It has been variously referred to in the library literature devoted to collection development as books on demand, buy not borrow, collaborative collection development, demand-driven acquisitions, direct purchase, just-in-time acquisitions, just-in-time purchasing, on-demand acquisitions, patron-driven acquisitions, patron-initiated acquisitions, patron-initiated collection development, patron-initiated purchase, point-of-need acquisitions, purchase express, purchase-on-demand, reader-driven acquisitions, user-driven acquisitions, and user-initiated collection development (Alder, 2007; Allison, 2013; Clendenning, 2001; Dillon, 2011b; Emmert, 2004; Levine-Clark, 2011b; Miller, 2011; Nixon, Freeman, & Ward, 2010; Paulson, 2011; Pitcher, Bowersox, Oberlander, & Sullivan, 2010; Polanka & Delquie, 2011; Reel & Conn, 2010; Thompson, 2010; Tyler, 2011; Walker, 2012; Waller, 2013; Ward, 2002; Way, 2009). Regardless of the nomenclature, it is safe to say that patron-driven acquisitions (henceforth, PDA) has generated a great deal of interest and some enthusiasm in academic libraries and a correspondingly large amount of literature (Medeiros, 2012; Tyler, 2011; Waller, 2013; Wood, 2013). Lugg noted in 2011 that PDA "has become one of the most discussed ideas in the world of library collections" (p. 7). That same year, Walker somewhat rhetorically inquired whether PDA had reached a tipping point in U.S. academic libraries (Walker, 2012). A small number of enthusiasts have gone so far as to advocate that PDA programs become their libraries' primary method of collection development or be expanded as far as is possible (Jones, 2011; Levine-Clark, 2011a; Levine-Clark, 2011b; Spitzform, 2011; Spitzform & Sennyey, 2007).
What is PDA? Several working definitions have been proffered in the literature, but the definition provided by Ward (2012) in her guide to implementing and managing PDA may serve the best in its general applicability: "Patron-driven acquisitions (PDA) refers to a formal plan or program where librarians develop criteria for selecting books that will be bought based on patrons' requests or use" (p. 1). As Ward and others have noted, the purchase of print materials may be triggered by interlibrary loan (ILL) requests or by allowing patrons to request items via vendor records loaded into libraries' catalogs (Allison, 2013; Ward, 2012). With electronic book (e-book) PDA programs, e-books may have pro-rated short-term loans or purchase triggered by patrons' interactions with the e-books based on pre-set use or access triggers (Allison, 2013; Badics, 2012; Crane & Snyder, 2013; Dahl, 2013; Dillon, 2011b; Dinkins, 2012-2013; Fisher, Kurt, & Gardner, 2012; Herrera, 2012; Hruska, 2012; Mays, 2012; McLure & Hoseth, 2012; Medeiros, 2011; Reno, 2012-2013; Shepherd & Langston, 2013; Swords, 2011; Ward, 2012; Way & Garrison, 2011; Wiley & Clarage, 2012). As numerous authors have noted, and as can be inferred from Ward's definition, PDA potentially upends the traditional librarian/patron power structure where collecting and control over expenditure of the collection budget are concerned (Alder, 2007; Allison, 2013; Barnhart, 2010; Corbett, 2011; Dahl, 2012; Duncan & Carroll, 2011; Fisher, Kurt, & Gardner, 2012; Fyfe et al., 2012; Hodges, Preston, & Hamilton, 2010; Hruska, 2012; Lenares & Delquie, 2010; Lugg, 2011; Macicak & Schell, 2009; Medeiros, 2011, 2012; Miller, 2011; Polanka & Delquie, 2011; Reiners et al., 2012; Reno, 2012-2013; Riley, 2010; Schroeder, Wright, & Murdoch, 2010; Sens & Fonseca, 2013; Sharp & Thompson, 2010; E.S. Smith, 2011; S.A. Smith, 2011; Thompson, 2010; Waller, 2013; Walters, 2012). Lugg (2011) has called PDA a game-changer in the world of library collections and has discussed it at length as a disruptive technology.
As one might expect with a technology or technique that disturbs the library status quo, PDA has elicited concern among librarians, and much of this concern has centered on the potential failings of patrons as book selectors and on the several undesirable outcomes these failings might produce. Librarians' apprehensions about PDA have included: PDA books will be of too narrow interest and will therefore not circulate, patrons will spend wildly, patrons will unbalance or skew collections, and so forth. The literature review to follow will demonstrate that many of these concerns have received some attention in the literature of collection development. However, the authors of this study have found nothing that addresses the belief that PDA patrons will monopolize the books they have requested/purchased. The authors believe that it may be worthwhile to begin to remedy this dearth in the literature with a study of PDA books purchased at the University of Nebraska-Lincoln (UNL).
