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Home , Wassily Leontief

current comments” EUGENE GARFIELD INSTITUTE FOn SCIENTIFIC INFORMATION* 3501 MAR KETST PHILADELPHIA PA 191Ck4

Wassily Leontief: I Pioneer of Input- Analysis

Number 37 September 15,1986

“It is a mistake,” observed that civilian honor in 1984. These are only master logician Sherlock Hohnes, “to two of the many awards he has received theorize before one has data.”1 for hk contributions to economics. With this working principle Over the years I have had relatively lit- Wassily Leontief would surely concur. tle professional contact with econa For Leontief, currently University mists. , a pioneer in the Professor at ’s In- economics of information and the idea stitute for Economic Analysis, explana- of intellectual capital, was one excep- tions of economic systems must be tion.z The work of Leontief, however, grounded in facts. Theory follows as an has been recommended tome frequent- instrument that helps explain facts. ly. Many colleagues in the social Leontief’s dedicated preference for what sciences, including the sociologist can be observed rather than what can be Robert K. Merton, Columbia Universi- imagined, coupled with an insistence on ty, urged me to make his acquaintance. practical applications, led him to his They alf rightly anticipated that Leon- greatest achievement—the invention tiefs input-output technique could have and elaboration of input-output analysis practical application in information (IOA). science, and so it has.~s Unaware that I In the hands of Leontief and his many was doing so, I have been using a type of students and followers, the tool of IOA input-output methodology in my cita- has shaped our knowledge of how and in tion analyses of journals and in ISP’s what measure the constituent parts, or annual Journal Citation ReportP. It was sectors, of an interact. More Merton in particular who saw the con- than a tool of analysis, it can also reveal nection between Leontiefs technique what combination of resources (raw and our analyses. We now plan to use material, labor, capital)—called in- Leontiefs matrix structure, in an essay puts—is required to achieve desired prm next year, to present data on the “stocks duction goals—called outputs. IOA, and flows” of citations in and among therefore, plays a central role in plan- economics journals. ning and even in prediction. Today, It was not until early May of thk year, more than 60 nations and countless however, that I met Professor Leontief. businesses construct input-output tables We met at one of his favorite restaurants to guide them in making economic deci- in New York, on the north side of Wash- sions. ington Square, not far from his office at In recognition of the importance of the institute. IOA, Leontief was awarded the Nobel “There is a great difference between Prize in economic sciences in 1973. evidence and inference,” he told me as Japan, the world leader in the use of we began lunch. “I have always looked IOA, presented Leontief with its highest for evidence.”b

272 hand, Leontief, then 22, joined the Insti- tute for World Economics at the Univer- sity of Kiel, where he was engaged in research on problems of supply and de- mand. Adventure intervened. Leontief spent the year 1929 in China as an economic consultant to the Ministry of Railroads. He organized an aerial survey to gather data on agricultural production. This in- formation showed the Chinese govern- ment where to build new rail lines. In an interview with Leonard Silk, Leontief recafled.

