bound at 0, and virtually no upper bound. ...
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1answer
1k 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 ...
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71 views

UAC- Unbiased Average Correlation for a Matrix of stocks

Once I have computed a correlation matrix for a portfolio of stocks, how do I calculate the UAC for the correlation matrix? ie, how do I strip out any auto correlation among the names?
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1answer
100 views

tail correlation during crisis

I am seeking a recommendation for an empirical paper on increased correlations of returns during the 2008 financial crisis, or 'tail correlation' during the crisis, if that is different, or whatever ...
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2answers
648 views

Are 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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2answers
196 views

Correlated Wiener processes of different factors

I'm relatively new in this field, so I have a couple of points that I need to clarify. I would like to know how I can estimate the correlation matrix necessary to implement a Cholesky decomposition ...
4
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1answer
235 views

When does the Epps effect start?

Wikipedia defines the Epps effect as follows: In econometrics and time series analysis, the Epps effect, named after T. W. Epps, is the phenomenon that the empirical correlation between the returns ...
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96 views

Applications of distance correlation

This question mentions distance correlation. Where has this concept been applied to financial data and provided new insight? Do you know any examples or references?
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127 views

how to extend lognormal model so that $\sigma$ is correlated to $\mu$?

Consider a log-normal model, $dx / x = \mu dt + \sigma dW$, where $W(t)$ is a Wiener process. Let's say $\mu$ and $\sigma$ change with time, slowly, so we note them by $\mu(t)$ and $\sigma(t)$. ...
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345 views

Average correlation of index/portfolio

We try to analyze the average correlation of a portfolio as it can be found here in section 2 b), the same formula which is also used by the CBOE to calculate implied correlations: $$ \rho_{av(2)} = ...
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216 views

Time-varying correlation via state-space representation and Kalman filter

Let a linear time-varying mode like this one: $y_{t}=\alpha_{t}+\beta_{t}x_{t}+\epsilon_{t}$. You can also suppress the constant term to simplify this example: $y_{t}=\beta_{t}x_{t}+\epsilon_{t}$. ...
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1answer
278 views

Help with understanding a normal distribution/probability question

Could someone please help me translate what this is saying on page P15, section 4.2: http://www.ntuzov.com/Nik_Site/Niks_files/Research/papers/stat_arb/Ahmed_2009.pdf Specifically: When the ...
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1answer
333 views

Non-intuitive correlation between S&P sector indexes and economic indicators

I am trying to understand how changes in economic indicators like Unemployment Rate, Inflation Rate, and Consumer Sentiment affect the portfolio values. For that I want to measure the correlation ...
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1answer
610 views

Counterintuitive time varying Beta with Kalman filter

If you're used to play with R, you'll enjoy the following reproducible code: ...
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261 views

How to deal with zeroes in returns?

Suppose there are two time series that I want to analyze and compare. However, many, or most, of the data are zeroes for some reason. For example, consider a pair of intraday trading returns time ...
6
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740 views

Principle Component Analysis vs. Cholesky Decomposition for MonteCarlo

Let's assume we have a portfolio containing large number (~500) of risk factors. We want to simulate the portfolio dynamics. PCA based simulation would be faster as we can reduce the dimensionality. ...
3
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1answer
2k views

When the Inverse Correlation between the SPX and VIX breaks down

As we all know the S&P and its implied vol, the VIX, generally move in opposite direction. To a large extent, the correlations makes sense. IV is one of the main drivers of the price of options, ...
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179 views

Stress testing covariance

Going one level beyond stressed scenarios, to parameters e.g. for a VaR measure: what are the most common approaches for stressing a covariance/correlation matrix, especially taking portfolio exposure ...
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1answer
374 views

Testing Significance of Correlation

Lets say I have the returns of two stocks(stock1 and stock2). Now without running a regression, I lag one of the variables, calculate the correlation between the two stocks and repeat this process as ...
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185 views

Correlation Sensitivity

Suppose I have 2 stocks $S_{1}$ and $S_{2}$: \begin{align} & dS_{1}=rS_{1}dt+\sigma_{1}S_{1}dB_{1}\\ & dS_{2}=rS_{2}dt+\sigma_{2}S_{2}dB_{2}\\ & dB_{1}dB_{2}=\rho dt \end{align} Then I ...
5
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2answers
392 views

Correlation decay in lognormal distribution

I noticed that if you use two correlated geometric brownian motions, the correlation structure decays in time pretty fast even for really high correlation values. I think that is not replicating ...
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1answer
466 views

Stability of correlations and volatility

I had a discussion recently about the stability of volatilities and correlations. If we take for example stocks and bonds (think of DAX and Bund) then I have seen changing volatilities (something like ...
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1answer
97 views

How can I evaluate how poor a fit a parametric VaR result would be for a given holding?

I'm currently working on an application that, among other things, computes a one-day parametric VaR for security positions. I understand that the parametric method of computing VaR is a poor fit for ...