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Abstract  

This study compares the citations characteristics of researchers in engineering disciplines with other major scientific disciplines, and investigates variations in citing patterns within subdisciplines in the field of engineering. Utilizing citations statistics including Hirsch’s (Proc Natl Acad Sci USA 102(46):16569–16572, <cite>2005</cite>) h-index value, we find that significant differences in citing characteristics exist between engineering disciplines and other scientific fields. Our findings also reveal statistical differences in citing characteristics between subdisciplines found within the same engineering discipline.

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SHARAKHMETOV, SH., Estimates for moments of symmetric statistics, Theses of reports of the conference on probability theory and mathematical statistics dedicated to the 75th anniversary of Academician S. Kh

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/8 . Kovács. M. A. — Simon , A. ( 1998 ): The Components of the Real Exchange Rate in Hungary . NBH Working Paper, , 1998/3 . HCSO ( 1992 ): Consumer Price Statistics: The Renewed System of

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References [1] Ahsanullah , M. , Record statistics , Nova Science Publishers Commack , New York , 1995

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Izsák, J. 2003. DIVERSI 2.1: New version of a program package for calculating diversity and related statistics. Community Ecology 4:237-239. DIVERSI 2.1: New version of a program package for calculating diversity and related

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This paper contains applications of theorems of [1] for quadratic statistics which have constant regression on linear statistics. Two theorems are proved. The first is a sufficient condition which assumes that the characteristic function of a sample is an entire function. The second gives a new characterization of the normal distribution.

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In community ecology, randomization tests with problem specific test statistics (e.g., nestedness, functional diversity, etc.) are often applied. Researchers in such studies may want not only to detect the significant departure from randomness, but also to measure the effect size (i.e., the magnitude of this departure). Measuring the effect size is necessary, for instance, when the roles of different assembly forces (e.g., environmental filtering, competition) are compared among sites. The standard method is to calculate standardized effect size (SES), i.e., to compute the departure from the mean of random communities divided by their standard deviations. Standardized effect size is a useful measure if the test statistic (e.g., nestedness index, phylogenetic or functional diversity) in the random communities follows a symmetric distribution. In this paper, I would like to call attention to the fact that SES may give us misleading information if the distribution is asymmetric (skewed). For symmetric distribution median and mean values are equal (i.e., SES = 0 indicates p = 0.5). However, this condition does not hold for skewed distributions. For symmetric distributions departure from the mean shows the extremity of the value, regardless of the sign of departure, while in asymmetric distributions the same deviation can be highly probable and extremely improbable, depending on its sign. To avoid these problems, I recommend checking symmetry of null-distribution before calculating the SES value. If the distribution is skewed, I recommend either log-transformation of the test statistic, or using probit-transformed p-value as effect size measure.

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Abstract  

We show that inventive productivity can be described by two variables, Frenquency and Lifetime. For several samples of inventors, we show that the Exponential and Generalized Pareto distributions provide excellent goodness-of-fit to these variables. Furthermore, good fits to these distributions arises naturally from the statistics of exceedance. Thus, a better theoretical foundation and connection to environmental variables is shown for Frequency and Lifetime than has been shown for Lotka's Law.

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Abstract  

The well-known Poisson formula for counting statistics is generalized to the situation where the radioactive source studied, with mean lifetime 1/λ, decays apprecialy during the total time of observation T. A general expression is given for the modified probabilityλP(k) of observing k events in a short time interval to=T/n, where the results are averaged over the period of observation T. This corresponds to the experimental distribution which is obtained by pooling together all the n≫1 individual measurements of k made with a given source. The deviation from the simple Poisson law, which neglects decay, depends essentially on the quantity ν=λ·T. If ν is of the order of unity, the deformation is strong enough that it can serve as the basis of a new method for measuring the half-life of the nuclide involved.

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Abstract  

As in many other countries interlibrary lending (ILL) statistics were not systematically collected in Belgium until the seventies. Even today they give not always a complete coverage of the ILL situation in Belgium (an estimated 200.000 requests per year). However, electronic document ordering systems will change the present situation. They can be used to measure the performance of ILL, to improve its quality, to assess weaknesses in the ILL-system, to collect statistical data and to act as a clearinghouse for ILL billing.

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