I rode on trains that came under fire from bandhs; I remember lying down on the floor. There was fighting in the north with the Russians. The Russian WossilyLeontiej planes bombed the Chinese with wa- termelons. They threw watermelons down on them. This was an idyllic Early Yenrs, Travels, Adventures world, you see. 10 Wassily Leontief was born in Lenin- In 1930 Leontief returned to the insti- grad (then St. Petersburg) on , tute in Kiel, but he was not to remain 1906. His father was a professor of labor there long. His publications, including economics at the University of St. Pe- two articles describing his thesis tersburg. His grandfather owned a suc- work, 11,12attracted attention in the US. cessful textile mill in the city. In 1931 Leontief accepted an offer of In 1921 Leontief entered the Universi- from the National Bureau ty of Leningrad and read the classics of of Economic Research in New York, an political economics, while alf around outstanding research institution organ- him the Russian Revolution was radical- ized by Wesley C. Mitchell. A lecture by ly transforming the economics and Leontief at some few politics of the country. As a noncom- months later brought yet another offer, munist socialist [a Menshevik), he often with further support for his own research and bluntly criticized the new regime, project—a quantitative investigation of and for this he was often jailed. “Some intersectoral flows in the US economy. time in prison, some time at the Univer- He accepted and began KS 44-year sity—it was a good education,” he has tenure as a member of the Harvard remarked.T (p. 8S) faculty. Despite these troubles with the au- thorities, Leontief was graduated from What IsInput-Output Anaiysfs? the University of Leningrad in 1925. Within six months he departed the Sovi- Leontief published the first input-out- et Union for the University of Berlin, put table 50 years ago. is He began th~ where he studied for hk PhD in econom- work shortly after assuming hk new post ics. Leontief published his first article, at Harvard, but it was a difficult under- “The balance of the economy of Russia: taking, and Leontief and his assistant a methodological investigation, ” in needed nearly four years to complete 1925;s it, and his 1928 doctoral thesis, their work. The Economy as a CircularFlo w,~antic- An input-output table is a model of ipated his invention of IOA. Degree in the interindustry relationships in an

273 economy. 14The structure of the table is m 1:Exmde of m input-outputtable(in doflars). a matrix that lists economic sectors, in the same sequence, both vertically and horizontally. On the left-hand side of the table, each row is preceded by the name of a sector; the numbers appearing to the right show where and in what quanti- ty the sector’s output is dispersed. * Sector 2: Across the top of the table, each column Manufacturing I 70 30 150 250 is headed by a sector’s name; the num- Sector 3: - bers appearing below the column head- 80 lao403cm I ing show whence and in what quantity Totsd input 1200250300 that sector derives its inputs. Thus, any sector can be analyzed in terms of the di- (Frum“tn@Output Analysis” by WassilyLecmbef.h hter- &onal Ency&pedia of the Said Sciaxs. David S-. silts, rection and amount of its production or editor.Volume7, p. 346. CopyriS6fa 1%Sby CrowcllColk the origin and amount of its intake. snd Macmifh, fcc Reprintedby permissionof b publisbsr.) A greatly simplified example of an In a recent address before the US Cen- input-output table appears in Figure 1. sus Bureau Conference in Washington, In this example, the economy is defined DC, Leontief used a familiar metaphor in terms of three sectors: agriculture, to describe the special ability of IOA to manufacturing, and households. (Actual bring together micro- and macroec~ input-output tables are drawn up with nomics: hundreds of sectors—the more sectors, It has often been said that in econom- the more detailed the analysis or projec- ics one must make a choice between tion.) The numbers in the table are given detailed description of individual trees in units of (here it is dollars) or aggregative description of the en- but could also be expressed as actual tire forest. Input-output analysis is an units—for example, tons of steel or application of the modern systems ap- kilowatt hours of electricity. In Figure 1, proach that permits us to describe the of the $200 output of the agricultural forest in terms of individual trees. It provides the means for observing and sector, $50 is the intermediate output analyzing simultaneously the quan- that flows back into and is consumed by titative relationships between hun- the agricultural sector, $40 flows to dreds and even thousands of variables manufacturing, and $110 flows to the while preserving throughout all the sector. On the input side, the operations the identity, the name and manufacturing sector, for example, address, of each of them. lb takes in $40 from the agricultural sector, The numbers for Leontiefs first table, $30 from its own sector, and $180 from with 42 sectors, were drawn from the the household sector (a total input of 1919 US Census of Manufactures (the $250) to produce its total output of $250. 1929 census was not yet available when From these actual numbers Leontief the project was begun in 1932). IS None derives coefficients, or ratios, of the knew better than Leontief the many re- quantitative relationship of one sector to finements needed for future input-out- another. The coefficients are fixed by put tables; nonetheless, the achieve- the current technology; by using these ment must have been satisfying: he had coefficients, it is possible to project how united hard data—real numbers-with a changes in input or output of individual theoretical structure and simultaneously sectors will affect all other sectors drawn the “big picture.” because of the strict proportionality as- The idea of constructing a network of sumption for input-output relationships. interindustry flows came to Leontief ear- As technology changes, coefficients ly. As a student he had pored over the change also. 15 classics of political economics in Rus-

