47,095 research outputs found
On Feedback Control in Kelly Betting: An Approximation Approach
In this paper, we consider a simple discrete-time optimal betting problem
using the celebrated Kelly criterion, which calls for maximization of the
expected logarithmic growth of wealth. While the classical Kelly betting
problem can be solved via standard concave programming technique, an
alternative but attractive approach is to invoke a Taylor-based approximation,
which recasts the problem into quadratic programming and obtain the closed-form
approximate solution. The focal point of this paper is to fill some voids in
the existing results by providing some interesting properties when such an
approximate solution is used. Specifically, the best achievable betting
performance, positivity of expected cumulative gain or loss and its associated
variance, expected growth property, variance of logarithmic growth, and results
related to the so-called survivability (no bankruptcy) are provided.Comment: To appear in the proceedings of the 2020 IEEE Conference on Control
Technology and Applications (CCTA
The Pentaquarks in the Linear Molecular Heptaquark Model
In this talk, multiquarks are studied microscopically in a standard quark
model. In pure ground-state pentaquarks the short-range interaction is computed
and it is shown to be repulsive. An additional quark-antiquark pair is then
considered, and this is suggested to produce linear molecular system, with a
narrow decay width. The quarks assemble in three hadronic clusters, and the
central hadron provides stability. The possible crypto-heptaquark hadrons with
exotic pentaquark flavours, with strange, charmed and bottomed quarks, are
predicted.Comment: 6 pages, 3 tables, talk presented as the Eighth Workshop on
Non-Perturbative Quantum Chromodynamics 7-11 June 2004, Paris, proceedings
edited by B. Muller, Chung-I Tan and Y. Gabellin
On Inefficiency of Markowitz-Style Investment Strategies When Drawdown is Important
The focal point of this paper is the issue of "drawdown" which arises in
recursive betting scenarios and related applications in the stock market.
Roughly speaking, drawdown is understood to mean drops in wealth over time from
peaks to subsequent lows. Motivated by the fact that this issue is of paramount
concern to conservative investors, we dispense with the classical variance as
the risk metric and work with drawdown and mean return as the risk-reward pair.
In this setting, the main results in this paper address the so-called
"efficiency" of linear time-invariant (LTI) investment feedback strategies
which correspond to Markowitz-style schemes in the finance literature. Our
analysis begins with the following principle which is widely used in finance:
Given two investment opportunities, if one of them has higher risk and lower
return, it will be deemed to be inefficient or strictly dominated and generally
rejected in the marketplace. In this framework, with risk-reward pair as
described above, our main result is that classical Markowitz-style strategies
are inefficient. To establish this, we use a new investment strategy which
involves a time-varying linear feedback block K(k), called the drawdown
modulator. Using this instead of the original LTI feedback block K in the
Markowitz scheme, the desired domination is obtained. As a bonus, it is also
seen that the modulator assures a worst-case level of drawdown protection with
probability one.Comment: This paper has been published in Proceedings of 56th IEEE Conference
on Decision and Control (CDC) 201
Modelling the Effect of Treatment and Behavioral Change in HIV Transmission Dynamics
25 pages, 1 article*Modelling the Effect of Treatment and Behavioral Change in HIV Transmission Dynamics* (Hsieh, Ying-Hen; Velasco-Hernandez, Jorge X.) 25 page
Propagation of Memory Parameter from Durations to Counts
We establish sufficient conditions on durations that are stationary with
finite variance and memory parameter to ensure that the
corresponding counting process satisfies () as , with the same memory parameter that was assumed for the durations. Thus, these conditions ensure that
the memory in durations propagates to the same memory parameter in counts and
therefore in realized volatility. We then show that any utoregressive
Conditional Duration ACD(1,1) model with a sufficient number of finite moments
yields short memory in counts, while any Long Memory Stochastic Duration model
with and all finite moments yields long memory in counts, with the same
Entanglement preserving local thermalization
We investigate whether entanglement can survive the thermalization of
subsystems. We present two equivalent formulations of this problem: (1) Can two
isolated agents, accessing only pre-shared randomness, locally thermalize
arbitrary input states while maintaining some entanglement? (2) Can
thermalization with local heat baths, which may be classically correlated but
do not exchange information, locally thermalize arbitrary input states while
maintaining some entanglement? We answer these questions in the positive at
every nonzero temperature and provide bounds on the amount of preserved
entanglement. We provide explicit protocols and discuss their thermodynamic
interpretation: we suggest that the underlying mechanism is a speed-up of the
subsystem thermalization process. We also present extensions to multipartite
systems. Our findings show that entanglement can survive locally performed
thermalization processes accessing only classical correlations as a resource.
They also suggest a broader study of the channel's ability to preserve
resources and of the compatibility between global and local dynamics.Comment: 6+7 pages, 1 figure, closed to the published versio
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