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bio website researchgate.net/profile/…
location Vienna, Austria
age 33
visits member for 2 years, 2 months
seen 14 hours ago

Risk Manager at an Asset Management Company

External Lecturer at Vienna University of Technology


Jun
30
comment Plot Evolution of portfolio weights over time in R
I think this is off-topic because in short you ask how to plot multvariate time series - right? Look at the xts package cran.r-project.org/web/packages/xts/index.html and get to know time formats in R.
Jun
30
comment How do I prove that $\lim_{K\searrow0}\frac{P(K,T)}{K} = \mathbb P(S_T=0)$?
So we have $\lim_{K\rightarrow 0} \frac{1}{K} \int_0^K x dF(x) = 0$ right? A reference would be what they call the second fundamental theorem of calculus as described here. The main point is that the limit $K\rightarrow 0$ leads to taking the derivative and we can take the function inside the integral and evaluate it at $K$ ... Sorry but we can not let $K$ tend to zero, use this as an agrument for the theorem and then evaluate at $K=0$. This is still not 100% rigorous, in my mind ...
Jun
29
comment Non-negative matrix factorization for factor analysis of stocks
Thanks for your answer but my question is about the concept nnmf as described and not about factor models in general.
Jun
27
comment How do I prove that $\lim_{K\searrow0}\frac{P(K,T)}{K} = \mathbb P(S_T=0)$?
yes ... I thought so too. I wonder how this theorem is called and what the conditions are ...
Jun
27
comment How do I prove that $\lim_{K\searrow0}\frac{P(K,T)}{K} = \mathbb P(S_T=0)$?
Which model do you consider? Black Scholes or something different?
Jun
27
comment How do I prove that $\lim_{K\searrow0}\frac{P(K,T)}{K} = \mathbb P(S_T=0)$?
Why is the last step valid? Could you mention a rule from calculus?
Jun
26
comment Modelling with negative interest rates
This is a long and interesting answer- would you like to use latex to make it more readable? Thanks.
Jun
23
answered questions on VAR manipulation
Jun
23
comment Infinite autocorrelation - Unit root?
Please clarify the titel of your question. What does "infinite" autocorrelation mean? ;)
Jun
21
awarded  Yearling
Jun
20
accepted Controling ex-post volatility by ex-ante limits
Jun
20
comment Controling ex-post volatility by ex-ante limits
@John I have done the above simulations with Gaussian returns and additionally with t-distributed retunrs in order to have fatter tails. The ex-ante limit in simulations seems to work. In the setting where I have to obey some ex-post limit .. what else could I do? I observe past variance and then ex-ante I try to control the near future. Any other idea? Thanks!
Jun
20
answered Hedging a Long Equity Swap by Shorting the Stock
Jun
18
comment Beta of FTSE100 stocks against benchmark index FTSE100
It is not true that small beta means low vol. There is still idiosyncratic risk in the stocks.
Jun
16
answered Basis Risk for Futures/Options
Jun
16
comment Short-term directional trading
I agree that this questions is not clear. I voted to close it if it is not improved.
Jun
13
answered Controling ex-post volatility by ex-ante limits
Jun
13
revised Controling ex-post volatility by ex-ante limits
added 4 characters in body
Jun
12
asked Controling ex-post volatility by ex-ante limits
Jun
12
comment Optimal trading strategy in toy world of simple Hidden Markov model with Gaussians
Note that if $\mu_0 = \mu_1$ then you get zero autocorrelation of returns - which is often the case (look here in Rogers and Zhang (2.2)