274 sian, French, and German. However, he transition from a wartime to a peacetime acknowledges a special debt at the economy, and especially its effect on beginning of his input-output article, IS levels of employment, turned to IOA. and throughout many of hk publica- Leontief served as a consultant to the tions, to the physician-tumed-econo- bureau and, with a small group of re- mist Fran~ois Quesnay and his Tableau searchers at Harvard, constructed a Il?conomique (1758).17 Quesnay, a leader 90-sector input-output table, based on of Physiocratic thought, divided the 1939 data. A second table, with 42 sec- French economy into three sectors tors, was built later and proved its worth (farmers, manufacturers, and landown- as a tool of prediction. Many then ex- ers) and demonstrated how the produc- pected a steep decline in demand for tion of farmers (whom the Physiocrats steel after the war. IOA predicted other- saw as the source of all wealth) was wis+that demand would remain distributed among themselves and the heavy. Few believed this, but that is ex- other two groups in a circular flow. actly what took place as the pent-up de- Another source of inspiration was mand of consumers was unleashed for L~on Walras and his description by durables, such as refrigerators and auto- sophisticated equations of an economy mobiles, that were made from steel. IOA in general equilibrium, in which a had served well, but in the late 1940s balance is struck between supply and de- support from the government fell away. mand. 18Robert Dorfman, Harvard Uni- On this subject Leontief told me, versity, observes that Leontief simplified In this country it is considered some- Walras’s equations to make them “em- what dangerous . . . . Politically, it pirically implementable.” He continues: smells of planning and such things . .. . Whereas Walras had subordinated the [the US] government is most conser- whole question of intermediate , vative in how the economy should be the purchases of the various industries run, or rather, not interfered with. As from each other emerged as the cen- a matter of fact, why should you know tral set of equations in LeontieFs anything about the economy, if the system. What began as a bold competitive system is automaticaffy simplification ended as a basic shift in making adjustments?o the emphasis of the whole system. 19 Input-output research did continue at In 1941 Leontief published a more the bureau, but on a much smaller scale. nearly complete exposition of IOA, with Meanwhile, Leontief received private full theoretical and empirical apparatus, support to establish the Harvard Ece in The Structure ofAmen”can Economy, nomic Research Project, a “laboratory” 1919-1929.20 By this time the US Census with a mission to explore the potential of Manufactures for 1929 was available applications of IOA. In 1953 the group and its data were included. This book published Studies in the Structure of the and its second edltionzl (published in American Economy.zz Leontief con- 1951 and including data from the 1939 tributed four chapters in which he re- census) have received over 175 citations viewed the fundamental concepts of in the Science Citation Inde# (S@), IOA; explored the effects of changes in 1955-1985, and the Social Sciences the technical coefficients, or ratios, Citation @ (SSCP ), 1966-1985 (see from 1919 to 1939; examined the possi- Table 1). bihties of dynamic versus static models (those over time rather than those for a single year); and showed how interre- A Tool of Planning for a gional analyses could be conducted. Tfme of Pfasssshsg Other chapters cover the potential of the During World War II, a division of the input-output paradigm for analyses of US Bureau of Labor Statistics charged capital structure, and final with studying the impact of the eventual demand, aggregation, and specific in-

275 Tabfe 1: Leontiefs works most cited in the SCI, 1955-1985, and in the SSCI, 1966-1985, arranged in descending order according to number of citations. A= total number of citations. B= bibliographic infor- mation, Those items accompanied by an asterisk were reprinted in one of the three volumes listed at the end of the table; the counts for asterisked items do not include citations to reprints of the articles. The identifying numbers of 1983-1985 SC1/SSCI research fronts that include core works by Leontief are given in parentheses after the bibliographic reference.

