Using citation analysis, sets of documents can be compared as independent
samples; for example, in terms of average citation counts using potentially
different reference sets. From this perspective, the size of samples matters
only for the identification of significant differences and estimating margins
of error. Using the percentile rank approach, differences among citation
distributions can be studied non-parametrically and in a single scheme.
Comparison among the sets clarifies that the different sizes of samples affect
the weighing of the probabilities and therefore the rankings.

Recently, aggregated journal-journal citation networks were made accessible
from the perspective of each journal included in the Science Citation Index see
(this http URL). The local matrices can be used to inspect the
relevant citation environment of a journal using statistical analysis and
visualization techniques from social network analysis. The inspection gives an
answer to the question what the local impact of this and other journals in the
environment is. In this study the citation environment of Angewandte Chemie was
analysed.