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Circle No. 73 on Readers' Service Card

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shown a significant correlation withmortality. However, oxidant is also cor-related with CO (P < .00001) butshowed no association with mortalitywhen substituted for CO or when addedto the regression with CO. Our atten-tion was directed to CO in preferenceto other primary pollutants because itis present in concentrations known toaffect oxygen transport in the body.But we agree that NO, NO,, sulfurdioxide, and the meteorological vari-ables cited by Ellsaesser and othersshould be examined.Minimum temperature can be ruled

out; when substituted for maximumtemperature in our regressions the meansquare for residuals (MSE) and t forthe CO coefficient were increased.Mean temperature gave a small de-crease in MSE and in t, but this doesnot affect our conclusions.

Ellsaesser questions the consistencyof our statement concerning reductionin variance with Table 1. The R' inthe table is the ratio of the regressionsum of squares to the total sum ofsquares, here 163,895/441,313 = .3714.The reduction in variance for the re-gression is (302.27 -191.98)/302.27= .3649. These differ because MSE, amore conservative measure, takes intoaccount the reduction in degrees cffreedom resulting from the additionof terms to the regression.

Ellsaesser emphasizes that the modelwithout CO "'explains' only" 0.4 per-cent less of the original variance thanthe model with CO. As stated in ourreport, the estimated contribution tomortality for Los Angeles County as-sociated with CO may be a differenceof as many as 11 deaths in one day,all other factors being equal. We donot think that contribution is trivial.

Ellsaesser is correct in stating thatone would expect the regressor vari-ables to "explain" a greater percentageof the original variance if the Fouriercomponents of the dependent variablewere not removed. But cyclic variableswith the same periodicity will exhibita nonzero correlation even if other-wise totally unrelated. To avoid thisspurious association it was necessaryto add Fourier terms to the regression.Otherwise, daily mortality in Los An-geles, uncorrected for the cyclic com-ponents, would be expected to exhibita highly significant correlation withCO concentrations in Paris, hog pricesin Quebec, maximum temperatures inBuenos Aires, or similar cyclic phe-nomena.

The observation that the mortality

rate may have declined during thetime that CO levels were increasing iscorrect but irrelevant. Analysis basedon rates is both unnecessary and im-possible-impossible because the re-quired denominator data, classified byage, race and sex, are not available be-tween census years, and unnecessarybecause analysis of the relationship be-tween CO concentration and total mor-tality does not require knowledge ofthe denominator. We included trendterms to allow for population growth,changes in population structure, andsecular changes in mortality. From thenature of regression analysis the trendterms provide a close fit at the begin-ning and end of *the study period.Analysis of residuals for the modelwith trend, cyclic variation, and tem-perature removed showed no signifi-cant serial correlation, and a nonpara-metric test for fit (tho "runs" test) wasalso negative. This indicates that nosystematic deviation, such as wouldbe caused by inadequate allowance forpopulation changes, is present.

Ellsaesser suggests that automobilefatalities might be the source of theassociation. We looked at specificcauses using the same regressions and.found that most of the excess mor-tality is attributable to cardiovasculardisease. The association of CO withautomobile fatalities is actually nega-tive; this is predictable, since CO con-centrations are lowest on weekendswhen automobile accidents and fatali-ties are highest, although other factorsalso contribute.

With regard to Ellsaesser's final com-ment, perhaps we did not make ourprocedure sufficiently clear. We did in-deed test a number of models beforearriving at the regressions shown inouLr report. However, the testing was

done before adding the CO and oxidantvariables. The second of the threemodels shown provides an estimate ofdaily mortality which may be used inother applications of interest to us; de-velopment of this model gave us theopportunity to test CO and oxidantwith little additional effort. We cer-

tainly had grounds for suspecting thatCO and oxidant contribute to mor-

tality. We found our suspicions con-firmed for CO but not confirmed foroxidant.We are well aware that demonstra-

tion of an association does not provecause and effect. However, the maxi-mum daily average for CO concentra-tion observed in our study, 20 ppm, issufficient to convert at equilibrium ap-

SCIENCE, VOL. 173

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Their conclusions are publishedin two volumes. Volume I, a con-cise overview, relates their find-ings to public policy on popula-tion growth and makes specificrecommendations for future popu-lation control. Volume II containstechnical papers on all aspects ofpopulation from resource ade-quacy to health care, education,family size, and political demog-raphy.

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Cirde No. 75 on Readers' Service Card

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proximately 3 percent of the bloodhemoglobin to carboxyhemoglobin,with reduction in the oxygen-carryingcapacity of the blood. Since the pollu-tant data are basin averages, some in-dividuals were exposed to substanti-ally higher levels.

