Bibliometric indicators: the origin of their log-normal distribution and why they are not a reliable proxy for an individual scholar’s talent

There is now compelling evidence that the statistical distributions of extensive individual bibliometric indicators collected by a scholar, such as the number of publications or the total number of citations, are well represented by a Log-Normal function when homogeneous samples are considered. A Log-Normal distribution function is the normal distribution for the logarithm of the variable. In linear scale it is a highly skewed distribution with a long tail in the high productivity side. We are still lacking a detailed and convincing ab-initio model able to explain observed Log-Normal distributions-this is the gap this paper sets out to fill. Here, we propose a general explanation of the observed evidence by developing a straightforward model based on the following simple assumptions: (1) the materialist principle of the natural equality of human intelligence, (2) the success breeds success effect, also known as Merton effect, which can be traced back to the Gospel parables about the Talents (Matthew) and Minas (Luke), and, (3) the recognition and reputation mechanism. Building on these assumptions we propose a distribution function that, although mathematically not identical to a Log-Normal distribution, shares with it all its main features. Our model well reproduces the empirical distributions, so the hypotheses at the basis of the model are not falsified. Therefore the distributions of the bibliometric parameters observed might be the result of chance and noise (chaos) related to multiplicative phenomena connected to a publish or perish inflationary mechanism, led by scholars' recognition and reputations. In short, being a scholar in the right tail or in the left tail of the distribution could have very little connection to her/his merit and achievements. This interpretation might cast some doubts on the use of the number of papers and/or citations as a measure of scientific achievements. A tricky issue seems to emerge, that is: what then do bibliometric indicators really measure? This issue calls for deeper investigations into the meaning of bibliometric indicators. This is an interesting and intriguing topic for further research to be carried out within a wider interdisciplinary investigation of the science of science, which may include elements and investigation tools from philosophy, psychology and sociology

Academic vs. biological age in research on academic careers: a large-scale study with implications for scientifically developing systems

Biological age is an important sociodemographic factor in studies on academic careers (research productivity, scholarly impact, and collaboration patterns). It is assumed that the academic age, or the time elapsed from the first publication, is a good proxy for biological age. In this study, we analyze the limitations of the proxy in academic career studies, using as an example the entire population of Polish academic scientists and scholars visible in the last decade in global science and holding at least a PhD (N = 20,569). The proxy works well for science, technology, engineering, mathematics, and medicine (STEMM) disciplines; however, for non-STEMM disciplines (particularly for humanities and social sciences), it has a dramatically worse performance. This negative conclusion is particularly important for systems that have only recently visible in global academic journals. The micro-level data suggest a delayed participation of social scientists and humanists in global science networks, with practical implications for predicting biological age from academic age. We calculate correlation coefficients, present contingency analysis of academic career stages with academic positions and age groups, and create a linear multivariate regression model. Our research suggests that in scientifically developing countries, academic age as a proxy for biological age should be used more cautiously than in advanced countries: ideally, it should be used only for STEMM disciplines.127Scientometric

A Century of American Economic Review

Using information collected from American Economic Review publications of the last 100 years, we try to provide answers to various questions: Which are the top AER publishing institutions and countries? Which are the top AER papers based on citation success? How frequently is someone able to publish in AER? How equally is citation success distributed? Who are the top AER publishing authors? What is the level of cooperation among the authors? What drives the alphabetical name ordering? What are the individual characteristics of the AER authors, editors, editorial board members, and referees? How frequently do women publish in AER? What is the relationship between academic age, publication performance, and citation success? What are the paper characteristics? What influences the level of technique used in articles? Do connections have an influence on citation success? Who receives awards? Can awards increase the probability of publishing in AER at a later stage?American Economic Review, Publishing Economics, Rankings, Cooperation, Authors, Editors, Board Members, Referees, Connections, Awards, Paper Characteristics, Economic History, History of Economic Thought

A Century of American Economic Review

Using information collected from American Economic Review publications of the last 100 years, we try to provide answers to various questions: Which are the top AER publishing institutions and countries? Which are the top AER papers based on citation success? How frequently is someone able to publish in AER? How equally is citation success distributed? Who are the top AER publishing authors? What is the level of cooperation among the authors? What drives the alphabetical name ordering? What are the individual characteristics of the AER authors, editors, editorial board members, and referees? How frequently do women publish in AER? What is the relationship between academic age, publication performance, and citation success? What are the paper characteristics? What influences the level of technique used in articles? Do connections have an influence on citation success? Who receives awards? Can awards increase the probability of publishing in AER at a later stage?American Economic Review, publishing economics, rankings, cooperation,authors, editors, board members, referees, connections, awards, paper characteristics, economic history, history of economic thoug

Impact Factor: outdated artefact or stepping-stone to journal certification?

