Impact factor is a measure of the frequency with which the "average article" published in a given scholarly journal has been cited in a particular year or period and is often used to measure or describe the importance of a particular journal to its field. The Thomson-Reuters (formerly Institute for Scientific Information (ISI)) ranks, evaluates, and compares journals within subject categories and publishes the results in Journal Citation Reports. Find more information on the Library's Impact Factor webpage.
Altmetrics, or “alternative metrics,” are an emerging field of new methods for measuring the use and importance of scholarly articles, particularly in the sciences. As opposed to more traditional bibliometrics, such as Impact Factor, altmetrics provide article-level data and are based on new electronic sources of information, such as number of downloads and page views from a publisher, repository or online reference manager like Mendeley, or the amount of discussion generated in online venues such as Twitter or blogs. Find more information on the Library's Altmetrics webpage.
Google Analytics is a Google service that provides statistics for websites and mobile apps about their traffic. It also provides information on sales and conversaions, site and app performance, and audience characteristics and behavior. Google Analytics is free to use and and offers a premium version for a fee.