Garbage data in circulation and entrance statistics: common mistakes and how to improve data accuracy

Abstract

The old saying about data remains true, "garbage in = garbage out." We often accept circulation and entrance statistics unquestioningly and decisions are made about collections, services, and policies based on those statistics. But these can have fundamental flaws. For example, circulation numbers for many academic libraries appears to be decreasing but I submit that a large part of this downtrend is connected to the proliferation of wireless networks and luxurious study spaces that cause students to use items more "in-house," but these statistics are often uncounted or not included in circulation numbers. I will show several ways that statistics could be undercounted or overcounted, and offer tips and solutions so that your circulation or entrance data reflects a truer, fuller picture of what is going on at your library.