Transaction-Cost Economics Past, Present, and Future

Scand.J.of Economics112(2),263–288,2010

DOI:10.1111/j.1467-9442.2010.01609.x

Transaction-Cost Economics:

Past,Present,and Future?

Robert Gibbons?

Massachusetts Institute of Technology,Cambridge,MA02142,USA

rgibbons@https://www.sodocs.net/doc/5011579726.html,

Abstract

Oliver Williamson is the founder and chief developer of transaction-cost economics(TCE). In this brief essay,on the occasion of his Nobel Memorial Prize,I offer a partial discussion of Williamson’s contributions by first summarizing some of the accomplishments of TCE-past and then sketching some of the opportunities for TCE-future.Most of the topics in both sections(TCE-past and TCE-future)start with a quotation from Williamson’s early work that I think still speaks volumes today.That is,while fellow travelers and successors have acted on one set of Williamson’s insights,helping to produce the accomplishments of TCE-past, another collection of Williamson’s insights has gone relatively unremarked,creating some of the opportunities for TCE-future.

Keywords:Oliver Williamson;Nobel;transaction costs;boundary of the firm

JEL classification:D23;L22;L24

I.Introduction

In2009,Oliver Williamson shared the Nobel Memorial Prize in Economics Sciences“for his analysis of economic governance,especially the bound-aries of the firm”.More generally,Williamson is the founder and chief developer of transaction-cost economics(TCE),with five books,seven edited volumes,and more than170papers on TCE and related topics.In this brief essay,therefore,I cannot offer more than a partial discussion of Williamson’s contributions(emphasizing that“partial”can mean both in-complete and biased).In particular,the first part of the essay summarizes some of the substantial accomplishments of TCE-past,and the second part sketches some of the intriguing opportunities for TCE-future.To conclude, I then briefly describe TCE-present as at a crossroads:celebrating its past and charting its future.

?I am very grateful to Richard Holden,Jon Levin,Hongyi Li,Scott Masten,Mike Powell, John Roberts,Scott Stern,Steve Tadelis,Tommy Wang,and Birger Wernerfelt for helpful comments,as well as to the Program on Innovation in Markets and Organizations at MIT’s Sloan School for financial support.

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Both of the essay’s parts,on TCE-past and TCE-future,are broken into a handful of topics.For example,one of the topics in the accomplishments of TCE-past concerns the boundary of the firm,and one of the topics in the opportunities for TCE-future concerns internal organization.But almost every topic in both parts,whether accomplishment or opportunity, starts the same way:with a quotation from Williamson’s early work that I think still speaks volumes today.The difference I see between TCE-past and TCE-future,then,is not that Williamson launched the former but ignored the latter;to the contrary,Williamson can be seen as trying to launch both.Instead,the difference I see is that fellow travelers and successors have acted on one handful of Williamson’s insights,producing the accomplishments of TCE-past,whereas another handful of Williamson’s insights has gone relatively unremarked,creating some of the opportunities for TCE-future.

Before diving in,I must issue an overarching caveat and apology: space constraints all but preclude discussion of contributions besides Williamson’s.Thus,this essay is more a celebration of an individual than a literature review.In particular,in Section II on TCE-past,I hope to clar-ify why the dedication of Williamson(1985)counts Coase and Simon as “teachers”,but I barely mention Williamson’s fellow travelers and succes-sors in TCE.Similarly,in Section III on TCE-future,I give only hints about recent developments in organizational economics that complement rather than directly build on TCE.For each section,a full discussion will require another outlet.

II.Some Accomplishments of TCE-Past

Both2009laureates,Williamson and Elinor Ostrom,are cited for their analyses of“economic governance”,but what does this mean?Dixit(2009, pp.5–6)defines the term as“the structure and functioning of the legal and social institutions that support economic activity and economic transactions by protecting property rights,enforcing contracts,and taking collective ac-tion to provide physical and organizational infrastructure...Good economic governance thus underpins the whole Smithian process whereby individuals specialize in different tasks and then transact with one another to achieve the full economic potential of the society.”

The2009Nobel Memorial Prize was a special moment for the study of economic governance,and there have been others(such as the earlier prizes to Buchanan,Coase,and North)because the institutions of economic gov-ernance explicitly affect or implicitly underlie huge parts of both economic activity and economics literature.We need institutions not only to sup-port simple exchanges in markets,but also to conduct both non-market transactions(in firms,communities,governments,and elsewhere)and C The editors of the Scandinavian Journal of Economics2010.

Transaction-cost economics:past,present,and future?265 complex transactions in markets(via contracts and other governance struc-tures that are not simple exchanges).When considering settings beyond simple exchange,including those analyzed by Ostrom and by Williamson, one sees why Buchanan(1975,p.229)argued that“economics comes closer to being a‘science of contract’than a‘science of choice’”.

To summarize the accomplishments of TCE-past,I focus on three topics: (1)methodology for studying particular governance structures and compar-ing them to others;(2)assumptions about the nature of certain important economic transactions and the devices available for governing them;and (3)applications,mostly to the boundary of the firm,broadly construed. Some of these accomplishments may now have become taken for granted, so that not everyone recognizes that there is an accomplishment there,not to mention who produced it.1

As primary sources for several of these accomplishments of TCE-past (and several of the opportunities for TCE-future discussed below),I draw heavily on Williamson’s1971,1973,and1979papers,as well as on Chap-ters4and5from his1975book.With the benefit of30years of hindsight (as well as the enormous body of Williamson’s subsequent writing noted above and the huge empirical literature on TCE discussed below),I have come to see these key writings from the1970s as expressing the core theo-retical ideas of TCE.2As Hahn(1961,p.204)said about Debreu’s Theory of V alue,I find the returns to re-reading these key Williamson writings to be“very high indeed and probably increasing”.

Methodology

Even before Williamson’s prize cited his analysis of“the boundaries of the firm”,his best-known contribution concerned the make-or-buy problem: which upstream inputs should a downstream business purchase and which should it manufacture?(Or,as Coase,1937,pp.393–394,put it,“Why does the entrepreneur not organize one less transaction or one more?”)

1This notion of being taken for granted parallels a story about my MIT colleague Barbara Liskov,an Institute Professor(the highest rank at MIT),who won the Turing Award in2008 for her work in the1970s.In response to the award,someone(much younger?)apparently wrote,“What did she get this award for?Everyone knows this,anyway”(https://www.sodocs.net/doc/5011579726.html,/ newsoffice/2009/liskov-event.html).

2T wo enormous omissions in what follows are that(1)I focus on what Williamson(1985, p.24)calls the“governance”branch of TCE rather than the“measurement”branch,thus entirely omitting important papers such as Alchian and Demsetz(1972),and(2)I focus almost entirely on Williamson’s arguments(both who made them and who used them),thus only barely mentioning Klein,Crawford,and Alchian(1978)under“Applications”in Section II and“Formal Models”in Section III.See Baker and Gil(2010)for more on Klein et al.’s role in launching active discussion of the central case study in this field,GM-Fisher Body.

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To analyze the make-or-buy problem,one might focus on the firm’s production function.After all,production functions are a standard topic in microeconomics courses,from introductory to advanced.As Demsetz (1983,p.377)notes,however,“It is a mistake to confuse the[neoclassical] firm...with its real-world namesake”.In particular,Williamson(1971, p.112)argues that production functions are not the way to analyze the make-or-buy problem.

“[T]he substitution of internal organization for market exchange is attractive less on account of technological economies associated with production but because of what may be referred to broadly as‘transactional failures’in the operation of markets for intermediate goods.”

The question,then,is how to analyze the sources and remedies of“trans-actional failures”.In this section,I discuss two aspects of the methodology that Williamson proposed and practiced:(a)microanalysis of transaction detail and(b)comparative institutional analysis.

(a)Microanalysis of transaction detail.Williamson’s approach to analyzing transactional failures is“microanalytic”(1976,p.74),meaning that it

“examine[s]the contracting process in[great]detail...to discern the types of difficulties which market mediated exchange encounters and,relatedly, to establish in what respects and why https://www.sodocs.net/doc/5011579726.html,anization offers an advantage.”

In this microanalytic focus on how governance structures reshape parties’incentives and opportunities,Williamson reflects ideas from his doctoral training at Carnegie-Mellon,such as March(1962,p.662)on“the business firm as a political coalition”and Cyert and March(1963[1992],p.202)on “the organization as a decision process”(which we revisit in Section III). This microanalytic approach contrasts in two respects with the production-function approach.First,a production function is a reduced form,abstracting from transaction detail.But,as the press release for Coase’s Nobel Prize stated,endorsing the spirit of microanalysis,“the power and precision of analysis may be enhanced if it is carried out in terms of rights to use goods and factors of production instead of the goods and factors themselves.”3Second,the standard optimization problems involving production functions are single-person problems,whereas studying trans-action detail typically reveals contending interests among the parties to a transaction;the microanalytic approach explores the parties’political and 3https://www.sodocs.net/doc/5011579726.html,/nobel_prizes/economics/laureates/1991/press.html.

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Transaction-cost economics:past,present,and future?267 strategic actions as a game rather than a single-person problem.As a result of these two differences,TCE can have a lot to say about production(see “Identification”in Section III for a start)but little reference to production functions.

Before leaving production functions,however,I find it interesting to note that,whereas Kreps(1990)treated organizational issues not only in Chapter7on“The Neoclassical Firm”but also in Chapter19on“Theories of the Firm”and Chapter20on“Transaction Cost Economics and the Firm”,Mas-Colell,Whinston,and Green(1995)included only a chapter on “Production”and placed it in their Part I—on individual decision-making. Given the literature in1995,I can understand the choices that Mas-Colell et al.made,but I hope it will someday be taken for granted that(a)the external boundaries and internal structures and processes of organizations should receive at least as much attention as production functions in leading micro texts and(b)these aspects of organizations should be analyzed from a microanalytic perspective(i.e.as reshaping the incentives and opportunities of the parties to the transaction in question).In short,I await textbooks that embody Cyert and March’s(1963[1992],p.30)view of organizations:“People(i.e.,individuals)have goals;collectivities of people do not”. (b)Comparative institutional analysis.As a methodological point, Williamson(1973,p.316)has long argued and practiced that “the problems of efficient economic organization need to be examined in a comparative-institutional way.”

For example,Coase(1937)and Williamson(1971)analyzed the make-or-buy problem as the efficient choice from a discrete set of alternative governance mechanisms(namely,integration and non-integration).Further-more,such comparative institutional analyses can be conducted not just of the boundary of the firm but also of its internal organization and other topics,as in the following three early examples.First,Simon(1951)and Williamson,Wachter,and Harris(1975)compared an“employment”rela-tionship(where the boss can choose the worker’s task)to various contrac-tual relationships(e.g.where the task is agreed in advance).Second,Coase (1960)and Williamson(1976)compared regulation to relevant alterna-tives(integration for Coase and franchise bidding for Williamson).Finally, Chandler(1962)and Williamson(1981)compared functional organizations (where each function reports directly to headquarters)to multi-divisional organizations(where each division contains each function and each divi-sion reports to headquarters).In each of these early studies,Williamson’s microanalytic approach considerably deepened the institutional comparisons initiated by his predecessors.

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Simon(1978,p.6)provided an early articulation of the motivation and methods of the comparative-institutional approach,noting that“[a]s economics expands beyond its core of price theory...,we observe in it...[a]shift from a highly quantitative analysis,in which equilibration at the margin plays a central role,to a more qualitative analysis in which discrete structural alternatives are compared”.Today,large literatures(not just TCE)have conducted comparative institutional analyses of a wide range of topics.For example,there are analyses of the optimal extent of horizontal integration(not just vertical),the optimal control structures inside organizations(not just functional and divisional forms),the optimal contracts and other governance structures between firms(such as joint ventures),and the optimal governance structures for the political economy (such as different constitutional and legislative structures).4But the point here is to identify early sources of this comparative-institutional approach, not to catalogue its many subsequent applications.

Assumptions(about Difficult Transactions)

In order to conduct microanalysis of alternative governance institutions, Williamson needed to reconceptualize the environment in which much important economic activity occurs.In this subsection,I focus on three environmental conditions that collectively can create“transactional fail-ures”(whether“in the operation of markets for intermediate goods”or elsewhere):(a)unprogrammed adaptation because ex ante contracts are in-complete,(b)lock-in arising from the“fundamental transformation”(1985, p.61),and(c)haggling(i.e.inefficient bargaining)because ex post con-tracts are incomplete.5

The“Applications”subsection below begins by focusing on vertical inte-gration in markets for intermediate goods,explaining that this combination of unprogrammed adaptation,lock-in,and haggling creates Williamson’s earliest rationale for integration.The remainder of that subsection then discusses other settings,beyond intermediate goods,where these three en-vironmental conditions again have important effects.

4See,for example,M′e nard’s(2004)International Library of the New Institutional Economics. 5Williamson(1973,1975,1985)emphasizes not only environmental conditions but also behavioral ones,especially bounded rationality and opportunism.I proceed slightly differently but to the same basic effect.Replacing bounded rationality,I assume that contracts can be incomplete even if the parties are rational.And endorsing opportunism,I assume that individuals are opportunistic in all economic models,even if in some settings,such as general-equilibrium models,such actors have so few opportunities that they“do not buy more than they can pay for,...do not embezzle funds,...[and]do not rob banks”(Diamond, 1971,p.31).In short,opportunistic actors in constrained environments behave well,but our interest is in other environments.

