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836 views

Approximately what proportion of a stock’s volatility is explained by market movement?

Assume we decompose the daily (log) returns of a stock as beta times market movement plus an idiosyncratic part. If this is done ex-ante, what proportion of the variance is explained by the market ...
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Which approach to estimating fundamental factor models is better, cross-sectional (unobservable) factors or time-series (observable) factors?

There are many approaches to estimating fundamental factor equity models. I would like to focus on two traditional methods: The time-series regression approach of Fama and French. Factors are ...
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is beta of a portfolio always meaningful?

Consider the following strategies: a stat arb strategy with no overnight exposure, but significant market exposure intraday. a market timing model which is always long or short the market. etc is ...
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Why is the first principal component a proxy for the market portfolio, and what other proxies exist?

Let's say that I have a universe of stocks from a certain sector. I want to compute the market portfolio of this sector. Beta is the covariance between each stock and the market. But how do you ...
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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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Beta vs. Implied Volatility statistical arbitrage using options

Let two underlyings, $S_{1}$ and $S_{2}$, are correlated and $\beta$ is the slope of their returns linear regression, that is, it says how much $S_{1}$ co-variates with $S_{2}$ variance. For instance,...
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How to account for jumps in intraday data when calculating beta?

I am calculating betas on intraday trade data at 15-minute intervals. For simplicity sake, let's assume I am modeling $$Y = \beta * X + c$$ where $Y$ is the return of XLF ...
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How well does CAPM beta track the risk of a particular market relative to world markets?

Can the CAPM beta of emerging markets be less than the beta of the developed markets? As part of my research, I run regressions using market indices. I estimate the beta using a regression of MSCI ...
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How does Kalman filtering of beta in pairs trading model work in R?

Could anyone show how this could be done in R? The dlm package seems to be a good start, but I can't really find any good examples to learn from. Currently I have ...
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How google finance calculates beta of a stock

How google finance calculates beta of a stock - What is the proxy for the market? - What is the time period it uses for regression?
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Is Least Median Squares (LMS) regression commonly used in Finance?

Least Median Squares is often argued to give more stable results than does OLS. Whereas in OLS one minimises the mean of squared residuals, in LMS, one instead minimises the median of squared ...
447 views

How to interpret beta meaningfully?

Although this is probably a basic question, this is probably also the right forum to post it in :) I thought I understood beta, but know I am really confused... The beta between my portfolio (weekly ...
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Given two portfolios with identical correlation matrices, which one will have a better risk/reward ratio?

I have one portfolio with high beta stocks, and one with low beta stocks. Is it better to have higher expected return with high volatility, or medium expected return with medium volatility? (All from ...
277 views

Beta Constrained Markowitz Minimum Variance Portfolio - Closed Form Solution

This question is related to recent rule changes in the Quantopian Open. I am trying to figure out a closed form solution to a beta constrained minimum variance portfolio problem but it doesn't seem ...
107 views

Fama French model-small market beta (weird)

I am analyzing if good governance portfolios outperform bad governance portfolios. After dividing firms with good governance into one pf and bad ones into another for European companies I tried to run ...
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Are smart beta and risk parity the same?

So from what I have been reading online, smart beta ETFs aim to use a different type of weighting (instead of by market cap as traditional ETFs like SPY do to track an index) to achieve positive ...
1k views

Proof of Hamada's Formula (Relationship between levered and unlevered beta)

Hamada's formula is presented as follows: $$\beta_{U}=\left[\frac{1}{1+\frac{D}{E}(1-\tau)}\right]\beta_{L},$$ where $\beta_{U}$ and $\beta_{L}$ are the unlevered and levered beta's of a firm ...
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What is the point/benefit of using a dollar-neutral strategy in addition to a Beta-neutral strategy? What exactly does a dollar-neutral strategy buy the investor? What's useful about balancing long ...
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How to get Correlation using Options data?

I can calculate the "Implied Beta" using implied volatility for the option stock, and implied volatility for the market (VIX). Is there any way to calculate also the correlation without performing a ...
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How to get Multivariate Betas from an Estimated EWMA co variance Matrix?

I have a portfolio of 4 assets. I also have returns for 3 indices. I want to get the multivariate betas for these 4 assets-based on these assets. I only have the 7 x 7 covariance matrix estimated by a ...
451 views

Beta arbitrage in CAPM

i'm following the "Computational Investing 1" course at Coursera.org, I was affascinated by the Beta arbitrage of CAPM Video: https://class.coursera.org/compinvesting1-002/lecture/view?lecture_id=119 ...
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Beta and the Assumption of IID Returns

For two stocks that are independent and identically distributed (iid), do they have the same beta? Does the number of data points matter?
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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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How to estimate the beta of corporations?

Are there certain strategies and general rules on how to estimate the beta of certain companies? How do I instantly know that it's a beta < 1 or a beta >> 1 corporation? Any helpful ratios that ...
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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 ...