A review of Garfield's journal impact factor and its specific implementation as the Thomson Reuters Impact Factor reveals several weaknesses in this commonly-used indicator of journal standing. Key limitations include the mismatch between citing and cited documents, the deceptive display of three decimals that belies the real precision, and the absence of confidence intervals. These are minor issues that are easily amended and should be corrected, but more substantive improvements are needed. There are indications that the scientific community seeks and needs better certification of journal procedures to improve the quality of published science. Comprehensive certification of editorial and review procedures could help ensure adequate procedures to detect duplicate and fraudulent submissions.Comment: 25 pages, 12 figures, 6 table

The Power of Posner: A Study of Prestige and Influence in the Federal Judiciary

Some judges have a disproportionate influence over the American judiciary; existing research has shown Judge Richard Posner is one of those judges. Our goal was to identify and determine how Judge Posner’s influence has changed over time. To measure and track his influence, we collected and compared citation and invocation data from three distinct time frames. While these measurements are imperfect, they can help illustrate the level of influence and prestige Judge Posner enjoys. The existing literature led us to expect Judge Posner’s early citation rates to be low. After several years on the bench, the citation rates for each opinion should rise dramatically. By contrast, Judge Posner’s citation rates are exceptionally high from the outset while more recent opinions actually have lower citation rates

School-to-Career and Post-Secondary Education: Evidence from the Philadelphia Educational Longitudinal Study

We study a set of programs implemented in Philadelphia high schools that focus on boosting post-secondary enrollment. These programs are less career oriented than traditional school-to-work programs, but are consistent with the broadening of the goals of school-to-work to emphasize post-secondary education. The Philadelphia Longitudinal Educational Study (PELS) data set that we examine contains an unusually large amount of information on individuals prior to placement in STC programs. We use the detailed information in the PELS to study the process of selection into these programs and to examine their impact on a set of mainly schooling-related outcomes during and after high school, although we also consider their impact on non-academic outcomes. The data point to positive effects of these programs on high school graduation and on both academic and non-academic awards in high school, and similar negative effects on dropping out of high school. The results also suggest positive effects on aspirations for higher education and on college attendance. In addition, there is some evidence that these programs are more effective in increasing college attendance and aspirations among at-risk youths.

A Phoenix in Flames? Portfolio Choice and Violence in Civil War in Rural Burundi

This paper challenges the idea that farmers revert to subsistence farming when confronted with violence from civil war. Macro-economic evidence on economic legacies of civil war suggests that civil wars, while obviously disastrous in the short run, do not need to have persistent effects on long term economic outcomes. New micro-level studies are ambiguous about the impact of civil war for welfare. Several studies find long lasting negative effects, particularly through reduced human capital formation while others for example report increased participation in collective action programs and the emergence of local institutions. We investigate to what extend individual incentives for investments are affected by civil war. Using several rounds of (panel) data at the farm and community level, we find that farmers in Burundi who are confronted with civil war violence in their home communities increase export and cash crop growing activities, invest more in public goods, and reveal higher levels of subjective welfare evaluations. We interpret this in the light of similar recent micro-level evidence that points to post-traumatic growth effects after (civil) war fare. Our results are confirmed across specifications as well as in robustness analyses

Scientists who engage with society perform better academically

Most scientific institutions acknowledge the importance of opening the so-called 'ivory tower' of academic research through popularization, industrial collaboration or teaching. However, little is known about the actual openness of scientific institutions and how their proclaimed priorities translate into concrete measures. This paper gives an idea of some actual practices by studying three key points: the proportion of researchers who are active in wider dissemination, the academic productivity of these scientists, and the institutional recognition of their wider dissemination activities in terms of their careers. We analyze extensive data about the academic production, career recognition and teaching or public/industrial outreach of several thousand of scientists, from many disciplines, from France's Centre National de la Recherche Scientifique. We find that, contrary to what is often suggested, scientists active in wider dissemination are also more active academically. However, their dissemination activities have almost no impact (positive or negative) on their careers