Questions tagged [modern-portfolio-theory]
A theoretical framework for analyzing investment portfolios based on their expected return and risk.
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Reference Request: Horse Race for Portfolio Allocation
Probably the most popular horse race study for portfolio strategies is
Optimal versus Naive Diversification: How Inefficient Is the 1/N Portfolio Strategy?, with DeMiguel, L. Garlappi and R. Uppal. ...
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Contribution of an asset's variance to portfolio variance
How can an asset's variance, $\sigma_i^2$, be shown to contribute to portfolio variance, $\sigma_p^2$?
I was thinking of taking the derivative (first order conditions $\frac{\partial L_{\sigma_p^2}(w,\...
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Question about adding new investment A to portfolio B
I've found a ton of sources that mention the classic rule of
"If the Sharpe ratio of the new asset is greater than the Sharpe ratio of the existing portfolio times the correlation of the existing ...
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In portfolio theory, has volatility a logical place as an asset class?
Some years ago, a colleague made the argument that volatility should be thought of as an asset class. That means that taking exposure to implied volatility, in the form of volatility bonds, or long ...
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Black-Litterman: Why should the views be independent of each other?
This question relates to this question.
In the Black-Litterman framework views of inverstors on the market are modelled.
These views have a covariance-matrix $\Omega$.
I always found it quite ...
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R package for portfolio
In the context of modern portfolio theory, one often wishes to minimise
$\mathbf{w}^{\mathrm{{\scriptstyle T}}}\boldsymbol{\Sigma}\mathbf{w}$
subject to $\mathbf{w}^{T}\boldsymbol{\mu}=c_{1}$, $\left\...
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Black-Litterman, how to choose the uncertainty in the views $\Omega$ for smooth transitions from prior to posterior
In Black-Litterman we get a new vector of expected returns of the form:
\begin{align}
\Pi_{BL} = \Pi + \underbrace{\tau \Sigma P^T[P\tau\Sigma P^T+\Omega]^{-1}}_{\text{correction}}[Q-P\Pi]
\end{align}
...
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Derivation of mean-variance portfolio weights as closed-form analytical solution from Lagrangean equations
I am trying to find a closed form solution for the constrained MVO problem below.
$\max_w w'\mu - \frac{\lambda}{2}w'\Sigma w $
s.t. $w'$1 = 1
The Lagrange for the objective is $L(w, \gamma) = w'\mu ...
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How can I find the portfolio with maximum Sharpe Ratio - Using Lagrange Multipliers
In Markowitz' portfolio theory we can construct portfolios with the minimum variance for a given expected return (or vice versa). Across expected risks, this traces out the well-known efficient ...
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Combining modern portfolio theory and Kelly betting?
I'm using modern portfolio theory to compute the frontier of efficient portfolios. I'd like to pick the best one in the spirit of Kelly betting, ie. maximising expected growth.
I'm looking for a ...
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How to apply the "Knapsack Problem" to minimise a portfolio's volatility?
Suppose I have a stock selection universe of 100 stocks.
I have estimated the covariance matrix of this 100 stocks.
I would like to create an equaly-weighted basket of 5 stocks which has the lowest ...
5
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Quasi Random Monte Carlo in m.v. portfolio optimization
Not specifying a correlation matrix for the Monte Carlo Simulation's random returns is equivalent to assuming no correlation or a correlation coefficient of zero, which will seriously and adversely ...
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Mean Variance Investment problem
I attach a part of a paper explaining how the weights of a market portfolio are derived. I do not understand how equation 5 has been derived and, in particular, where the zero beta portfolio's return ...
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Electricity market : how to design an optimal hedging strategy using spot and futures markets for an industrial consumer?
Here is the problem : we should adopt the point of view of an industrial company which purchases electricity as an input in its production line and which wants to achieve the following two goals :
-...
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What is the purest way to get exposure to Jump risk premia, is there a jump swap
So to get exposure to Variance risk premia one could use variance swaps, is there a equivalent security for jumps. Hedging against jump but not diffusion risk could allow one to take targeted exposure ...
