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Descriptive statistical techniques for librarians
564
Book Reviews
In the age of Information Power,’ the new guidelines for school library media programs, this volume is of great worth. It is valuable not only for its immediate application to the management of onhne services, but as a model of how to think about the choices that confront us, and how to communicate these choices to administrators and boards of directors in a way that will provoke action as well as respect. REFERENCE 1. American Association for School Librarians and Association for Educational Communications and Technology. Information Power; Guidelines for School Media Programs. Chicago, IL: American Library Association, 1988. Conneily School Potomac,
LINDA KNOWLES
MD
Descriptive Statistical Techniques for Librarians. A.W. HAFNER. American Library Association, cago and London (1989). vii + 261 pp., $20.00 pbk., ISBN o-8389-0510-2.
Chi-
As the author notes in his preface, this book “is intended to serve as a textbook for a first course in research methods for library and information science students” (p. v). It is also intended to serve as a reference manual for practitioners. The author’s stated objective is to explain how statistical methods are used and how to evaluate and interpret the meaning of the various statistical measures. “No effort is made to train the reader to become a statistician” (p. v.). The work covers statistical techniques that are, in Hafner’s opinion, the “most useful, most widely referenced in library journals, and most essential for further study” (p. v). As the ti!le indicates, however, the work is limited to descriptive statistics. Each of the six chapters opens with “learning objectives” and concludes with summaries of critical concepts, definitions f)f key terms, quizzes (with answers), and discussion questions and problems. As Hafner notes, the problems represent “many areas of librarianship and the business side of information management” (p. vi). These learning aids seem to be well conceived and should help the reader to review the preceding material. The first chapter provides useful definitions of common statistical terms, though one could argue that a few of the definitions are cursory. For example, user surveys are defined as “carefully planned questionnaires or interviews designed to assess user satisfaction or dissatisfaction” (p. 4). In fact, user surveys are not limited to questionnaires and interviews nor to assessing user satisfaction and dissatisfaction. This chapter also includes measurement and types of scales. Chapter two covers rounding; ratio, proportion, and percents; comparison measure analyses; data point labeling and summation notation; and a brief discussion of quantity and quality. The discussion of quantity and quality seems somewhat out of place in this chapter, if not the book, and is too short to deal adequately with the complex issues related to output measures, standards, and mission statements. The section on comparison measure analyses is useful and includes techniques, such as benefit-cost analysis, not typically found in a statistics text. The next chapter presents a good introduction to different types of graphs and how they can be used and provides several guidelines for designing graphs. However, the degree to which Hafner describes how to construct a specific type of graph varies. Chapter three also covers data arrays and frequency distributions and has a section (which seems to be out of sequence) on relative and cumulative distributions. Chapters four and five, like the preceding chapters, reflect modest, attainable objectives and provide appropriate, useful examples of the techniques under consideration. In the fourth chapter Hafner addresses measures of central tendency such as mode, median, and mean. His descriptions of how to calculate such measures are straightforward and clear. Much the same characteristics hold true for chapter five, which covers measures of variability such as percentiles, mean deviation, standard deviation, and coefficient of variation. Hafner does a nice job of explaining standard deviation and how it is used. It is not clear why he chose to insert a short section on “Economies and Diseconomies of Scale” in this chapter. Regression and correlation analysis are treated in the final chapter. In some texts these techniques are considered to be inferential (rather than descriptive) statistics, but they seem appropriate for this work regardless of such distinctions. Regression and correlation are relatively difficult techniques to deal with in one chapter, and readers may find it desirable to turn to supplementary textbooks.
Book Reviews
565
The book closes with a list of answers to many of the discussion questions and problems, a bibliography, and an index. The bibliography is fairly short; the index appears to be quite adequate. Descriptive Statistical Techniques for Librarians is a well conceived, clearly written introduction to a number of descriptive statistical techniques which should be familiar to most librarians. Though a bit skimpy in places, the text generally does a good job of defining and explaining basic terms and techniques. The work is not overly ambitious, i.e., the author does not attempt to cover the waterfront of statistics in one small book. Nor does the work require that readers have any previous background in statistics, though the author does assume a “familiarity” with algebra. This textbook, which appears to be a substantially revised and expanded version of an earlier work by Hafner,’ is recommended for those wanting a succinct, generally nontheoretical introduction to basic descriptive statistics. Readers desiring some additional background in statistical techniques may wish to refer to books by Jaeger and Rowntree.’ REFERENCES 1. Hafner, A.W. Descriptive Statistics for Librarians. Chicago: Midwest Health Science Library Network, 1982. 2. Jaeger, R.M. Statistics; A Spectator Sport. Beverly Hills, CA: Sage Publications, 1983. Rowntree, D., Statistics Without Tears; A Primer for Non-Mathematicians. New York: Charles Scribner’s Sons, 1981.
