88 research outputs found
Hedging Conditional Value at Risk with Options
We present a method of hedging Conditional Value at Risk of a position in
stock using put options. The result leads to a linear programming problem that
can be solved to optimise risk hedging.Comment: 10 pages, 0 figure
Geometric proof for normally hyperbolic invariant manifolds
We present a new proof of the existence of normally hyperbolic manifolds and
their whiskers for maps. Our result is not perturbative. Based on the bounds on
the map and its derivative, we establish the existence of the manifold within a
given neighbourhood. Our proof follows from a graph transform type method and
is performed in the state space of the system. We do not require the map to be
invertible. From our method follows also the smoothness of the established
manifolds, which depends on the smoothness of the map, as well as rate
conditions, which follow from bounds on the derivative of the map. Our method
is tailor made for rigorous, interval arithmetic based, computer assisted
validation of the needed assumptions.Comment: 64 pages, 4 figure
Real options - realistic valuation
In valuation of real options, a widely accepted assumption is that the underlying real asset is perfectly correlated with a financial one. As a result, valuation techniques from the financial world can be used. Since this assumption is in general unrealistic and may lead to substantial mispricing, even if the correlation is very high but not perfect, we argue that a different approach is more adequate. It is based on a simple principle of invariance of the market price of risk computed for certain portfolios involving the underlying asset and the options. This is illustrated on a simple model where we can clearly see the relations between the prices obtained by various methods
Predicting exchange rates via a futures market
Predicting future spot exchange rates has always been useful for companies trading internationally. Now finding future exchange rates is essential for countries that are to join common currency zones (Eurosystem) and need to set reference rates for the ERM II. This paper presents a model that attempts to determine exchange rates and, unlike others, is based on an analysis of the futures market. The model is based on the assumption that the futures market is dominated by two categories of traders: arbitrageurs and fundamental traders. The divergence of the futures rate from its theoretical value is gauged and then considered to be an indication of the direction and strength of the two forces in the market. The arbitrageurs' influence is filtered out and thus the model outputs the rate based on the fundamental traders' expectations
Implications of contrarian and one-sided strategies for the fair-coin game
We derive some results on contrarian and one-sided strategies by Skeptic for
the fair-coin game in the framework of the game-theoretic probability of Shafer
and Vovk \cite{sv}. In particular, concerning the rate of convergence of the
strong law of large numbers (SLLN), we prove that Skeptic can force that the
convergence has to be slower than or equal to . This is achieved
by a very simple contrarian strategy of Skeptic. This type of result, bounding
the rate of convergence from below, contrasts with more standard results of
bounding the rate of SLLN from above by using momentum strategies. We also
derive a corresponding one-sided result
Company valuation : value, structure, risk
This book, for a few different reasons, was focused on the DCF method, the
main of the reasons being that the DCF method captures best the value of prof-
itable, economically sound companies â it works for all firms which have real
expertise. The main purpose of this book was to explain the inner workings of
the DCF method, especially the variant in which capital structure constantly af-
fects cost of equity, as it does in reality.
The focus then was on the valuation model which integrates the three com-
ponents that elsewhere are often treated separately: cash flows, the cost of capi-
tal and the discounting process itself. The book revolved around these three is-
sues. For example, it is commonly known that if the value of equity changes,
the capital structure changes too. At the same time the change may affect the
cost of capital, which in turn will influence the value of equity itself. The re-
cursive approach to company valuation that was presented in the book relied
on solving such logical loops that appeared both at each time period and along
time periods. Performing the company valuation is such a way is much more
complicated than assuming no links between for example the value of equity
and the cost of capital, but leads to a much more reliable and methodically f law-
less valuation
Geometric Proof of Strong Stable/Unstable Manifolds, with Application to the Restricted Three Body Problem
We present a method for establishing invariant manifolds for saddle--center
fixed points. The method is based on cone conditions, suitably formulated to
allow for application in computer assisted proofs, and does not require
rigorous integration of the vector field in order to prove the existence of the
invariant manifolds. We apply our method to the restricted three body problem
and show that for a given choice of the mass parameter, there exists a
homoclinic orbit to one of the libration points.Comment: 34 pages, 6 figure
A Stochastic Process Approach of the Drake Equation Parameters
The number N of detectable (i.e. communicating) extraterrestrial
civilizations in the Milky Way galaxy is usually done by using the Drake
equation. This equation was established in 1961 by Frank Drake and was the
first step to quantifying the SETI field. Practically, this equation is rather
a simple algebraic expression and its simplistic nature leaves it open to
frequent re-expression An additional problem of the Drake equation is the
time-independence of its terms, which for example excludes the effects of the
physico-chemical history of the galaxy. Recently, it has been demonstrated that
the main shortcoming of the Drake equation is its lack of temporal structure,
i.e., it fails to take into account various evolutionary processes. In
particular, the Drake equation doesn't provides any error estimation about the
measured quantity. Here, we propose a first treatment of these evolutionary
aspects by constructing a simple stochastic process which will be able to
provide both a temporal structure to the Drake equation (i.e. introduce time in
the Drake formula in order to obtain something like N(t)) and a first standard
error measure.Comment: 22 pages, 0 figures, 1 table, accepted for publication in the
International Journal of Astrobiolog
Characterising blenders via covering relations and cone conditions
A blender is an invariant hyperbolic set of a diffeomorphism with the
property that its stable or unstable manifold has a dimension larger than
expected from the underlying hyperbolic splitting. We present a
characterisation of a blender based on the correct topological alignment of
sets in combination with the propagation of cones. It is applicable to
multidimensional blenders in ambient phase spaces of any dimension. The
required conditions can be verified by checking properties of a single iterate
of the diffeomorphism, which is achieved by positioning the required sets in
such a way that they form a suitable sequence of coverings. This setup is
flexible and allows for a rigorous, interval arithmetic based, computer
assisted validation. As a demonstration, we apply our approach to obtain a
computer-assisted proof of the existence of a blender in a three-dimensional
H{\'e}non-like family of diffeomorphisms over a considerable range of the
relevant parameter.Comment: 29 pages, 15 figure
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