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Are heuristic portfolios efficient portfolios?
Markowitz's definition of an efficient portfolio is one that minimizes portfolio risk for a given level of expected return. He therefore calls portfolios along the efficient frontier "frontier ...
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Closed-form analytical solution for the variance of the minimum-variance portfolio?
The portfolio weights vector of the minimum-variance portfolio has a closed-form analytical solution,
$$\boldsymbol{w} = \frac{\boldsymbol{\Sigma}^{-1} \boldsymbol{1} }{\boldsymbol{1}^\top \boldsymbol{...
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Asset Allocation with near zero rates
With central banks pegging interest rates to near zero rates, an argument could be made that the future distribution of interest rates and bond returns are not normally distributed. How has modern ...
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Basic question on Portfolio Theory
I was revising my stuff about portfolio theory and I noticed that every single time, expected return and corresponding variance or covariance are given! (not calculating ourselves). So I'm just ...
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Optimal Portfolios
In modern portfolio theory, one famous problem is the Markowitz mean variance optimal portfolio, defined by solving
$$\underset{\mathbf{w}}{\mbox{min}\,\,}\mathbf{w}^{T}\boldsymbol{\Sigma}\mathbf{w}$$...
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Compute tangency portfolio with asset allocation constraints
I am looking to compute the tangency portfolio of the efficient frontier, but taking into account min_allocations and ...
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Widely accepted methods for coming up with the co-variance matrix of assets?
Question
What are the widely accepted ways for coming up with co-variance matrix of assets
after the Markowitz's modern portfolio theory?
Question explained in more detail
After Modern portfolio ...
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Portfolio Optimization sum of weights constraint with short selling
For mean-variance portfolio optimization with short-selling allowed I have seen 2 ways to specify the portfolio constraint.
In most resources I've seen, such as https://www.coursera.org/learn/...
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Difference between Sharpe Ratio and Information Ratio
I am finding it difficult to understand the difference between the sharpe ratio and the information ratio and the relationship between the two, and cannot find a decent reference that breaks it down ...
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Portfolio with lots of subportfolios
An account manager has $N$ distinct, equally-sized pots of money, which will be used to make $N$ distinct subportfolios, each of which is drawn from a slightly different (but potentially overlapping) ...
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In Mean-Variance Analysis, why not the efficient frontier being pushed to the left near the axis?
I took some classes in portfolio theory, and learnt the Markowitz Mean-Variance Analysis.
If only two risky assets, the efficient frontier would be a hyperbola passing through the two points; now if ...
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Monte Carlo (resampling) in m.v. portfolio optimization
The instability and high sensitivity of optimisation results can be augmented by adding another layer of quantitative methodology in the form of Monte Carlo Simulation. The name Monte Carlo alludes to ...
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Methods for superior estimates of returns in m.v. portfolio optimization
Leaving aside the aspects related to the estimation of the variance component (all the latest techniques to compute a stable covariance matrix of a given set of assets such as simple shrinkage, Ledoit-...
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What value should the risk free monthly return rate be (Sharpe ratio calculation)?
In calculating an annualized Sharpe ratio using monthly returns, what is commonly used as the value for the risk free rate? I am using this formula:
...
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Black-Litterman example
I'm trying to learn Black-Litterman. I feel like I get the overall idea from books like Risk and Asset Allocation by Meucci as well as some of the early papers which develop the model. What I would ...
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Mean-variance portfolio & quadratic programming
I am somewhat confused when it comes to modern portfolio theory, mean-variance portfolio optimization and its quadratic programming formulation.
Issue 1: Formulation of mean-variance portfolio ...
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Using Implied Volatility for Portfolio Optimization
Hello I am interested in portfolio optimization . Previously I when I have done portfolio optimization I would take the historical returns of a stock and use them to perform a mean variance ...
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Why the weight vector of 'global minimum variance' the 'eigenvector' with the minimum eigenvalue?
Question
Why is it the case that the weight vector of the global minimum variance portfolio the eigenvector of the covariance matrix with the smallest eigenvalue?