ALFRED C. HEXTERJOHN R. GOLDSMITH

Californiia State Department ofPlublic Health, Berkeley 94704

American in Japan

I have just returned from my 20thor so trip to Japan to find on my deskChalmers Johnson's review (5 Feb.,p. 467) of my book The EmergingJapanese Stuperstate. . . . It seems tome that I am almost obligated to quoteand comment on one remarkable andcharacteristic paragraph of the review(italics are mine). "This book seems tobe inspired by Kahn's two visits to Japanduring which he gave lectures atKyoto-Sangyo University (which he ap-parently does not know is more of aJapanese Rand Corporation than auniversity) and where he had severalmeetings of several members of onesegment of the Japanese establishmentwho understandably were quite pleasedwhen Kahn went homne and wrotedown what they told him without do-ing any further checking."

1) I have been making about two orthree trips a year to Japan since 1965.Each of these trips was for the dualpurpose of information gathering andinformation giving and, as a result, Ihave had a great deal of contact withevery aspect of Japanese society, in-cluding students, laborers, union offi-cials, all the political parties, and so on.

2) Kyoto-Sangyo University is a uni-versity. It has none of the character-istics of a "Japanese Rand Corpora-tion" other than those any universitymay possess. I happen to be (alongwith Arnold Toynbee, Raymond Aron,and Hubert Humphrey) a member ofits academic advisory board and havebeen at the university many times.

3) As is clearly pointed out, the firstchapter of the book summarizes notonly the talks I gave at Kyoto Univer-sity but also the argumentation in thebook. It would not have been possibleto get this argumentation from whatwas then my audience.

4) . . . As I also bring out in thebook, we did a serious study in themid- 1960's on long-range Japaneseprospects. The argument of the book

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SCIENCE, VOL. 173

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is largely based on that study and waspublicly presented and discussed, ratherthan derived, during my later visits toJapan, during which I gave the twotalks at Kyoto-Sangyo University. Thisis a matter of public record as well asbeing discussed in the book. Johnson'scharge thit I "went home and wrotedown what they told [me]" sheds morelight on his review than on the book.

Johnson is correct that the DodgePlan currency reform was made in1949, not 1951, but this slip makes nodifference to any of my arguments. Ibelieve that my statement that MissKamba was the only person killed inthe Japanese student riots was correctat the time I wrote it, although it is nolonger correct. The information camefrom members of the Japanese police,but none of the students with whom Italked contradicted it (and many ofthem would have liked to)....

HERMAN KAHNHudson Institute,Croton-on-Hudson,New York 10520

Pavlov's Film

At the 14th International Congressof Physiology in Rome in 1932, Ivan P.Pavlov projected a film on "The Func-tion of the Brain." After the congressPavlov donated the film to my father,Carlo Foa, who was professor andchairman of the department of physiol-ogy at the University of Milan, and heused the film for many years. Upon myfather's retirement, I brought the filmto Detroit where, in collaboration withErnest A. Gaynes and Robin A. Bar-raco, it was translated into English andtransferred onto 16-mm safety film.The potentially explosive 35-mm origi-nal nitrate film was destroyed in com-pliance with fire and safety regulations.The film, black and white and silent,may appear elementary and sometimesrather naive by 1971 standards. How-ever, it is of great historical interestbecause it depicts some of Pavlov'sbasic experiments on conditioned re-flexes and some of his observations ofbehavioral development. The completefilm lasts approximately 21/2 hours, buttwo shortened versions with projectiontimes of 45 and 60 minutes have beenproduced. I will provide further infor-mation upon request.

PIERO P. FOADivision of Research, Sinai Hospitalof Detroit, Detroit, Michigan 48235

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Circle No. 78 on Readers' Service Card

658

Maya Classic way of life in the south-ern lowlands. Only a few very minorcenters, such as the ones at Lake Petenand Lake Yaxha, date from the Post-classic period, but these are poor in-deed compared to those of the Classic.For the most part, the area remainedabandoned or drastically depopulatedand culturally reduced. In Yucatansome significant new centers did springup, undoubtedly attracting trade mer-chants, craftsmen, and peasants; how-ever, the more important centers of thePostclassic period lay outside the Mayalowlands altogether. In effect, the Mayalowlands had been bypassed by theprogress of Mesoamerican civilizationWhose main course was then firmly setby the social and political order of thenew type that was propagated fromcentral Mexico (3).

GORDON R. WILLEYDepartment of Anthropology,Harvard University,Cainbridge, Massachusetts 02138

DEMITRI B. SHIMKINCenter for Advanced Study in theBehavioral Sciences,Stanford, California 94305

References and Notes

1. For general introductory but authoritativeworks on Maya archeology the reader mayconsult J. E. S. Thompson, The Rise and Fallof Maya Civilization (Univ. of OklahomaPress, Norman, ed. 2, 1966) and M. D. Coe,The Maya (Praeger, New York, 1966).

2. Maya Long Count or Initial Series dates arerendered into the Christian calendar by twoprincipal correlations. The one most generallyfavored, and used throughout this summary, isknown as the 11.16.0.0.0 or Goodman-Martinez-Thompson correlation. The 12.9.0.0.0 or Spin-den correlation would place all the dates citedas 260 years earlier.