Unfortunately, UNL University Libraries' policies governing patron privacy hinder the authors from exploring directly whether individual patrons have monopolized PDA books through the mechanism of repeated circulations or through circulations with repeated circulation renewals. Thus, the following study will be limited to discovering whether the books' circulation records reveal that PDA books show a greater propensity toward being renewed and whether PDA books have received excessive circulation renewals, as compared to books acquired via more traditional avenues, i.e., approval plans' selections and librarians' orders.
Before proceeding, it would be worthwhile to provide a working definition of terms and to address a likely objection to the authors' approach. The study will be employing "monopolize" and "monopolistic" in their common, conversational sense: "to obtain exclusive possession of; keep entirely to oneself" (Monopolize, 2014). In essence, the study will attempt to see whether PDA books are being hogged, as compared to approval plan selected and librarian ordered books. This immediately raises the question of circulation recalls, for if the books in question may be recalled, then, strictly speaking, no actual monopolization of the books can occur, assuming that the borrowing patrons do not defy the recalls and refuse the rather sizeable resultant fines. The authors must concede that this is, technically, the case, but the authors would counter that the circulation recall objection privileges theory and neglects actual practice. In theory, UNL library patrons desiring a circulated book could request that it be recalled from its borrower. In actual practice, the books in question could be recalled, but they would not be immediately available to the patrons initiating the recalls. In fact, the recall-initiating patrons would be required by library policy to wait 10-14 days, depending upon circumstances, before the borrowing patrons would be compelled to return the recalled books. As one might expect, UNL Libraries' recall policies therefore likely have served as a barrier to the service's use, and in fact the service was not popular nor heavily used and was, in the period subsequent to this study, discontinued in favor of the UNL Libraries' more responsive and timely ILL services (Michael Straatmann, Circulation Manager, UNL University Libraries, personal communication, January 7, 2014). Thus, the reader may approach the study to follow as one of monopolistic use in observed effect, rather than in pure fact. Academic libraries with more aggressive recall policies could, presumably, see different patron behaviors.
REVIEW OF LITERATURE
PDA, beyond simply upending the librarian/patron power dynamic in collection development, presents the possibility of a myriad of problematic patron behaviors and resultant undesirable outcomes. Critics and supporters both have noted that PDA patrons request print books or access e-books whose utility, both to themselves and to their collections, is unknown, so there is a strong possibility that the purchased/accessed books will not meet their needs or that their needs did not require a purchase (Hussong-Christian & Georgen-Doll, 2010; Kuhn, 2004; Medeiros, 2011; Rottmann, 1991; Teaff, 2011). As a result, patrons could be left dissatisfied by their books or by the service itself.
The literature suggests that PDA critics who have worried that patrons will not appreciate the service or will not find their requested/purchased books worthwhile need not have worried. The literature that has addressed these questions shows that patrons have overwhelmingly supported the programs, felt that the books were useful, or felt that the books were good additions to their libraries' collections (Alder, 2007; Anderson et al., 2010; Barnhart, 2010; Bertuca et al., 2009; Brug & MacWaters, 2004; Chan, 2004; Clendenning, 2001; Comer & Lorenzen, 2007; Coopey & Snowman, 2006; Foss, 2007; Hussong-Christian & Georgen-Doll, 2010; Reel & Conn, 2010; Reynolds et al., 2010; Schmidt, 2012; Ward, 2002, 2011; Ward, Wray, & Debus-Lopez 2003; Wiley & Clarage, 2012). Perhaps some of the most in-depth research into patron satisfaction has been conducted at Oregon State University (OSU). Patrons surveyed by Hussong-Christian and Goergen-Doll favored OSU's PDA program, and the majority indicated that they would borrow their books again, would recommend them to colleagues, or would add them to reading lists. The open feedback portion of the survey indicated that 61.8% of patrons' comments were unqualifiedly positive and a mere 2.9% were purely negative (2010).
Other cautionary voices in the library literature have noted that patrons place ILL requests without first having consulted their libraries' catalogs or having assessed the adequacy of their libraries' holdings, which could result in ordering unnecessary or redundant books (Booth & O'Brien, 2011; Brug & MacWaters, 2004; Houle, 2004; Ingold, 2004; Richey, 2010; Watson, 2004; Wiley & Chrzastowski, 2010). In regard to ILL requests for locally held items or making requests without first consulting the library catalog, the ILL and PDA...