Question with more details
I ...
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Fama French & Solving for Alpha
This is a question about comparing results from the Fama french 3 factor model.
I have not physically done this, but let's assume a Fama French 3 factor regression was performed for Coca-Cola (KO) ...
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Capital Allocation for Portfolio of Multi-Strategy and Multi-Instrument
I would like to know if there is a way (or theory) to manage a multi-strategy, multi-instruments portfolio that would calculate the optimal weight to allocate capital for each combination of strategy ...
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Why is the CAPM securities market line straight?
Let $\gamma$ be the expected return, in terms of its exponential growth rate, of the market asset. If we set $\gamma=\mu-\sigma^2/2$ as explained by the Doléans-Dade exponential, then the expected ...
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Do managers information ratios exhibit autocorrelation? Ie. are they stable over time?
I'm reading through Active Portfolio Management, and I can't get my head around Information Ratio's real world applicability.
In table 5.6 it lists some empirical infomation ratios:
However, there is ...
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What on earth is an Alpha Model in the quantative investment process?
I am confused with the useage of the concept "Alpha Model" in quantative investment. According to Qian, Hua & Sorensen (2007), the first thing in the toolbox of quantative investment process is "...
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CAPM - market portfolio vs real portfolio
I'm trying to understand the relation (if there is any) between the market portfolio, as described by the CAPM theory, and a real portfolio (just like the one I plotted in the image below).
More ...
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Recommended Literature for creating Factor Mimicking Portfolios
Is there a textbook that contains the basics for creating Factor Mimicking Portfolios? Although there is a lot of peer-reviewed literature on this, I cannot find textbooks on Asset Pricing that ...
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How to see if a set of asset returns corresponds to a known correlation matrix?
Let's say I have an arbitrary set of $n$ period returns for $k$ assets, and a given $k \times k$ correlation matrix (of asset returns), which is known a priori.
Does it makes sense, or is it even ...
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How to derive the CAPM from maximizing the Sharpe ratio?
I know how to derive at the CAPM from a microeconomic foundation. In a recent University course I stumbled over a slide that derived the CAPM solely from the Sharpe ratio:
I cant come up with that ...
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Origin of the term Modern Portfolio Theory
In his times, Markowitz did not claim his ideas were "modern".
Not even the expression "Portfolio Theory" is ever used in his seminal paper and subsequent book, while he speaks instead of "Theory of ...
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Mixing Portfolio Strategies
Given a set of $N$ assets, the amount of strategies proposed in literature to diversify the investors wealth in order to find the 'optimal' portfolio is overwhelming. However, for example DeMiguel et ...
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Definition of sharpe ratio maximising and variance minimising portfolios
In this paper, http://papers.ssrn.com/sol3/papers.cfm?abstract_id=2226985, in the derivation of the mean variance efficient portfolio using lagrangians in the appendix, on page 29, the two portfolios ...
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Portfolio Optimization with Monte Carlo Simulation - How to do it with Excel?
If I have three asset classes and their historical weekly returns for five years, how can I construct a minimum variance portfolio and an efficient frontier plot with Excel? To do that do I have to ...
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How are the Hamilton–Jacobi–Bellman equations used to solve optimal control problems?
I would like to learn more on how optimal control problems are solved for financial applications.
The approach seems to have a lot of interesting applications such as
optimal consumption
choosing ...
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Evaluating estimate of covariance matrix
I am testing out different methods / shrinkages to estimate a covariance matrix and I am wondering what is the best method of comparing the estimated covariance matrix to the true covariance matrix (...
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Two approaches to optimizing quadratic utility
My understanding of the traditional Markowitz portfolio optimization process is as follows:
Let’s say I have data from year 1 to year 10. At the end of year 10 (having information about year 10), I ...
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Annualization of coskewness and cokurtosis
I am constructing a mean-variance-skewness-kurtosis portfolio based on monthly data with a holding period of one year. Meucci describes how to annualize higher order moments in general, but not how to ...