Libraries monitor their collection strength using a variety of indicators.
There are numerous collection assessment tools that document for libraries how their collections and services compare with similar institutions. Disciplinary information such as Digital Humanities: Questions and Answers addresses many issues related to trends and research directions.
Membership in national consortia such as the American Association of Universities (AAU) and the Association of Research Libraries (ARL) provide annual demographics about a library collection, size, staff and the operating costs.
The American Library Association and the The Bowker Annual of Library and Book Trade Information give statistical analysis of library resources.
For International impacts, there are a number of resources that describe library holdings, WorldCat, an international consortia of libraries; governmental funding structures, rankings and assessment exercises such as in the UK with SCONUL ; in Australia, Libraries Australia
Contains information on:
Recent trends in bogus metrics and predatory publishers encourage scholars to be very cautious about publishing claims regarding impact. There has been a call for what can be considered negative metrics. The Center for the Study of Interdisciplinarity has developed some lists and they appear in the following publications:
Several recent journal issues and articles have explored different metrics, and cover altmetrics in particular.
New Study Identifies Half-Life of Journal Articles ( LJ, January 2014)
Abbott, A., et al. (2010). Do metrics matter? Nature, 465(7300), 860-862.
Altmetrics Bibliography, version 1:10/14/2013 (includes content from January 2001-September 2013)
Armbruster, C. (2010). Whose metrics? citation, usage and access metrics as scholarly information service. Learned Publishing, 23(1), 33-38. doi:10.1087/20100107
This series of videos from Irish academics discuss some of the limitations of bibliometrics, and the importance of using a variety of methods to evaluate impact.
Many people have compiled interesting guides about how to introduce and present the growing resources on research and scholarly impacts. They continue to inspire me to revise this guide. Some of them are here: