FROM THE BOOKSHELFANDREW RUPPEL,
Feature Editor,
McIntire School of Commerce, Global Searches, Global Modelsby Andrew Ruppel, McIntire School of Commerce, University of Virginia The World Wide Web offers the searcher/ browser some, but not enough, useful information about books of interest to decision scientists. After several sessions of search engine application and URL chasing, the following sites were uncovered. The presentation below will go from the general or directory-type sites to those that are more publisher or topic specific. One overview list uncovered is at: www.edoc.com/ejournal/publishers.html. There are over 630 entries combined in the six categories presented on this page (see Figure 1). Clicking on the Academic Publishers category sends one to a roster of about 60 entries, many of them university presses. A staffer at Vanderbilt University's library maintains a list of publishers and vendors that exceeds 1000 items. Alphabetic groupings and subject divisions are provided to aid in locating a publisher. The address is: http://www.library.vanderbilt.edu/law/acqs/ publ.html. Wake Forest University's Babcock School site: http://www.mba.wfu.edu/B2B/publishers.html offers a guide to academic textbook publishers as part of its Business to Business marketing exchange. Only fourteen are listed and among the missing business book publishers are Irwin and West, both of which have their own URLs (see below). Since things on the Web seem to change by the minute, by the time this column appears in print, new entries are likely to have appeared, as well as some sites to have disappeared or relocated.) Of course, various academic departments, authors, and journals are making their papers and articles available on the Web, some in full-text form, some in bibliographies, and some in citations on the occasional personal vitas that crop up in search results. One interesting site in Australia is at the Department of Mathematics, University of Melbourne. This group claims credit for hosting WORMSþworld operation research and management science network. They also offer a virtual ORMS library. Their web address is: http://www.maths.mu.oz.au/~worms/. Book reviews, per se, of interest to decision scientists are very hard to find on the Web. Reviews of books in literature and the humanities readily appear, however. Some of these can be found by starting at: http://www.bookport.com/welcome/commons/ ibfhome. Among the publishers (who produce books of interest to decision scientists) with their own web sites are: http://www.mot.com/Motorola University/ (for Motorola University Press) http://www.thomson.com (for boyd & fraser, Course Technologies, Inc., South-Western) Given all of this, what advice do I offer DSI members looking for book information on the Web? Clearly it depends upon what search terms or clues you're starting with. If you have the publisher's name, then a good start is to try it in the form: www.name.com. If all you have is an author or title, then use one of the spiders, which is netspeak for search engines. Two spiders that I've found effective in general are Lycos.com and altavista.digital.com. Both offer simple and advanced ways to compose a search. The default search engine that comes on the Netscape button bar is Yahoo.com. It offers subject groupings of book publishers, but those for business and economics are simply not complete enough to warrant using. I'd appreciate hearing from readers who have uncovered Web sites of interest to DSI members and who have developed their own search tricks. My e-mail address is acr2y@virgina.edu. My Web page is at http://poe.acc.virginia.edu/~acr2y/. Moving from global searches for books on the Web, here's my review of a useful book about global models.
