A Statistical Manual for Chemists (Bauer, Edward L.) - Journal of

A Statistical Manual for Chemists (Bauer, Edward L.) Lloyd S. Nelson. J. Chem. Educ. , 1961, 38 (1), p A46. DOI: 10.1021/ed038pA46. Publication Date: ...
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A Statirlieal Manual fol$hernids

Edward L. Bauer, Winthrop Lttboratories, Reneselsrer, New York. Academic Press. Inc.. New York. 1960. x 156 pp. I&. &d tables.' 14 X 21 cm. 84.75.

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It is being increasingly rccagniaed that modern statistics provides the chemist with a sharp tool of wide applicability. Several hooks have appeared in whioh statistics is presented via chemical examples. "A Statistical Manual for Chemists" by E. L. Bauer is the latest addition to this group. The author prefients a sub-elementary rtnd very limited view of statistical methods. The comparison of two and of more than two averages, some of the elements of experimental design, regression, sampling, and the use of qualit,>,control techniques in the analytical laboratory are mentioned. The hook concludes with a collection of nine tahles d e s b e d to provide the necessary crit,ical vslues for the techniques propounded. Virtually all of thc procedures described employ the range as sn estimator of thc population standard deviation in place of the conventional standard deviation estimate. Unfortunately, however, t h e reader is not given any basis for evaluating the author's statement (p. 11) that ". the range is accurate enough for practical purposes." (Actuall.y, efieienef, rather than accuracy is in question.) Although range techniques have their place, the same information concerning variability is obtained from nine oh~ervationswith the range aa from eight observations using the standard deviation estimate. By increming the ~ t a t i s t i c d work in that eight numbers must be squared, one can cut back the experimental work by a little more than 10 per cent. The choice should he the experimenter's. Nevertheless, even granting that the author hss made an appropriate decision ior the experimenter in regard to the use of the range, this book must be severely critieieed far the many misleading phrases and numerous incorrect statements it contains. Hypotheses, tests of significance, confidence intervals, multiple comparisons, and regression andvsis are taken up by the author. Within every one of these topics there are glaring mistakes of either explanation or interpretation. Inconsistent terminology adds t o the confusion. Experimental design is discussed but the term interaction is not fully explained and the suhjeot of randomization (essential in st.atistics) is by-passed completely. Thc dist,inction, which is of fundamental importance, between a statisticel parameter and a. statistic (a value which estimates B parameter) is not medq clear. The reader is not shown the central role played b y the null h y p t h e s i ~in significance testing; nor is he given any inkling that hypothesis testing is not limited t2 zero-difference null hypothenes. On page 17 confidence intervals (incorrectly dcscribed) sre wrongly interpreted as tolerance intervals. The uncertainty calculated far the

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predicted value obtained from t,he regression ansl,vsis on page 103 i8 too small by a factor of 30. The procedure which the author should have followed is clearly outlined in the second reference given on that same page. On page I34 the normd dist,rihotion is described as having 2:i per cent of its area and 5 per cent of its area ahove points one and two standard deviations up from the meen, respectively. Bath of t h e ~ evalues are quite wrong, but the reader u-ill have to check this fact elsewhere because this hook does not hnve a tnhle of the normal distribution. Tho preceding criticisms ar? only 3. small sample of what is nrong with this book. Anyone attempting to learn the subject of statistirs or an," part of it with the aid of this mrmr~nl\\-ill l,r getting off to a very had start. LLOYD S. XELSOR General Eleclvie Lamp Divisivn Clezwland 1 % Ohio Optical Rotatory Dispersion: Applicalions to Organic Chemistry

Cad Djrrassi, Stanford University, California, and Rymtes (S. A,), Mexico City. MeGraw-Hill Rook Co., Inr., SPW York, 1960. xiii 293 pp. Figs. and tnhle. 15.5 X 23.5 cm. 37.50.

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I t has been a long time since P. A. Levene and Alexandre Rothen wrote their chapter on "Rotatory Dispersion" for the fivst edition of Gilman's "Organic Chemistry, a n Advanced Treatise," to which most graduate students in chemistry have been exposed a t least in part. Xewer npplieations and the recent accumulation of reported research have made it desirable modern treatto hnve an a~~thoritative ment. This is edited and largely written by Carl Djerassi of Stanford Univemity under the title of "Optical Rotatory Dispersion." Other writers who have contributed substantially are Albert Moseowit,~,the late William Moffitt, Elkan R. Blout, and John A. Sehellman. The book opens with a preface telling of the necessity to undertake such a writing because of the gap since the publication of T. M. Lowry's "Optical Rotatory Parer" i n 1934. There follow^ seventeen chapters beering the titlea: Introduction; Nornenrlnture; Instrumentation; Storaids: Biryrlic Ketones; Triterpenoids; Monocyclic Aliphatic Carbonyl Compounds; ~ H y d r o x yKetones; --Halo ketones; DPterminat,ion of Absolute Configuration; Detertion and Implication of Ketnl Formation; Themy and Analysis of Rotatory Dispersion Curves; Oetant Rule; Thiones, Xitroalkanes, and Other Chromophores; Blcohols; a-Hydroxy Acids, and --Amino Acids; Plain Dispersion Curves; Polypeptides and Proteins. There are two appendixes: .4. Bibliography, with a concise review of earlier literature, a.concise review of later lit,erature and sn extensive list of publications of Carl Djerassi; B. Nomew clature and Stereochemiral Conventions, with reference to Steroids and Triterpenoids. Author and compound indexes are supplied. Tables, graphs, formrdas, and diagrams are used effectivdy and clearly throughout the chapters. (Continued on page A501

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