Usage statistics - confusing the reader
Call it what you will: data, usage data, metrics, look up, visit, session, usage statistics, quality assurance, review tools, counter compliant - whatever, what we are referring to is quantifiable discreet numbers which explain, hint or describe usage of something. They do not describe quality because if that item is the only thing in the library, well, it may be heavily used. But we can agree it was used, or used less or more than some other item or in some other time frame. Someone stepped over the door sill and through the turnstile and stayed for a bit (which we don't have in online, but you get the idea). To further confuse the reader, we can not profess to know why it got used. It could be for work in a course, or for personal continuing education.
So, when the library pulls together monthly usage statistics of something, the reader must be absolutely sure they know what they are counting. Are they counting number of unique users, unique sessions, sessions or transactions, or something else? And what is unique? Look for a definition of how that number is arrived at. Is it key strokes, pressing the enter key or unique IP addresses in a single transaction. Most database publishers provide definitions of what counter compliant data they are gathering so the library can copy that explanation. Usage statistics can lie or be used to befuddle the issue or they can illuminate.
If you really want to understand the background to how it works, go to http://www.projectcounter.org/about.html and read COUNTER: Counting Online Usage of Networked Electronic Resources. Meanwhile keep the library usage reporting simple and well defined.