An index for evaluating journals in a small domestic citation index database whose citation rate is generally very low: A test based on the Korea Citation Index (KCI) database

This study describes the meaning of and the formula for S-index, which is a novel evaluation index based on the number of citations of each article in a particular journal and the rank of the article according to the number of citations. This study compares S-index with Impact Factor (IF), which is the most well-known evaluation index, using the Korea Citation Index data. It is shown that S-index is positively correlated with the number of articles published in a journal. Tapered h-index (h_T-index), which is based on all articles of a journal like S-index, is compared with S-index. It is shown that there is a very strong positive correlation between S-index and h_T-index. Although S-index is similar to h_T-index, S-index has a slightly better differentiating power and ranks the journal with evenly cited articles higher.     

Modifying h-index by allocating credit of multi-authored papers whose author names rank based on contribution

In the present work we introduce a modification of the h-index for multi-authored papers with contribution based author name ranking. The modified h-index is denoted by h_mc-index. It employs the framework of the h_m-index, which in turn is a straightforward modification of the Hirsch index, proposed by Schreiber. To retain the merit of requiring no additional rearrangement of papers in the h_m-index and in order to overcome its shortage of benefiting secondary authors at the expense of primary authors, h_mc-index uses combined credit allocation (CCA) to replace fractionalized counting in the h_m-index. The h_m-index is a special form of h_mc-index and fits for papers with equally important authors or alphabetically ordered authorship. There is a possibility of an author of lower contribution to the whole scientific community obtaining a higher h_mc-index. Rational h_mc-index, denoted by h_mcr-index, can avoid it. A fictitious example as a model case and two empirical cases are analyzed. The correlations of the h_mcr-index with the h-index and its several variants considering multiple co-authorship are inspected with 30 researchers’ citation data. The results show that the h_mcr-index is more reasonable for authors with different contributions. A researcher playing more important roles in significant work will obtain higher h_mcr-index.     

HistCite analysis of papers constituting the h index research front

In the Essential Science Indicators (Thomson Reuters), a research front exists to the h index (entitled “GOOGLE SCHOLAR H-INDEX; SCIENCE CITATION INDEX; GENERALIZED HIRSCH H-INDEX; H INDEX; GOOGLE SCHOLAR CITATIONS”) consisting of a group of highly cited papers. We used HistCite to analyze the structure and relationships of the 45 papers forming the h index research front. Since we were interested in the topics of research on the h index at the front, we classified each paper according to its main topic. Six topics (inductively generated) were sufficient to classify the 45 papers: (1) citation database, (2) empirical validation study, (3) new application, (4) theoretical analysis, (5) new index development, and (6) literature review.     

The citation triad: An overview of a scientist's publication output based on Ferrers diagrams

In a recent work by Anderson, Hankin, and Killworth (2008), Ferrers diagrams and Durfee squares are used to represent the scientific output of a scientist and construct a new h-based bibliometric indicator, the tapered h-index (h_T). In the first part of this paper we examine h_T, identifying its main drawbacks and weaknesses: an arbitrary scoring system and an illusory increase in discrimination power compared to h. Subsequently, we propose a new bibliometric tool, the citation triad (CT), that better exploits the information contained in a Ferrers diagram, giving a synthetic overview of a scientist's publication output. The advantages of this new approach are discussed in detail. Argument is supported by several examples based on empirical data.     

Real and rational variants of the h-index and the g-index

The definitions of the rational and real-valued variants of the h-index and g-index are reviewed. It is shown how they can be obtained both graphically and by calculation. Formulae are derived expressing the exact relations between the h-variants and between the g-variants. Subsequently these relations are examined. In a citation context the real h-index is often, but not always, smaller than the rational h-index. It is also shown that the relation between the real and the rational g-index depends on the number of citations of the article ranked g + 1. Maximum differences between h, h_r and h_rat on the one hand and between g, g_r and g_rat on the other are determined.     

A mathematical characterization of the Hirsch-index by means of minimal increments

The minimum configuration to have a h-index equal to h is h papers each having h citations, hence h² citations in total. To increase the h-index to h + 1 we minimally need (h + 1)² citations, an increment of I₁(h) = 2h + 1. The latter number increases with 2 per unit increase of h. This increment of the second order is denoted I₂(h) = 2.If we define I₁ and I₂ for a general Hirsch configuration (say n papers each having f(n) citations) we calculate I₁(f) and I₂(f) similarly as for the h-index. We characterize all functions f for which I₂(f) = 2 and show that this can be obtained for functions f(n) different from the h-index. We show that f(n) = n (i.e. the h-index) if and only if I₂(f) = 2, f(1) = 1 and f(2) = 2.We give a similar characterization for the threshold index (where n papers have a constant number C of citations). Here we deal with second order increments I₂(f) = 0.     

