The rise of the Internet and digitally enabled means of disseminating scholarly research has led to a burgeoning interest in “altmetrics,” alternative measures of the impact and importance of scholarship that extend beyond traditional measures like citation counts. Funds from this grant support efforts by Vincent Lariviere and Stefanie Haustein of the University of Montreal and their colleague Cassidy Sugimoto of Indiana propose to dig deeper into the relative value and meaning of two specific altmetric indicators:  social media tweets and “saves” by popular bibliographic reference manager platforms.  The researcher team will match bibliographic and citation data from the Web of Science (linked with the same articles as they appear in PubMed and arXiv) with these forms of altmetric activity in order to answer a set of questions about the relationship between altmetric signals and the ultimate impact of a given work as traditionally measured in citation.  Particular focus will be given to the relationship, if any, between initial attention paid to preprints or working papers and the subsequent citation of formally published versions of those same papers.