A sustainable e-book purchase model: A successful partnership

Published Jul 1, 2012 in the Newsletter Issue: Evolving collections & services -- July 2012

Sustainability is the key

The future of e-book adoption in academic libraries depends very much on how affordable they remain, and whether their content matches research and learning needs. In recent years, our library has increased its expenditures on e-books, while decreasing spending on monographs by more than five percent. In 2010-11, e-book purchases represented 73 percent of our spending on new electronic resources. The projected spending on e-books as a percent of the total budget for monographs is expected to rise from 20 percent to 45 percent in the next five years driven by the shift to e-book publishing. Outsell forecasts the scholarly and professional e-books market to double from 2010 to 2013 at the expense of print sales, which are forecast to decline by 4 percent yearly over the same period (Outsell, 2011).

Our library’s ongoing transition from print to electronic books has been aided by a long-term partnership with Elsevier to develop a sustainable e-book purchase model. When budgets decline and needs become more competitive, there is greater expectation of value. Our budget allocation, based on principles of zero-based budgeting, means that needs are reprioritized and usage is key in justifying value. In an environment of new patron demands and declining materials budgets, our library is less able to afford comprehensive collections, even at consortia discounts. In this scenario, buying what our patrons need — and will use — has to be the priority.

We seek purchasing models that enable us to acquire the right materials at the right time. Our university adopted the “just in time” model of acquisitions in early 2000 with encouraging use results. The Evidence-Based Selection (EBS) model offered by Elsevier is a just-in-time, patron-driven acquisition model that addresses our challenge to deliver instantaneous access to newly released e-books.

EBS increases value and impact

To see how the EBS model delivers value and serves user needs compared with librarian-selected titles, our library conducted a simple use study. We examined usage data for two EBS collections and compared them with the usage of an aggregator’s collection of e-books acquired through traditional means of selection. The two EBS collections attracted continuous high use in subsequent years. This suggests that the titles better match our users’ research needs.

When usage data for the three collections are plotted by the number of users against the number of titles, the EBS collections have a bell-shaped curve. The non-EBS collection results in a curve with a very long tail (Figure 1). The curves indicate the usage and distribution of use across the collections. The bell curves show a larger percent of titles with moderate to high use. In contrast, the long-tail curve shows a large portion attracting no or few uses, and a smaller portion attracting medium to high use. When a high percent of titles consumes a high percent of use, the entire collection is deemed better used. The use distribution is significant in demonstrating the value of a collection. Even if a complete or bundled collection purchased at a discounted price yields a respectable use count, it may not be deemed scalable if a very large percent of titles has no or marginal use.

Figure 1 - Curves tell distribution of use

Figure 1 - Curves tell the distribution of use

As one of the top research libraries in Asia, we strive to build collections with breadth and depth, but the fact of life is that we are increasingly less able to afford or justify “just-in-case” collections. EBS is a win-win for both libraries and publishers. It provides publishers with an incentive to make e-books more widely accessible as they are released, while libraries make the most of their reduced purchasing power. Optimizing access to e-content brings great benefit to researchers whose needs may have been undermined by budget constraints. More important, meeting the research needs of faculty, students and other users as reflected by usage statistics makes the strongest justification for funding purchase decisions.


Fooladi, Pooneh, May, Ned, and Worlock, Kate, Worldwide E-books, Market Size and Forecast Report 2009-2013, Outsell, Inc., June 2011.

About the Author

Gayle Chan

Head of Collection Development

The University of Hong Kong Libraries