3. Participants of the symposium were T. P.Culbert (University of Arizona, organizer), G.R. Willey (Harvard University, chairman), R.E. W. Adams (University of Minnesota), E.W. Andrews IV (Tulane University), W. R.Bullard, Jr. (Florida State Museum), J. A.Graham (University of California, Berkeley),R. Rands (Southern Illinois University), J. A.Sabloff (Havard University), W. T. Sanders(Pennsylvania State University), D. B. Shim-kin (University of Illinois), and M. Webb(Louisiana State University, New Orleans). Afull report on the proceedings, including aseries of data papers and a lengthy summaryof the discussions, will be published in thenear future as a monograph of the School ofAmerican Research.

Forthcoming Events

September

8-10. Design Automation, intern. conf.,Toronto, Canada. (A. Seireg, Dept. of Me-chanical Engineering, Univ. of Wisconsin,Madison 53706)

8-10. Pharmacology of AntiepilepticDrugs, Scottsdale, Ariz. (J. K. Penry,Bldg. 36, Room SD-10, NatI. Inst. ofNeurological Diseases and Stroke, Bethes-da, Md. 20014)

8-10. Society of Therapeutic Chemistry,8th intern., Lyon, France. (H. Pacherco,Service de Chimie Biologique, INSA 20Ave. Albert Einstein, 69 Villeurbanne,Lyon)

8-10. Urban Transportation, 5th intern.,Pittsburgh, Pa. (A. V. Harris, PittsburghUrban Transit Council, U.S. Dept. ofTransportation, Transportation ResearchInst. of Carnegie-Mellon Univ., P.O. Box2149, Pittsburgh 15230)

8-11. Drugs Affecting Lipid Metabo-lsin, 4th intern. symp., Philadelphia, Pa.(W. L. Holmes, Lankenau Hospital, Lan-caster and City Line Aves., Philadelphia)

8-11. International Assoc. of Gerontol-ogy, Bern, Switzerland. (B. Steinmann,Medizinische Abteilung C. L. Laury-Haus,Inselspital Bern, 3008, Bern)

8-12. National Conf. on MechanicalVibrations, 3rd annual, Toronto, Ont.,Canada. (P. W. Curwen, Mechanical Tech.Inc., 968 Albany-Shaker Rd., Lathan,N.Y. 121 10)

8-15. Illumination. 17th intern. conf.,Barcelona, Spain. (Secretary, Intern. Com-mission on Illumination, 25 rue de laPepiniere, Paris 8e, France)

9-10. Aerospace Mechanisms, 6th an-nual symp., Moffett Field, Calif. (G. G.Herzl, ORGN. 52-60, Bldg. 201, Lock-heed Missiles and Space Co., 3251 Han-over St., Palo Alto, Calif. 94304)

9-11. Cardiovascular Soc., 10th intern.,Moscow, U.S.S.R. (A. D. Callow, 171Harrison Ave., Boston, Mass. 02111)

9-ll. American Assoc. of Obstetriciansand Gynecologists, Hot Springs, Va. (C.A. Hunter, Jr., Indiana Univ. MedicalCenter, 1100 W. Michigan St., Indianapo-lis, Ind. 46202)

9-11. Parapsychological Assoc., 14th,Durham, N.C. (J. G. Pratt, Box 152, Uni-versity of Virginia School of Medicine,Charlottesville 22901)

9-11. Photosensitization in Solids, 3rdintern. conf., Sarlat, Dordogne, France.(J. Bourdon, Centre de Recherches Kodak-Pathe, 30 rue des Vignerons, 94 Vin-cennes, France)

9-15. Union of Prehistoric and Proto-historic Sciences, 8th intern., Belgrade,Yugoslavia. (A. Benac, Archeoloski Inst.,Knez Mihajlova 35-11, Belgrade)

10-12. International Soc. of Hematol-ogy, Milan, Italy. (A. T. Maiolo, Istitutodi Pathologia Medica, Via Pace 15, 20122Milan)

10-12. Pollution and Conservation ofthe Seventh Continent, Antarctica, Blacks-burg, Va. (B. C. Parker, Dept. of Biology,Virginia Polytechnic Inst. and State Uni-versity, Blacksburg 24061)

12-15. Canadian Agricultural Chemi-cals Assoc., 12th annual, Montreal, P.Q.,Canada. (J. Chevalier, Suite 1004, 1010Ste. Catherine St., W., Montreal)

12-15. Ceramic-Metal Systems Div.,American Ceramic Soc., St. Louis, Mo.(Secretary, ACS, 4055 N. High St., Co-lumbus, Ohio 43214)

12-16. American Assoc. of BloodBanks, Chicago, Ill. (L. J. James, 30 N.Michigan Ave., Chicago 60602)

12-17. American Chemical Soc., 162ndnatl. fall mtg., Washington, D.C. (F. T.Wall, ACS, 1155 16th St., NW, Washing-ton, D.C. 20036)

SCIENCE, VOL. 173