The decline in the concentration of citations, 1900–2007

This article challenges recent research (Evans, 2008) reporting that the concentration of cited scientific literature increases with the online availability of articles and journals. Using Thomson Reuters’ Web of Science, the present article analyses changes in the concentration of citations received (2- and 5-year citation windows) by papers published between 1900 and 2005.Three measures of concentration are used: the percentage of papers that received at least one citation (cited papers); the percentage of papers needed to account for 20%,50%, and 80% of the citations; and the Herfindahl-Hirschman index (HHI). These measures are used for four broad disciplines: natural sciences and engineering, medical fields, social sciences, and the humanities. All these measures converge and show that, contrary to what was reported by Evans, the dispersion of citations is actually increasing

The weakening relationship between the Impact Factor and papers' citations in the digital age

Historically, papers have been physically bound to the journal in which they were published but in the electronic age papers are available individually, no longer tied to their respective journals. Hence, papers now can be read and cited based on their own merits, independently of the journal's physical availability, reputation, or Impact Factor. We compare the strength of the relationship between journals' Impact Factors and the actual citations received by their respective papers from 1902 to 2009. Throughout most of the 20th century, papers' citation rates were increasingly linked to their respective journals' Impact Factors. However, since 1990, the advent of the digital age, the strength of the relation between Impact Factors and paper citations has been decreasing. This decrease began sooner in physics, a field that was quicker to make the transition into the electronic domain. Furthermore, since 1990, the proportion of highly cited papers coming from highly cited journals has been decreasing, and accordingly, the proportion of highly cited papers not coming from highly cited journals has also been increasing. Should this pattern continue, it might bring an end to the use of the Impact Factor as a way to evaluate the quality of journals, papers and researchers.Comment: 14 pages, 5 figure

The Geographic Distribution of US Executions

We review statistical patterns of the geographic distribution of US executions, compare them to homicides, and demonstrate extremely high degrees of concentration of executions in the modern period compared to previous historical periods. We further show that this unprecedented level of concentration has been increasing over the past 20 years. We demonstrate that it is virtually uncorrelated with factors related to homicides. Finally, we show that it corresponds to a statistical distribution associated with “self-reinforcing” processes: a power-law or exponential distribution. These findings stand whether we look at individual counties within death-penalty states, across the 50 states of the United States, or look at the international distribution of executions across countries in recent years. The substantive conclusion from the statistical patterns observed is that these cannot be explained merely by random variation around some general average. Rather, localities start down a path, then are reinforced in their pathways. There appears to be little to no logic about why certain counties are the high-use counties, whereas the vast majority have never executed a single individual in 40 years of experience with the modern death penalty, often in spite of thousands of homicides. Our research indicates that a main determinant of whether an individual will be executed is not the crime they commit, but the jurisdiction’s experience with executing others. This is not acceptable—legally, morally, or constitutionally

Pioneers, Submariners, or Thicket-builders: Which Firms Use Continuations in Patenting?

The continuations procedure within the U.S. patent system has been criticized for enabling firms to manipulate the patent review process for strategic purposes. Changes during the 1990s in patent procedures affected the incentives of applicants to exploit the continuations process, and additional reforms in continuations currently are being considered. Nonetheless, little is known about applicants' use of the three major types of continuations -- the Continuation Application (CAP), the Continuations-In-Part (CIP), and Divisions -- to alter the term and scope of patents. This paper analyzes patents issued from the three types of continuations to U.S. firms during 1981 - 2004 (with priority years 1981 - 2000), and links their frequency to the characteristics of patents, assignees and industries. We find that CIPs are disproportionately filed by R&D-intensive, small firms that patent heavily, and are more common in chemical and biological technologies. Patents resulting from CIP filings contain more claims and backward citations per patent on average, and cover relatively "valuable" inventions. In contrast, CAPs cover less valuable patents from large, capital-intensive firms that patent intensively, particularly in computer and semiconductor patents. We also analyze the effects of the 1995 change in patent term on continuation applications and find that the Act reduced the use of continuations overall, while shifting the output of CAPs toward "less important" patents.

The Swedish Paradox arises in Fast-Growing Sectors

The aim of this paper is to examine whether the previously observed gap between growth of R&D and economic performance, known as the ‘Swedish paradox’, is a general phenomenon across all sectors of the economy, or only occurs in specific industry segments. The dataset used for the analysis covers nearly the entire Swedish economy 1985-1998, divided into five broad sectors: Fast-growing industries, Slow-growing industries, Industrial outphasers, Fast- growing producer services and Other services. The growth of R&D, value added and research productivity is compared for these sectors and the largest gap between R&D and value added is located to the fast growing sectors of the economy. The Swedish paradox is therefore not necessarily a sign of weakness or deficiency of the innovation system, but rather indicates that long-term growth requires large investments in knowledge-building resources.Swedish paradox; sectors; R&D; research productivity; economic growth.