A B

176 Leontlef W. The strwcture of A men”con economy, 1919-1929. Cambridge, MA: Harvard University Press, 1941. 181 p.; and The structure of American economy, 1919-1939. New York: Oxford University Press, 1951.264 p. 151 Leondef W. The futurw of the wodd economy. New York: Oxford University Press, 1977. 110 p. (830221; 84-8233; 85-6680) 116 Harvard Economfc Research Projeel. Studie$ in the structura of the Amen”can economy. New York: Oxford University Press, 1953.561 p. 109 “Leontkat W. Theoretical assumptions and nonobserved facts. Amer. Econ. Rev. 61:1-7, 1971. (83-4383) 104 “Leontfef W. Environmental repercussions and the economic structure: an input-output approach. Rev. Econ. S(atist. 52:262-71, 1970. (85-6680) 89 “Leontfef W. Introduction to a theory of the internal structure of functional relationships. .Ec0n0mefn2a 15:361-73, 1947. 72 “LeontSef W. Factor proportions and the structure of American trade: further theoretical and empirical analysis. Rev. Econ. Statist. 38:386-407, 1956. 61 ‘Leontfef W. Domestic production and foreign trade: the American capital position re-examined. Proc. Amer. Phil. Sot. 97:332-49, 1953. 40 “Leomfef W & Stmut A. Multiregiorral input-output analysis, (Bama T, ed. ) Structuml interdependence and . Proceedings of an International Conference on Irrput-Output Techrrique$, September 1%1, Geneva, Switzerland. London: Macmiffan, 1963. p. 119-50. 35 Leondef W. Quantitative input and output relations in the of the . Rev. .Econ. Statist. 18:105-25, 1936.

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158 Leontlaf W. Input-output economics. New York: Oxford University Press, 1966.257 p. 32 Leontfel W. Essays in economics. Vol. 1. Theories and theorizing. White Pfains, NY: fntemational Arts and Sciences Press, 1966.252 p. 23 Leondef W. Essavs in economics. Vol. 2. Theories, facts and policies. White Plains, NY: Sharpe, 1977. ~61 p.

dustries (cotton textiles, air transporta- problems: the economic effects of dM- tion). The book has received over 115 ci- armament and military spending,2+zT tations in the SCZ, 1955-1985, and the the costs of pollution,~~ the depletion SSC1, 1966-1985 (see Table 1). of nonfuel mineral resources,31 .32 the A few years earlier, Leontief pub- impact of automation on workers,J>3y lished an article on the basics of IOA in and projections of the world economy to Scientific Amen”can.~ He has consis- the year 200Q.38 This last study was sup tently published articles in this journal ported by the United Nations and was in- and in other publications designed for spired by Leontiefs 1973 Nobel lecture, wider audiences than alone; entitled “Structure of the world econo- he believes strongly in the importance of my outline of a simple input-output for- reaching out to other fields and bringing mulation. “39 The UN study, a massive the results of his labors to the general undertaking, describes a number of pos- pubiic. sible scenarios for the future economic state of the world. In particular, The Sharpening the Tool Future of the World Economy38 shows Since the early 196Qs, Leontief has ap- how and in what measure aid to develop plied his analytical tool to specialized ing countries might be most efficiently

