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11.
Dieter Hoffmann 《Physics in Perspective (PIP)》2000,2(4):426-445
A guided tour of significant sides pertaining to the history of physics is conducted around the area of the Technische Universit?t
and the Physikalisch-Technische Reichsanstalt in Berlin-Charlottenburg, of the Institutes of the former Kaiser Wilhelm Society
in Berlin-Dahlem, as well as to some points of interest in the area of Potsdam. 相似文献
12.
M. Beben A. Orłowski 《The European Physical Journal B - Condensed Matter and Complex Systems》2001,20(4):527-530
Long-time correlations in both well-developed and emerging market indexes are studied. The Hurst exponent as well as detrended
fluctuations analysis (DFA) are used as technical tools. Some features that seem to be specific for developing markets are
discovered and briefly discussed.
Received 17 October 2000 相似文献
13.
Bahri Sahin Huseyin Yilmaz Yasin Ust Ali Fuat Guneri Bahadır Gulsun 《European Journal of Operational Research》2009
One of the important parameters in the determination of optimal transportation system is economy. Therefore, a realistic method based on the technical, economical and operational parameters of various transportation modes, namely, road, railway, and sea routes is required in the analysis of costs. This method will take into consideration the probable price escalations during the lifetime of a certain transportation system. The cost of a unit of cargo or passenger per route length should be considered since it is an indicator of economics. In this paper, an approach for transportation cost analysis based on the economic analysis of the alternative modes of cargo or passenger transportation, is presented. 相似文献
14.
This paper briefly reviews the existing methods of capacity utilization in nonparametric framework from economic perspectives, and then suggests an alternative in the light of limitations therein. In the spirit of work by Coelli et al. [Coelli, T.J., Grifell-Tatje, E., Perelman, S., 2002. Capacity utilisation and profitability: A decomposition of short run profit efficiency. International Journal of Production Economics 79, 261–278], we propose two methods, radial and non-radial, to decompose the input-based physical (technological) capacity utilization into various meaningful components viz., technical inefficiency, ray economic capacity utilization and optimal capacity idleness. A case study of Indian banking industry is taken as an example to illustrate the potential application of these two methods of decomposition. Our two broad empirical findings are that first, competition created after financial sector reforms generates high efficiency growth, and reduces excess capacity; second, the cost gap of the short-run cost from the actual cost is higher for the nationalized banks over the private banks indicating that the former banks, though old, do not reflect their learning experience in their cost minimizing behavior. 相似文献
15.
L.Y. Fong K.Y. Szeto 《The European Physical Journal B - Condensed Matter and Complex Systems》2001,20(4):569-572
Data mining is performed using genetic algorithm on artificially generated time series data with short memory. The extraction
of rules from a training set and the subsequent testing of these rules provide a basis for the predictions on the test set.
The artificial time series are generated using the inverse whitening transformation, and the correlation function has an exponential
form with given time constant indicative of short memory. A vector quantization technique is employed to classify the daily
rate of return of this artificial time series into four categories. A simple genetic algorithm based on a fixed format of
rules is introduced to do the forecasting. Comparing to the benchmark tests with random walk and random guess, genetic algorithms
yield substantially better prediction rates, between 50% to 60%. This is an improvement compared with the 47% for random walk
prediction and 25% for random guessing method.
Received 29 August 2000 相似文献
16.
S. Galluccio 《The European Physical Journal B - Condensed Matter and Complex Systems》2001,20(4):595-600
We consider the problem of option pricing when the underlying asset follows a general semimartingale process. After reviewing
the foundations of arbitrage pricing theory for semimartingales and the link with Lévy processes, we introduce a general method
to price options in this framework based on Fourier and Wavelet analysis.
Received 4 September 2000 相似文献
17.
Universal features in stock markets and their derivative markets are studied by means of probability distributions in internal rates of return on buy and sell transaction pairs. Unlike the stylized facts in normalized log returns, the probability distributions for such single asset encounters incorporate the time factor by means of the internal rate of return, defined as the continuous compound interest. Resulting stylized facts are shown in the probability distributions derived from the daily series of TOPIX, S & P 500 and FTSE 100 index close values. The application of the above analysis to minute-tick data of NIKKEI 225 and its futures market, respectively, reveals an interesting difference in the behavior of the two probability distributions, in case a threshold on the minimal duration of the long position is imposed. It is therefore suggested that the probability distributions of the internal rates of return could be used for causality mining between the underlying and derivative stock markets. The highly specific discrete spectrum, which results from noise trader strategies as opposed to the smooth distributions observed for fundamentalist strategies in single encounter transactions may be useful in deducing the type of investment strategy from trading revenues of small portfolio investors. 相似文献
18.
A. P. Nawroth J. Peinke 《The European Physical Journal B - Condensed Matter and Complex Systems》2006,50(1-2):147-151
A new approach is presented to describe the change in the statistics of the log return distribution of financial data as a
function of the timescale. To this purpose a measure is introduced, which quantifies the distance of a considered distribution
to a reference distribution. The existence of a small timescale regime is demonstrated, which exhibits different properties
compared to the normal timescale regime for timescales larger than one minute. This regime seems to be universal for individual
stocks. It is shown that the existence of this small timescale regime is not dependent on the special choice of the distance
measure or the reference distribution. These findings have important implications for risk analysis, in particular for the
probability of extreme events. 相似文献
19.
E. Bompard Y. C. Ma E. Ragazzi 《The European Physical Journal B - Condensed Matter and Complex Systems》2006,50(1-2):153-160
Competition has been introduced in the electricity markets with
the goal of reducing prices and improving efficiency. The basic idea which
stays behind this choice is that, in competitive markets, a greater quantity
of the good is exchanged at a lower price, leading to higher
market efficiency.
Electricity markets are pretty different from other commodities
mainly due to the physical constraints related to the network structure that
may impact the market performance. The network structure of the system on
which the economic transactions need to be undertaken poses strict physical
and operational constraints.
Strategic interactions among producers that game the market with the
objective of maximizing their producer surplus must be taken into account
when modeling competitive electricity markets. The physical constraints,
specific of the electricity markets, provide additional opportunity of
gaming to the market players. Game theory provides a tool to model such a
context. This paper discussed the application of game theory to physical constrained
electricity markets with the goal of providing tools for assessing the market
performance and pinpointing the critical network constraints that may impact
the market efficiency. The basic models of game theory specifically designed
to represent the electricity markets will be presented. IEEE30 bus test
system of the constrained electricity market will be discussed to show the
network impacts on the market performances in presence of strategic bidding
behavior of the producers. 相似文献
20.
T. Kaizoji 《The European Physical Journal B - Condensed Matter and Complex Systems》2006,50(1-2):123-127
In this paper, we quantitatively investigate the properties of a statistical ensemble of stock prices. We focus attention
on the relative price defined as X(t) = S(t)/S(0), where S(0), is the stock price for an onset time of the bubble. We selected
approximately 3200 stocks traded on the Japanese Stock Exchange, and formed a statistical ensemble of daily relative prices
for each trading day in the 3-year period from January 4, 1999 to December 28, 2001, corresponding to the period in which
internet Bubble formed and crashed in the Japanese stock market.
We found that the upper tail of the complementary cumulative distribution function of the ensemble of the relative prices
in the high value of the price is well described by a power-law distribution, P(S>x) ∼x-α , with an exponent that moves over time. Furthermore we found that as the power-law exponents α approached two, the bubble burst. It is reasonable to suppose that it indicates that internet bubble is about to burst. 相似文献