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the book (about 320 pages). Chapters are well-sprinkled with applications illustrating ortho effects, substituent additivity effects, the effect of location of substituent, the determination of new σ values, and the factors affecting the reaction constant p.

The first part of the book (about 40 pages) is introductory in nature. In this section no attempt is made to cover general polarographic theory or instrumentation. It does, however, emphasize the important experimental conditions required for obtaining polarographic data that are useful for correlative purposes. In the same re­spect the author has assumed that the reader has reasonable knowledge of substituent properties common to the physical organic area such as polar effects, resonance effects, steric effects, and their combined effects. Introduc­tion to these areas from a general point of view is covered very briefly.

The book is designed to be a refer­ence text in organic polarography. Most important is that it carefully illustrates how to use the polaro­graphic technique to study mecha­nisms, course of electrode reactions, and structural effects in organic reac­tions. Other possible studies included are the detection of deviations in mechanisms, the comparison with equilibrium or rate constants or other physical quantities, and prediction of data for new or unstudied substituted organic compounds.

The book is generally free of errors of omission (or typographical ones). A few noticeable ones are on page 37, line 5 and page 266, line 7 in section 6. Structure (I) on page 30 is in error. A very difficult task for the author must have been the arranging of all of the data in the many figures and tables. The author's and publisher's efforts have resulted in easily read and clearly defined figures and tables. Only in Figure VII-2b was it unclear as to where substituents were located on the organic molecule. For the most part experimental conditions used in collecting the polarographic data are included in the tables (Table IX-6 is an exception) and if the reader requires further information, he can consult the conveniently listed references.

The author makes no effort in his discussion on organic substituent ef­fects to describe or list correlations of polarographic data to spectral data, to theoretical calculations, or to ioniza­tion potentials. Possibly the author will take up this interesting subject in a future book. One other minor short­coming is that more emphasis and dis­cussion might have been placed on completely nonaqueous systems.

Anyone interested in organic polar­

ography will find this book to be a valuable addition to their library. Other chemists will find it to be a useful source of polarographic data while those chemists interested in mechanisms of organic reactions and the effects of substituents will find it to be an excellent discussion about the use of the polarographic technique for these kinds of studies.

Prediction Analysis. John R. Wol-berg. xi + 291 pages. D. Van Nostrand Co., 120 Alexander St., Princeton, N. J. 1967. $10.75. Reviewed by Donald G. Watts,

Department of Statistics, University of Wisconsin, Madison, Wis. 53706.

I find it somewhat surprising for a physicist to write a "cook book," which is about what "Prediction Analysis" is. To this extent though, the author is successful since the purpose of the book is to help engineers and scien­tists plan their experiments.

By the author's definition, "Pre­diction analysis is a technique that can be used to facilitate the planning of quantitative experiments," and " . . . is a general method for predicting the ac­curacy of results that should be ob­tained from a proposed experiment." It consists, essentially, of 1) specify­ing a parametric model for the experi­ment, complete with "error" terms (random variables), 2) specifying the necessary parameters to describe the error random variables, 3) deriving expressions for standard deviations σα of the parameters in the model in terms of the error random variable standard deviations σχ, 4) "guestimat-ing" values for the a-x's and hence ob­taining "predicted" values for the aa's, 5) using the predicted CTa's to decide the feasibility of the experiment, whether the results will be good enough, what error terms must be reduced, if possible, and so on. This approach will probably appeal to physicists, but chemical engineers and others who deal with less well-defined situations may find it difficult or impossible to apply.

The book purports to be self-con­tained, for example "All essential back­ground material in the areas of sta­tistics and the method of least squares is included in Chapters 2 and 3." The material in these chapters lacks clarity, however, not only from lack of rigor, but also because of poor exposition. For example, Figure 2.1, page 11, shows "A typical frequency distribution for a discrete random variable" which re­sembles a histogram with all values between 1.5 and 5.5 possible! On the same page is the statement "The 'mean' is the average value of x." And on page 15, "A confidence interval is defined

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