276 distributed. This book has received over He described some of his colleagues to 150 citations in the SC1, 1955-1985, and me as behaving “liie an airplane that the XXX, 1966-1985. It is characteristic took off, is circling, and never lands.”’b of Leontief’s and intellect that, As early as 1937, he questioned the as- in refining and elaborating IOA, he con- sumptions of Keynes’s The Genen.d The- currently sought to analyze and solve ory of Employment, and Mon- practical problems. ey .46-48 A recent book by Ronald E. Miller I already saw what was happening and Peter D. Blair, University of Penn- there. Keynes was demonstrating how sylvania, Philadelphia, entitled Input- one can first provide the formula and Output Analysis: Foundations and Ex- then let someone else make it true. Of course, you can do it. Why not, logi- tensions, is an upto-date review of the cally? But theorizing without facts in current uses and applications of “Leon- an empirical science is very danger- tief matrixes,” as they are often called.@ OUS.6 Leontief has written few books. In his presidential address to the 83rd “Rarely have I written a book to write a meeting of the American Economic book,” he told me. “Usually, I work on a Association in 1970, published a year problem, write an article, and when I later in the Amen”can Economic Re- have enough articles, I publish a book.”b view,@ Leontief systematically criticized Input-Output Economics, published in the profession’s research strategies and 1966,41 is one such book. It gathers to- results. The address, “Theoretical gether Leontiefs most important articles assumptions and nonobserved facts, ” on IOA; this year a greatly enlarged sec- ranks high on Leontiefs list of most- ond edition .appeared.d’2 Other volumes cited works, having received over 100 of collected papers include Essays in citations in the SC1 and SSC1 (see Table Economics, Vohzme 1 and Volume 1). A “journal study” by Leontief, in 2.43,44 These two Volutnes include ar- wh]ch he analyzed the type of methodol- ticles on many topics, including the use ogy used for articles published in the of mathematics in economics, matters of American Economic Review, appeared political economics, and criticisms of in 1982 in Science .45 He found that over Keynesian theosy. half of the articles published by the jour- nal fall into the category of “mathemati- The Trouble with Ecossomics cal models without any data.” The na- ture of Leontiefs entire “output” under- At the beginning of thu essay, I under- scores his firm and long-held opposition scored Leontiefs commitment to empir- to “implicit theorizing, ” and, as he told ical evidence, that is, to facts; he is, me, his commitment “to finding out how however, a master at formulating thee the world works.”b ries and, indeed, throughout his career has taught theoretical economics more often than input-output techniques. He Recent Years seems to emphasize data more than Although now entering his ninth de- theory only because his union of the two cade, Leontief seems to have slackened stands out so sharply against the work of hk pace very little in the search for how many of his colleagues, who, he says, fdl the world works. In 1975, after 44 years page after page of professional ec~ of teaching at Harvard University, he nomics journals.. with mathematical departed for New York University, formulas leading the reader from sets where he assumed the post of professor of more or less plausible but entirely arbitrary assumptions to precisely of economics and, two years later, direc- stated but irrelevant theoretical con- tor of the Institute for Economic Analy- clusions .45 sis. During hk years at Harvard, Leon-

277 tief taught many of the best of today’s This is a special year for Professor economists, including , Leontief. As noted, it is the golden an- , and James Duesenberry. niversary of the invention of IOA. I He called for, as he still calls for, better understand that, later in the year, spe- and more systematic collection of eco- cial sessions on IOA—honoring its in- nomic data in the US. At the institute ventor—will be held at the annual meet- Leontief completed The Future of the ings of the Association World Economy ( 1977),~ and, with and the American Economic Asso- , the institute’s recently ap ciation. 52353 pointed director, Mi[itary Spending: Facts and Figures, Worldwide Implica- tions, and Future Outlook ( 1983).m Last Citation Data year he published, again with Duchin, The Future Impact of Automation on When I told Leontief that we were Wor/cers.51This work predicts a dramat- analyzing the more than 1,500 citations ic shift in the composition of the labor to h~ publications in our database, he force, with fewer clerical workers and said, “Look here: my example [in terms middle managers, but with increased of publications and influence] is very un- numbers employed in producing the new typical. Most of my connections are in technologies. Even under their most ag- other fields.”G gressive scenario for the integration of A survey of 1985 citations to works technology into the workplace, Leontief by Leontief reveals an approximately and Duchin befieve that jobs lost in cler- 40/60-percent split between those com- ical and management areas will be offset ing from economics journals and those by demand for workers in the manufac- from other social-sciences journals, ture of the new technologies. However, respectively. This seems to confirm they conclude that technological unem- Leontief’s view of his own influence out- ployment remains a possibility in the side economics but also indicates no long term. lack of interest in his work by fellow Currently Leontief is working with the economists. In fact, two works by Leon- Italian government to redesign the coun- tief (The Future of the World Econ- try’s entire transportation system (sea, omy~ and “Environmental repercus- air, road, and rail) through IOA. Most sions and the economic structure: an in- recently, he returned from Sapporo, Ja- put-output approach’~) are core to the pan, where he attended the Eighth Inter- 1985 research front “Input-output national Conference on Input-Output models for regional and energy analyses” Techniques. The first such conference (#85-6680). The other two core publica- was held in The Netherlands in 1952. tions making up thu cluster are Input- After lunch we walked through the Output and ,s4 by square to Leontiefs office, where he Harry W. Richardson, State University showed me a new French-language pub- of New York, Albany, and “US energy lication, “very elegantly done, “G that policy and , reprints several of his important articles 1975-2000,”SS by Edward A. Hudson, and includes a series of interviews he senior economist, Data Resources, Inc., gave the editors; an article by Anne P. Cambridge, Massachusetts, and Dale Carter and Peter A. Petri, Brandeis Uni- W. Jorgenson, professor of economics, versity, Waltham, Massachusetts, as- Harvard University. This research front, sessing his contribution to economics; with 30 citing documents, is connected and an excellent bibliography of hk to , as is evident works. T in the multidimensional scaliig map

