Academic journal article Library Resources & Technical Services

Using Logistic Regression to Examine Multiple Factors Related to E-Book Use

Academic journal article Library Resources & Technical Services

Using Logistic Regression to Examine Multiple Factors Related to E-Book Use

Article excerpt

Academic libraries are struggling to understand the role of electronic books (e-books) in their collections. Not all potential book purchases are available electronically, and patrons frequently claim they prefer print. Yet, for reasons including appealing purchasing models, the desire to reach remote patrons, and evidence that e-books are used, libraries are increasingly buying e-books. The addition of this format to academic library collections raises the question of how to evaluate their usage. This is much more complicated than the parallel task of evaluating print book usage. Not only do subject matter, publication date, and publication type (e.g., reference book, conference proceedings, monograph, edited volume, etc.) affect usage (as for print), but e-books have a variety of user interfaces and are selected through a wider variety of methods. Like print, e-books can be selected through an approval plan or by firm order (i.e., a librarian selecting a specific book). They are often available to purchase as demand- driven acquisitions (DDA), evidence-based acquisitions, subscription packages, or as publisher collections. Open access e-books are also becoming available on several platforms, and libraries are adding these to their catalogs. Due to the range of selection methods, interfaces, and other characteristics, the variety of factors that affect whether an e-book gets used is much broader than those affecting print book use.

As libraries generally want to purchase items they expect will be used, many studies have attempted to identify factors that make e-books more likely to be used. Studies of e-book usage most often consider just one or two variables. For instance, are DDA more likely to be used than titles in packages? Do e-books in the sciences get used more than those for art? These questions are helpful, but the findings of such studies are only a beginning. A publisher package might receive more usage than an aggregator package, making it seem as if the quality of the publisher drives usage, when in fact the publisher package might simply have more current books or more relevant material than the aggregator package. E-book packages differ in so many ways that it can be difficult to know which feature drives use. In a study comparing usage of netLibrary and Ebrary collections, Tucker notes that differences could be related to the age of books in each collection or to user preferences for a particular interface. (1) Slater similarly notes that, in his comparison of Safari and netLibrary, "It is not possible to definitively determine ... if it is the contents of the collection or the presentation of the collection that motivated users to choose one ... over the other." (2) Since each book has a variety of features that could influence usage, there is a need for research that can simultaneously consider multiple factors.

A useful way to see which variables are most strongly correlated with usage is to combine multiple variables in a regression equation. By putting several variables into an equation that predicts an outcome, regression allows the researcher to separate the effects of each variable. To contribute to the methodology of measuring e-book use, this paper presents a logistic regression model that correlates several variables with the predicted usage of e-books in a large academic library. The research question is this: is it possible to identify characteristics of an e-book that will predict whether it will be used? The variables considered here are Library of Congress (LC) Classification (as a stand-in for subject), platform, publisher type, and usage of comparable print books. Though some variables of interest could not be included in the study, most significantly selection method, the methodology used can provide a model for others to expand upon and contribute to existing literature that has reported on how usage varies according to subject and publisher type.

Literature Review

Factors Considered in Previous Studies

Probably the most common question asked in the literature on e-books is which disciplines receive the heaviest usage. …

Search by... Author
Show... All Results Primary Sources Peer-reviewed

Oops!

An unknown error has occurred. Please click the button below to reload the page. If the problem persists, please try again in a little while.