Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Electrodynamical model of quasi-efficient financial market   The modelling of financial markets presents a problem which is both
theoretically challenging and practically important. The theoretical aspects
concern the issue of market efficiency which may even have political
implications \cite{Cuthbertson}, whilst the practical side of the problem has
clear relevance to portfolio management \cite{Elton} and derivative pricing
\cite{Hull}. Up till now all market models contain "smart money" traders and
"noise" traders whose joint activity constitutes the market \cite{DeLong,Bak}.
On a short time scale this traditional separation does not seem to be
realistic, and is hardly acceptable since all high-frequency market
participants are professional traders and cannot be separated into "smart" and
"noisy". In this paper we present a "microscopic" model with homogenuous
quasi-rational behaviour of traders, aiming to describe short time market
behaviour. To construct the model we use an analogy between "screening" in
quantum electrodynamics and an equilibration process in a market with temporal
mispricing \cite{Ilinski,Dunbar}. As a result, we obtain the time-dependent
distribution function of the returns which is in quantitative agreement with
real market data and obeys the anomalous scaling relations recently reported
for both high-frequency exchange rates \cite{Breymann}, S&P500 \cite{Stanley}
and other stock market indices \cite{Bouchaud,Australia}.

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The categories of this paper are: eess
12
The categories of this paper are: nucl-th
27
The categories of this paper are: comp-gas
33
The categories of this paper are: plasm-ph
30
The categories of this paper are: q-alg
20
The categories of this paper are: acc-phys
32
The categories of this paper are: atom-ph
25
The categories of this paper are: patt-sol
36
The categories of this paper are: cmp-lg
8
The categories of this paper are: hep-ex
14
The categories of this paper are: math-ph
22
The categories of this paper are: chao-dyn
10
The categories of this paper are: q-bio
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The categories of this paper are: dg-ga
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The categories of this paper are: stat
28
The categories of this paper are: alg-geom