278 F@e 2: Multidirnensional-scafing map for C2-level research front #85-0294, “ economic s,” showing links between Cl-level research fronts. The number of core/citing items are given in parentheses folfowing the research-front titles on the map. The size of the box around the research front number indicates the relative size of the citing literature-

Input-output models for regional and energy analyses (4/30) Demand and supply

(2/21)

Materials substitution 1 and in electric power, mining, 1398 and manufacturing Labor supply life (5/54) 1863 Consumer cycles stems and demand deman II (3/18) . (10/126)

\ / \ \

G:JrE,G:Qr782 Demographic implications

Poverfy, income utilify and 1323 systems (2/23) distribution (3/21 ) purchases (2/42)

“Supply and demand economics” in nomic problems of developing coun- Figure 2. tries” (#83-022 1), contains 32 core publi- In 1984 The Future of the World cations, including The Future of the Economy~a and The Future of Nonfuel Worid Economy,3a and 224 citing 1983 Minemis in the US and Wor[d Econo- articles. It is plain that this UN study, mY3zmade Up the entire core of research Leontiefs second most-cited publica- front #84-8233, “Projections of the tion, has been consistently important in distribution of nonfuel mineral re- research articles published over the past sources in the world economy, ” which three years. was crest ed from nine citing 1984 arti- Finally, I should emphasize that our cles. And in 1983 Leontief’s address list of Leontiefs most-cited publications “Theoretical assumptions and nonob- in Table 1 is to be read with two impor- served facts”@ and Analysis and Control tant cautions in mind. First, the S.!KX of Dynamic Economic Systems,sb by file, which contains the lion’s share of Gregory C. Chow, professor of econom- citations to works by Leontief, does not ics, Princeton University, New Jersey, begin until 1966, relatively late in Leon- formed the core of research front tief’s career; we do not yet have a record #83-4380, “Interactive macroeconomic of most citations to hk works for the 40 models,” created from 15 articles pub- years before this date. And, second, lished in 1983. A second 1983 research many of his articles that have been re- front, “Analyses of the political and eco- printed in monographic form are not ex-

279 plicitly identified in our count, We did its, Volume 1 and Volume J, 43,44 af-e not tackle the daunting task of determin- listed at the end of the table. ing the specific article involved when a volume of collected works was cited. An asterisk in Table 1 marks those among ***** Leontief’s most-cited articles that have been reprinted in monographs; there are more citations to these articles than the My thanks to C.J. Fiscus, David A. table indicates. Citations to Input-Out- Pendlebury, and Amy Stone for their put Economics4~ and Essays in Econom - help in the prepamtion of this essay. I Olw!elsl

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