Monotonicity and the Hirsch index

The Hirsch index is a number that synthesizes a researcher's output. It is the maximum number h such that the researcher has h papers with at least h citations each. Woeginger [Woeginger, G. J. (2008a). An axiomatic characterization of the Hirsch-index. Mathematical Social Sciences, 56(2), 224–232; Woeginger, G. J. (2008b). A symmetry axiom for scientific impact indices. Journal of Informetrics, 2(3), 298–303] characterizes the Hirsch index when indices are assumed to be integer-valued. In this note, the Hirsch index is characterized, when indices are allowed to be real-valued, by adding to Woeginger's monotonicity two axioms in a way related to the concept of monotonicity.     

Review of Conservation of Old Art Objects in Japan

Abstract

By using X-ray powder diffraction to identify the crystalline constituents of ceramics, especially porcelains, a considerable amount of information can be obtained from a very small sample. The characteristic mineral in hard-paste porcelains, stonewares and highfired earthenwares is shown to be mullite, an aluminium silicate, 3Al₂O₃. 2SiO₂, (A.S:T.M. 15–776); where there is a high calcium content aluminium silicates may occur e.g. anorthite, CaO. Al₂O₃. 2SiO₂, (A.S.T.M.10–379) and gehlenite 2CaO. Al₂O₃. SiO₂, (A.S.T.M.9–216). Among the soft-paste porcelains, whitlockite, β calcium orthophosphate, Ca₃(PO₄)₂, (A.S.T.M. 9–169), is typical of those containing bone-ash, and enstatite, magnesium meta silicate, MgO. SiO₂ (A.S.T.M.7–216) is typical of those containing soapstone. The glassy-frit porcelains generally contain a calcium silicate, wollastonite or pseudowol1astonite, CaO. SiO₂, (A.S.T.M.10–487 and 10–486). In addition, silica–either as α quartz or cristobalite–may occur in varying proportions in all these bodies.     

The citation speed index: A useful bibliometric indicator to add to the h index

The scientific impact of a publication can be determined not only based on the number of times it is cited but also based on the citation speed with which its content is noted by the scientific community. Here we present the citation speed index as a meaningful complement to the h index: whereas for the calculation of the h index the impact of publications is based on number of citations, for the calculation of the speed index it is the number of months that have elapsed since the first citation, the citation speed with which the results of publications find reception in the scientific community. The speed index is defined as follows: a group of papers has the index s if for s of its N_p papers the first citation was at least s months ago, and for the other (N_p ? s) papers the first citation was ≤s months ago.     

Relations among the h-, g-, ψ-, and p-index and offset-ability

We show that the h-index, g-index, ψ-index, and p-index, are related through the inequalities: h ≤ p ≤ g ≤ ψ. Moreover, this relation is proved theoretically in the mathematical framework of Lotkaian informetrics and is verified empirically by using two datasets from the Web of Science in the fields of electrochemistry and gerontology. For quantifying their relations, we estimate the g-index, ψ-index, and their cores and ratios of cores via a second-order Taylor series when the e-index, h-index, and C₁ (the maximum number of citations received by a paper) are known. Then we find for the two empirical cases, that ratios of cores and average citations are approximately stable. Compared with the g-index, the offset-ability of the h-index decreases by 20% but the average citations increase by 20%. A similar observation holds for the comparison of the g-index and ψ-index. To explore the possible applications of cores of different indices, we apply them to extract the core structure of a network. The h-core is the most efficient, while the ψ-core includes more nodes with high betweenness.     

A case study of the arbitrariness of the h-index and the highly-cited-publications indicator

The arbitrariness of the h-index becomes evident, when one requires q × h instead of h citations as the threshold for the definition of the index, thus changing the size of the core of the most influential publications of a dataset. I analyze the citation records of 26 physicists in order to determine how much the prefactor q influences the ranking. Likewise, the arbitrariness of the highly-cited-publications indicator is due to the threshold value, given either as an absolute number of citations or as a percentage of highly cited papers. The analysis of the 26 citation records shows that the changes in the rankings in dependence on these thresholds are rather large and comparable with the respective changes for the h-index.     

How to modify the g-index for multi-authored manuscripts

A recently suggested modification of the g-index is analysed in order to take multiple coauthorship appropriately into account. By fractionalised counting of the papers one can obtain an appropriate measure which I call g_m-index. Two fictitious examples for model cases and two empirical cases are analysed. The results are compared with two other variants of the g-index which have also recently been proposed. Only the g_m-index shows the correct behaviour when datasets are aggregated. The interpolated and continuous versions of the g-index and its variants are also discussed. For an intuitive comparison of the determination of the investigated variants of the h-index and the g-index, a visualization of the citation records is utilized.     

