Paul Donner

This paper discusses drawbacks of the percentile rank method for citation impact normalization which have hitherto been neglected in the bibliometrics literature. The transformation of citation counts to percentile ranks changes ratio scale data into ordinal scale data, for which the notions of the ratio between two values and of the magnitude of a difference between two values are not defined – a substantial loss of information. This distorts citation data particularly severely because the differences between citation counts adjacent in order in publication sets are greater for more highly cited publications and because highly cited publications are more scarce than non-highly cited ones. [...]

In this study we propose and evaluate a method to automatically identify the journal publications that are related to a Ph.D. thesis using bibliographical data of both items. We build a manually curated ground truth dataset from German cumulative doctoral theses that explicitly list the included publications, which we match with records in the Scopus database. We then test supervised classification methods on the task of identifying the correct associated publications among high numbers of potential candidates using features of the thesis and publication records. The results indicate that this approach results in good match quality in general and with the best results attained by the “random forest” classification algorithm.

This study investigates the potential of citation analysis of Ph.D. theses to obtain valid and useful early career performance indicators at the level of university departments. For German theses from 1996 to 2018 the suitability of citation data from Scopus and Google Books is studied and found to be sufficient to obtain quantitative estimates of early career researchers’ performance at departmental level in terms of scientific recognition and use of their dissertations as reflected in citations. Scopus and Google Books citations complement each other and have little overlap. Individual theses’ citation counts are much higher for those awarded a dissertation award than others. Departmental level estimates of citation impact agree ...

Cumulative dissertations are doctoral theses comprised of multiple published articles. For studies of publication activity and citation impact of early career researchers it is important to identify these articles and link them to their associated theses. Using a new benchmark data set, this paper reports on experiments of measuring the bilingual textual similarity between, on the one hand, titles and keywords of doctoral theses, and, on the other hand, articles’ titles and abstracts. The tested methods are cosine similarity and L1 distance in the Vector Space Model (VSM) as baselines, the language-indifferent methods Latent Semantic Analysis (LSA) and trigram similarity, and the language-aware methods fastText and Random Indexing (RI)...

We conduct an independent cluster validation study on published clustering solutions of a research testbed corpus, the Astro dataset of publication records from astronomy and astrophysics. We extend the dataset by collecting external validation data serving as proxies for the latent structure of the corpus. Specifically, we collect (1) grant funding information related to the publications, (2) data on topical special issues, (3) on specific journals’ internal topic classifications and (4) usage data from the main online bibliographic database of the discipline. The latter three types of data are newly introduced for the purpose of clustering validation and the rationale for using them for this task is set out.

By individually associating articles to basic or applied research, it is shown that basic articles are cited more frequently than applied ones. Dividing the subject categories of the Web of Science into a basic and an applied part, the mean field-normalization rate is referred to the applied or basic part depending on the research orientation of the paper analysed. By this approach, a distinct difference of the citations for the applied and basic parts of most subject categories is found. However, differences of the citation scores of applied and basic research organisations are found as well, but are less clear. The explanation is that applied and basic research organisations generally publish a mix of basic and applied articles. [...]

A perennial problem in bibliometrics is the appropriate distribution of authorship credit for coauthored publications. Several credit allocation methods and formulas have been introduced, but there has been little empirical validation as to which method best reflects the typical contributions of coauthors. This paper presents a validation of credit allocation methods using a new data set of author-provided percentage contribution figures obtained from the coauthored publications in cumulative PhD theses by authors from three countries that contain contribution statements. [...]

The present study is an evaluation of three frequently used institution name disambiguation systems. The Web of Science normalized institution names and Organization Enhanced system and the Scopus Affiliation ID system are tested against a complete, independent institution disambiguation system for a sample of German public sector research organizations. The independent system is used as the gold standard in the evaluations that we perform. We study the coverage of the disambiguation systems and, in particular, the differences in a number of commonly used bibliometric indicators. The key finding is that for the sample institutions, the studied systems provide bibliometric indicator values that have only a limited accuracy. [...]

This article reports the results of a study of the correctness of document type assignments in the commercial citation index database Web of Science (SCIE, SSCI, AHCI collections). The document type assignments for publication records are compared to those given on the official journal websites or in the publication full-texts for a random sample of 791 Web of Science records across the four document type categories articles, letters, reviews and others, according to the definitions of WoS. The proportion of incorrect assignments across document types and its influence on document specific normalized citations scores are analysed. It is found that document type data is correct in 94% of records. [...]