School of Library and Informational University of Missouri-Columbia Columbia, MO
Science
RONALD R. POWELL
Guide to the Evaluation
of Library Collections. B. LOCKETT (ED.). Subcommittee on Guidelines for Collection Development, Collection Management and Development Committee, Resources Section, Resources and Technical Services Division, American Library Association, Chicago (1989). v + 25 pp., $5.00, ISBN 0-8389-3370-X.
This book is the second in the series of Collection Management and Development Guides published by the Resources Section of the Resources and Technical Services Division of the American Library Association. It combines the evaluation section of Guidelines for Collection Development, edited by D. L. Perkins (1979), and “Guide to Collection Evaluation through Use and User Studies” by D. E. Christiansen et al., published in Library Resources and Technical Services 27 (1983). The guide’s purpose is to provide a statement of principles and methods by which a library can determine the extent to which it satisfies its users and fulfills its stated mission by acquiring the needed books, journals, and other materials. Meant as a checklist of possible methods, the guide is brief, totaling 17 pages of text. In outline format, it lists methods of evaluation, the types of libraries for which they can be used, and the advantages and disadvantages of each. The methods, broadly divided into those that are collection-centered and those that are user-centered, are not described in detail. For further information, the reader is referred to the guide’s extensive bibliography, which is organized by evaluation methods (e.g., circulation studies, citation studies, conspectus format, interlibrary loan, user surveys). The guide identifies its intended audience as those who practice collection development, administrators, collection development officers and policy makers, and accreditation committees. While the guide might be too elementary for some practicing professionals in this area, it would be quite useful for library school students and professionals new to collection evaluation. Its authors acknowledge that the methods listed are “heavily slanted to books and periodicals, although methods for other information formats are included when they exist.” In this respect, the guide seems behind the times, as libraries increasingly obtain access to information in nonprint format and through resource sharing. Nonetheless, it provides a succinct and valuable overview to the range of methods available and the limits of their usefulness. The guide does not identify the first in its series (Guide for Writing a Bibliographer’s Manual, ALA, 1987), but does indicate that the next will be Guide for Written Collection Policy Statements. Perhaps this coming guide will give nonprint sources the prominence they deserve. School of Library and Information Catholic University of America Washington, DC
Science
JEAN L. PREER
Book Reviews
In the age of Information Power,’ the new guidelines for school library media programs, this volume is of great worth. It is valuable not only for its immediate application to the management of onhne services, but as a model of how to think about the choices that confront us, and how to communicate these choices to administrators and boards of directors in a way that will provoke action as well as respect. REFERENCE 1. American Association for School Librarians and Association for Educational Communications and Technology. Information Power; Guidelines for School Media Programs. Chicago, IL: American Library Association, 1988. Conneily School Potomac,
LINDA KNOWLES
MD
Descriptive Statistical Techniques for Librarians. A.W. HAFNER. American Library Association, cago and London (1989). vii + 261 pp., $20.00 pbk., ISBN o-8389-0510-2.
Chi-
As the author notes in his preface, this book “is intended to serve as a textbook for a first course in research methods for library and information science students” (p. v). It is also intended to serve as a reference manual for practitioners. The author’s stated objective is to explain how statistical methods are used and how to evaluate and interpret the meaning of the various statistical measures. “No effort is made to train the reader to become a statistician” (p. v.). The work covers statistical techniques that are, in Hafner’s opinion, the “most useful, most widely referenced in library journals, and most essential for further study” (p. v). As the ti!le indicates, however, the work is limited to descriptive statistics. Each of the six chapters opens with “learning objectives” and concludes with summaries of critical concepts, definitions f)f key terms, quizzes (with answers), and discussion questions and problems. As Hafner notes, the problems represent “many areas of librarianship and the business side of information management” (p. vi). These learning aids seem to be well conceived and should help the reader to review the preceding material. The first chapter provides useful definitions of common statistical terms, though one could argue that a few of the definitions are cursory. For example, user surveys are defined as “carefully planned questionnaires or interviews designed to assess user satisfaction or dissatisfaction” (p. 4). In fact, user surveys are not limited to questionnaires and interviews nor to assessing user satisfaction and dissatisfaction. This chapter also includes measurement and types of scales. Chapter two covers rounding; ratio, proportion, and percents; comparison measure analyses; data point labeling and summation notation; and a brief discussion of quantity and quality. The discussion of quantity and quality seems somewhat out of place in this chapter, if not the book, and is too short to deal adequately with the complex issues related to output measures, standards, and mission statements. The section on comparison measure analyses is useful and includes techniques, such as benefit-cost analysis, not typically found in a statistics text. The next chapter presents a good introduction to different types of graphs and how they can be used and provides several guidelines for designing graphs. However, the degree to which Hafner describes how to construct a specific type of graph varies. Chapter three also covers data arrays and frequency distributions and has a section (which seems to be out of sequence) on relative and cumulative distributions. Chapters four and five, like the preceding chapters, reflect modest, attainable objectives and provide appropriate, useful examples of the techniques under consideration. In the fourth chapter Hafner addresses measures of central tendency such as mode, median, and mean. His descriptions of how to calculate such measures are straightforward and clear. Much the same characteristics hold true for chapter five, which covers measures of variability such as percentiles, mean deviation, standard deviation, and coefficient of variation. Hafner does a nice job of explaining standard deviation and how it is used. It is not clear why he chose to insert a short section on “Economies and Diseconomies of Scale” in this chapter. Regression and correlation analysis are treated in the final chapter. In some texts these techniques are considered to be inferential (rather than descriptive) statistics, but they seem appropriate for this work regardless of such distinctions. Regression and correlation are relatively difficult techniques to deal with in one chapter, and readers may find it desirable to turn to supplementary textbooks.