Axiomatizing the Hirsch index: Quantity and quality disjoined

Scientific impact indexes like h are responsive to two parameters: the researcher's productivity given by the number of her published papers (an aspect of quantity) and citations (an aspect of quality). In this paper I prove that the two parameters can be treated separately: the index h can be axiomatized by appealing (1) only to axioms that allow for productivity changes, but do not require taking into account distinct situations in which a researcher's papers received different numbers of citations or (2) only to axioms that allow for changes in the number of citations received by the researcher's papers, but do not require changes in scientific productivity. The axioms used are weak. Specifically, monotonicity is avoided.     

Empirical study of L-Sequence: The basic h-index sequence for cumulative publications with consideration of the yearly citation performance

Most current h-type indicators use only a single number to measure a scientist's productivity and impact of his/her published works. Although a single number is simple to calculate, it fails to outline his/her academic performance varying with time. We empirically study the basic h-index sequence for cumulative publications with consideration of the yearly citation performance (for convenience, referred as L-Sequence). L-Sequence consists of a series of L factors. Based on the citations received in the corresponding individual year, every factor along a scientist's career span is calculated by using the h index formula. Thus L-Sequence shows the scientist's dynamic research trajectory and provides insight into his/her scientific performance at different periods. Furthermore, L_∝, summing up all factors of L-Sequence, is for the evaluation of the whole research career as alternative to other h-index variants. Importantly, the partial factors of the L-Sequence can be adapted for different evaluation tasks. Moreover, L-Sequence could be used to highlight outstanding scientists in a specific period whose research interests can be used to study the history and trends of a specific discipline.     

Parametrization of the solvent action on modern artists' paint systems

A solvent action parametrization scheme has been developed combining relevant parameters of the solvent action on modern artists' paints to characterize the solvation and dissolving properties of different binding media. The new system combines different concepts used in solvent chemistry. It is based on the normalized and solute-dependent dimension [hδ_H + eE_T(30)cv]^N. It comprises a polarity value E_T(30)cv as the magnitude of the enthalpy, and a combined value representing the cavitation energy δ_H as an entropy-influencing factor. Forty-eight solvents were divided into five subgroups based on their interaction and structural properties. This binary scheme permits to reliably quantify spaces of efficiency. The graphical selectivity of the scheme was applied to four binding media systems (oil, alkyd, acrylic-, and acrylic-polystyrene) by determination of the swelling capacity of 48 solvents. The graphical visualization of the systematic parametrization of solvents permits one to judge the intermolecular interaction and other effects of solvation relevant to the restoration of painted artwork.     

Technological research in the EU is less efficient than the world average. EU research policy risks Europeans’ future

We have studied the efficiency of research in the EU by a percentile-based citation approach that analyzes the distribution of country papers among the world papers. Going up in the citation scale, the frequency of papers from efficient countries increases while the frequency from inefficient countries decreases. In the percentile-based approach, this trend, which is uniform at any citation level, is measured by the e_p index that equals the P_{top 1%}/P_{top 10%} ratio. By using the e_p index we demonstrate that EU research on fast-evolving technological topics is less efficient than the world average and that the EU is far from being able to compete with the most advanced countries. The e_p index also shows that the USA is well ahead of the EU in both fast- and slow-evolving technologies, which suggests that the advantage of the USA over the EU in innovation is due to low research efficiency in the EU. In accord with some previous studies, our results show that the European Commission’s ongoing claims about the excellence of EU research are based on a wrong diagnosis. The EU must focus its research policy on the improvement of its inefficient research. Otherwise, the future of Europeans is at risk.     

How to derive an advantage from the arbitrariness of the g-index

The definition of the g-index is as arbitrary as that of the h-index, because the threshold number g² of citations to the g most cited papers can be modified by a prefactor at one's discretion, thus taking into account more or less of the highly cited publications within a dataset. In a case study I investigate the citation records of 26 physicists and show that the prefactor influences the ranking in terms of the generalized g-index less than for the generalized h-index. I propose specifically a prefactor of 2 for the g-index, because then the resulting values are of the same order of magnitude as for the common h-index. In this way one can avoid the disadvantage of the original g-index, namely that the values are usually substantially larger than for the h-index and thus the precision problem is substantially larger; while the advantages of the g-index over the h-index are kept. Like for the generalized h-index, also for the generalized g-index different prefactors might be more useful for investigations which concentrate only on top scientists with high citation frequencies or on junior researchers with small numbers of citations.