by Joel E. Cohen Norton, 1995, 532 pages While the title of this work lacks an academic ring, the manner in which the topic is handled by the author is definitely scholarly and objective. Why should decision scientists read it? Because it clearly addresses basic decision-science topics. These topics include: model building, model testing, revision, constraint incorporation, data collection, parameter estimation, scenario creation, systems modeling, sensitivity analysis, acknowledging value judgments, and communicating findings. It covers all the bases in focusing on one central question, ``What is the population carrying capacity of the planet?'' The book is highly recommended reading for graduate courses in model building. The author's intellectual credentials are formidable. Holder of two Harvard doctorates (one in applied math, the other in population sciences), Cohen heads the Laboratory of Populations at Rockefeller University. A McArthur Foundation award winner, Cohen is the author /coauthor/coeditor of seven other scientific volumes. His book offers not only a macro-history of global population growth , but also a history of the efforts to model that growth. The book's eighteen chapters are divided into five parts and are buttressed by six appendices, plus an extensive set of end notes and a lengthy bibliography of some 600 entries. The appendices run close to 150 pages in total and provide not only chronological tabulations of quantitative and qualitative statements of how many people that the earth can support, but include an attempt to model the ideas of Malthus and Condorcet. (Carrying out a critique of this attempt would make a good doctoral written exam question.) Despite the high scholastic caliber with which the book is assembled, it is written more for a general, college-educated audience than for fellow demographers. The writing style is, at times, conversational and clearly the author wants to keep his reader engaged in the material. For example, in dealing with population problems, the author describes three approaches: bigger pie; fewer forks; better manners. Part 1 provides the introduction. The author presents some ancient texts and contemporary examples to illustrate the concern for overcrowding. He presents his aim as one of facilitating population problem-solving, rather than one of sounding an alarmist cry. He shows the difficulty of comprehending large numbers of people and the difficulties in compiling accurate measures of such numbers. Says Cohen: In demography, the shadow of uncertainty is often longer than conceded. Of the book's five parts, the ones of greatest interest to decision scientists would be three and four. In Part 3, Cohen examines three broad methods for projecting population numbers. Of these, he favors the cohort-component method of estimating population growth and places heavy emphasis on the explicit statement of assumptions. Cohen shows how well-known, s-shaped curve-fitting techniques built around exponential growth are an inadequate method for judging limits. (Readers interested in the field of technological forecasting will find this section familiar.) And he shoots the systems dynamics based-methods spawned by the work of Jay Forrester out of the water. Its flaws are seen not so much as flaws of design as flaws of data. His own Law of Prediction goes as follows: The more confidence someone places in an unconditional (meaning no conditions are identified) prediction of what will happen in human affairs, the less confidence you should place in that prediction. If a prediction comes with an estimated range of error, the narrower the range, the less you should believe it. Cohen generally seems to feel that the number of factors involved in social systems are too many, and their interactions too complex, to permit predictions of high accuracy, particularly with regard to birth rates. ``Do we known anything for sure about future population?'' he asks in a short Chapter 9. His answers: it's uncertain, it has momentum, but zero global population growth will occur at some point (though we might not recognize it at the local level). Part 4 shifts the question from ``How many people might there be?'' to ``Is there enough for everyone?'' It might surprise you to learn that the Dutch scientist Leeuwenhoek was apparently the first to address the carrying-capacity question. Cohen provides the summaries of over 65 other estimates of the earth's potential carrying capacity in Appendix 3, and in Chapter 11 he weaves them together to form a historical as well as scientific picture. The estimates range from a low of 1 billion to 1000 billion (current global population is on the order of 5.6 billion). The modal value for carrying capacity is somewhere between 8 and 16 billion. In addressing the question of constraints, Cohen recognizes that some authors focus on a single resource constraint (e.g., water), some focus upon multiple constraints that can be reflected in a single dimension (e.g., land or energy), while other authors tackle the job of addressing multiple, independent resources. Cohen devotes a whole chapter to the question of water supplies, but in the case of multiple natural resource factors, he argues that what unites them in their impact on humans is time. Time, that is, to understand and to apply ingenuity to each resource problem. That ingenuity may be eroded by excessive resource scarcity and the concomitant societal turmoil, Cohen indirectly suggests. In addition to the earth providing the necessary carrying capacity, humankind will need to provide sufficient caring capacity as well, he concludes. Many of the calculations and figures (60 in all) in this book were developed by the author on a personal computer. Among the many interesting figures are: the author's attempt to confirm the staircase model of E.S. Deevey, Jr.; the convergence of high-low predictions for the 1980 population level; and the rocket-launch-like plots of population growth since the last ice age. While eschewing the notion that population dynamics is a simple issue, the author nevertheless shows that supercomputer technology is not needed to develop conditional predictions and the unfolding of scenarios. Students will readily come away from this book feeling they can carry out the analysis of complex issues without having to resort to excessively complex methods.
Dr. Andrew Ruppel |