Book Reviews
565
The book closes with a list of answers to many of the discussion questions and problems, a bibliography, and an index. The bibliography is fairly short; the index appears to be quite adequate. Descriptive Statistical Techniques for Librarians is a well conceived, clearly written introduction to a number of descriptive statistical techniques which should be familiar to most librarians. Though a bit skimpy in places, the text generally does a good job of defining and explaining basic terms and techniques. The work is not overly ambitious, i.e., the author does not attempt to cover the waterfront of statistics in one small book. Nor does the work require that readers have any previous background in statistics, though the author does assume a “familiarity” with algebra. This textbook, which appears to be a substantially revised and expanded version of an earlier work by Hafner,’ is recommended for those wanting a succinct, generally nontheoretical introduction to basic descriptive statistics. Readers desiring some additional background in statistical techniques may wish to refer to books by Jaeger and Rowntree.’ REFERENCES 1. Hafner, A.W. Descriptive Statistics for Librarians. Chicago: Midwest Health Science Library Network, 1982. 2. Jaeger, R.M. Statistics; A Spectator Sport. Beverly Hills, CA: Sage Publications, 1983. Rowntree, D., Statistics Without Tears; A Primer for Non-Mathematicians. New York: Charles Scribner’s Sons, 1981.
School of Library and Informational University of Missouri-Columbia Columbia, MO
Science
RONALD R. POWELL
Guide to the Evaluation
of Library Collections. B. LOCKETT (ED.). Subcommittee on Guidelines for Collection Development, Collection Management and Development Committee, Resources Section, Resources and Technical Services Division, American Library Association, Chicago (1989). v + 25 pp., $5.00, ISBN 0-8389-3370-X.
This book is the second in the series of Collection Management and Development Guides published by the Resources Section of the Resources and Technical Services Division of the American Library Association. It combines the evaluation section of Guidelines for Collection Development, edited by D. L. Perkins (1979), and “Guide to Collection Evaluation through Use and User Studies” by D. E. Christiansen et al., published in Library Resources and Technical Services 27 (1983). The guide’s purpose is to provide a statement of principles and methods by which a library can determine the extent to which it satisfies its users and fulfills its stated mission by acquiring the needed books, journals, and other materials. Meant as a checklist of possible methods, the guide is brief, totaling 17 pages of text. In outline format, it lists methods of evaluation, the types of libraries for which they can be used, and the advantages and disadvantages of each. The methods, broadly divided into those that are collection-centered and those that are user-centered, are not described in detail. For further information, the reader is referred to the guide’s extensive bibliography, which is organized by evaluation methods (e.g., circulation studies, citation studies, conspectus format, interlibrary loan, user surveys). The guide identifies its intended audience as those who practice collection development, administrators, collection development officers and policy makers, and accreditation committees. While the guide might be too elementary for some practicing professionals in this area, it would be quite useful for library school students and professionals new to collection evaluation. Its authors acknowledge that the methods listed are “heavily slanted to books and periodicals, although methods for other information formats are included when they exist.” In this respect, the guide seems behind the times, as libraries increasingly obtain access to information in nonprint format and through resource sharing. Nonetheless, it provides a succinct and valuable overview to the range of methods available and the limits of their usefulness. The guide does not identify the first in its series (Guide for Writing a Bibliographer’s Manual, ALA, 1987), but does indicate that the next will be Guide for Written Collection Policy Statements. Perhaps this coming guide will give nonprint sources the prominence they deserve. School of Library and Information Catholic University of America Washington, DC
Science
JEAN L. PREER