DDA: Are We Meeting Collection Goals or Vendor Sales Targets?

Adelphi University Libraries started an e-book demand-driven acquisitions (DDA) program with Ebrary in January 2014. After one short-term loan a second use triggered a purchase. This trigger was determined by an analysis of how e-books were used in the subscription component of Ebrary, Academic Complete. Titles were added to the pool according to our slip plan profile with YBP. Librarians could also manually add e-book titles to the DDA pool. To see if our trigger point should be adjusted for our current DDA with ProQuest Ebook Central, statistics were harvested from the Ebrary administrative portal for January 2014 through January 2017 that show the use of items after they have triggered a purchase. This analysis covers the subsequent use of items that were triggered for purchase; the value of the DDA program compared to purchasing the e-books outright; and the value of including publishers such as Wiley that do not allow short-term loans in a DDA program. Using other Adelphi usage stats, this assessment covers the value of this DDA program for e-books compared to the usage of e-books in our subscription database and our firm ordered e-books