Questions tagged [coherent-risk-measure]

The tag has no usage guidance.

Filter by
Sorted by
Tagged with
0
votes
1answer
63 views

Chorent risk measure with superaddative

In some definition of chorent risk measure Superadditive is one of the properties I don't understand Why? With subadditivity and homogeneous CvaR is convex, but if we assume another definition for ...
22
votes
3answers
9k views

What is a “coherent” risk measure?

What is a coherent risk measure, and why do we care? Can you give a simple example of a coherent risk measure as opposed to a non-coherent one, and the problems that a coherent measure addresses in ...
0
votes
0answers
38 views

Choquet integral risk measure

I have one question that cannot fully understand why. What is the definition of the Choquet integral risk measure?
4
votes
1answer
77 views

Bregman Mean of a Distribution

In a paper (link), author writes, given that $\gamma:R\rightarrow \bar{R}$ is a convex function, $dom_{\gamma}:=\{x\in R:\gamma(x)<+\infty\}$ is a non-empty open set and $\gamma$ a closed proper ...
12
votes
2answers
1k views

Examples of Spectral Risk Measures

Let's take the usual definition of a spectral risk measure. If we look at the integral we see that spectral risk measures have the property that the risk measure of a random variable $X$ can be ...
1
vote
0answers
44 views

Risk Measure-identication

Let X be a variable with existing moment generating function $M_x(z)=E[e^{zX}]$. Define the following risk measure: $\rho_{\alpha}(X)=inf_{z>0}(z^{-1}ln(\frac{M_x(z)}{1-\alpha}))$ Does anyone know ...
2
votes
0answers
38 views

Example of Coherent Risk measure with Compact Representation

Every coherent risk measure $\rho$ can be represented as $$ \rho(X)\triangleq \sup_{Q \in \mathcal{Q}} \mathbb{E}\left[ -X \right], $$ for a set of probability measures $\mathcal{Q}$ defined on the ...
0
votes
0answers
105 views

What's the advantages of $EVaR$ over $CVaR$?

$CVaR$, which is short for Conditional Value-at-Risk, has long been accepted by both academe and practice as a good coherent risk measure. Entropic value-at-risk ($EVaR$) is a comparative new coherent ...
1
vote
1answer
269 views

Calculating Expected Shortfall of combined portfolios

So I am reading lecture notes here: https://courses.edx.org/c4x/DelftX/TW3421x/asset/Week3_var_3_slides.pdf The example is this: We have two independent portfolios of bonds. They both have a ...
1
vote
1answer
1k views

Is Value-at-Risk translation invariant?

Let: $X=V_1-V_0R_0$ where $R_0$ is the interest rate. Then, is it so that this risk measure is Translation Invariant as: $\textit{VaR}_{\alpha}(X)=\textit{VaR}_{\alpha}(V_1-V_0R_0)=V_0+\textit{VaR}_{\...
5
votes
2answers
253 views

How to calculate the distortion function for CVaR?

Can anyone give me some hints as to how to prove that $$g(x) = \begin{cases} \frac{x}{1-\alpha}, &0 \leq x \leq 1-\alpha\\ 1 , &1-\alpha \leq x \leq 1 \end{cases}$$ ...
15
votes
3answers
6k views

Gamma vs. Volatility Risk

Original Question: What is the link between Gamma and the Volatility Risk? It leads me to ask: - What is the Volatility Risk definition and what are the good practices to measure it? Thinking about ...
0
votes
1answer
655 views

Convex risk measure and a coherent risk measure?

A coherent risk measure is: $\rho(\lambda X_1+(1-\lambda X_2))$ How can it be shown that everey convex risk measure is indeed a coherent risk measure? I assume that it is enough to show that a ...
0
votes
1answer
107 views

Good book about replicating portfolios

I want to know if anybody can suggest me a good textbook which explains in detail and in an understandable way how to create replicating portfolios of financial instruments like options "cash or ...
3
votes
1answer
497 views

Is volatility really a coherent risk measure?

Why people say that volatility is a coherent risk measure? I don't see it clearly because what happen if the two assets are correlated positively? subadditivity would not be preserved. That ...
2
votes
1answer
1k views

Elicitability of risk measures

I read that CVaR (Conditional Value-at-Risk, also Expected Shortfall), satisfies coherence, but not Elicitability. On the other hand, VaR satisfies Elicitability, but not coherence. What is ...
1
vote
2answers
83 views

different amount of information on return correlations from shorter and longer periods?

I want to calculate annual excess returns on portfolios using monthly (total) returns for a CAPM (for the assets in the portfolio as well as for the benchmark), in order to have more information on ...
2
votes
1answer
940 views

annual excess returns from CAPM on monthly total returns

I want to calculate annual excess returns on portfolios using monthly returns for a CAPM (for the assets in the portfolio as well as for the benchmark), in order to have more information on the ...
1
vote
1answer
139 views

right benchmark for an incompletely diversified international portfolio (for a CAPM): MSCI World or MSCI ACWI IMI?

I want to calculate annual excess returns on portfolios using monthly returns for a CAPM (for the assets in the portfolio as well as for the benchmark), in order to have more information on the ...
2
votes
1answer
5k views

how to chain monthly excess returns into annual?

I want to calculate annual excess returns on portfolios using monthly returns for a CAPM (for the assets in the portfolio as well as for the benchmark), in order to have more information on the ...
2
votes
0answers
139 views

Portfolio insurance with a coherent risk measure (CVaR)

I would like to analysis of portfolio insurance under a coherent risk-measure method (CVaR), How can I achieve that? Is there a way to turn the problem into a linear programming problem? or to ...
11
votes
2answers
12k views

What is the meaning of subadditivity in a risk measure?

The subadditivity reads: $\rho(X_1+X_2) \leq \rho(X_1) + \rho(X_2)$ What is the meaning of this condition? I can vaguely accept that one should diversify the investment portfolio. Or, I can ...
7
votes
2answers
710 views

Does a coherent risk measure satisfy the four axioms of von Neumann–Morgenstern?

What is the relationship between the axioms of Artzner et al (1999) for coherent risk measures and the axioms of von Neumann-Morgenstern (1944) for the expected utility theory?
17
votes
3answers
4k views

Is Conditional Value-at-Risk (CVaR) coherent?

When the risk is defined by a discrete random variable, is CVaR a coherent risk measure? I stick to the following definition of CVaR: $$ CVaR_\alpha(R) = \min_v \quad \left\{ v + \frac{1}{1-\alpha} \...
8
votes
1answer
449 views

Which is a more appropriate choice of risk measurement in a utility function, CVaR or VaR?

What is the consensus on which risk measure to use in measuring portfolio risk? I am researching what is the best risk measure to use in a portfolio construction process for a long/short option-free ...
8
votes
1answer
1k views

Value at Risk backtesting (kupiec)

I m doing my research on estimating Value at risk using different assumptions on volatility and then compare my results based on backtesting. I obtained results and just on question based on my ...