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Transaction-cost economics:past,present,and future?269 (a)Unprogrammed adaptation because ex ante contracts are incomplete. In the1960s,many general-equilibrium models assumed the existence of a complete set of state-contingent claims,as introduced by Arrow(1953) and Debreu(1959).In contrast,Williamson(1971,p.113)was consider-ing“unprogrammed adaptations”resulting from ex ante contracts that are incomplete.

“[O]nly when the need to make unprogrammed adaptations is introduced does the market versus internal organization issue become engaging.”Simon’s(1951)model has a similar spirit:in an“employment relationship”, the boss chooses the worker’s task after the state of the world has been realized,and Simon compared this governance structure for adaptation to a“sales”contract where the task is agreed before the state is realized (in which case there is no adaptation).The key point is that Simon did not allow the parties to write a contingent contract(prescribing the task as a function of the state)before the state is realized;that is,he ruled out what might be called programmed adaptation.In endorsing Simon’s incomplete-contract approach to adaptation(for studying the make-or-buy problem),Williamson can again be seen as reflecting his Carnegie roots, but it is worth noting what a departure this endorsement was from Arrow and Debreu’s complete-contract approach that was so prominent throughout the1960s.

The possibility of unprogrammed adaptation is important because dif-ferent governance structures can have different influences on the parties’response to the need for such adaptation.As Williamson(2000,p.605) later summarized three decades of work,TCE

“holds that maladaptation in the contract execution interval is the principal source of inefficiency.”

For example,one way that such maladaptation can arise is from privately optimal but collectively inefficient haggling.Whatever the sources and sizes of such maladaptations,the core TCE idea is that the efficient governance structure minimizes the resulting inefficiency.

(b)Lock-in arising from the“fundamental transformation”.If there are many equivalent upstream or downstream parties,then competition seems likely to produce an efficient outcome,even if ex ante contracts are incom-plete.Thus,a second ingredient in Williamson’s rationale for integration is lock-in via“bilateral monopoly”(1971,p.115)or“small numbers”(1973, p.318).

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Williamson’s contribution on this point is not to focus on settings that have small numbers from the beginning,but rather to explain why large numbers in the beginning often become small numbers over time,through specific investments,learning by doing,and so on.

“Although a large-numbers exchange condition obtains at the outset,it is transformed during contract execution into a small-numbers exchange...”

[1975,p.29]

Thus,for whatever reason,it often becomes more efficient for the parties to continue to deal with each other rather than change partners. Although specific investments have played a large role in the TCE lit-erature as a leading source of such lock-in,it is important to consider the possibility of lock-in even in the absence of specific investments.In this spirit,Masten,Meehan,and Snyder(1991,p.9)describe“temporal speci-ficity”as follows:“Where timely performance is critical,delay becomes a potentially effective strategy for extracting price concessions...Even though the skills and assets necessary to perform the task may be fairly common,the difficulty of identifying and arranging to have an alterna-tive supplier in place on short notice introduces the prospect of strategic holdups”.This issue of alternative sources of lock-in,beyond specific in-vestments,reappears below.

(c)Haggling arising from incomplete ex post contracts.In1971, Williamson had access to the Nash Bargaining Solution,which assumes efficient bargaining rather than inefficient haggling,but not to Tullock’s (1980)model of collectively inefficient rent-seeking behaviors or to mod-els of inefficient bargaining under asymmetric information such as Myerson and Satterthwaite(1983).On the other hand,as Williamson(1975,p.73) notes—citing Schelling(1960)and(1971)here and elsewhere in the book—“To observe that the pursuit of perceived individual interests can sometimes lead to defective collective outcomes is scarcely novel.”

Whatever his thoughts about the sources of inefficient haggling, Williamson(1971,p.115)clearly envisioned inefficient bargaining,assert-ing that

“[a]lthough this haggling is jointly(and socially)unproductive,it constitutes

a source of private pecuniary gain.”

As we will discuss in Section III,the literature is still debating how to formalize the idea of haggling in a way that produces a formal theory of vertical integration.Nonetheless,as we will see in the next subsection, C The editors of the Scandinavian Journal of Economics2010.

Transaction-cost economics:past,present,and future?271 even without a formalization of inefficient haggling,Williamson’s rationale for vertical integration inspired a great deal of empirical work. Applications

For environments that satisfy the three assumptions in the previous sub-section,Williamson could perform microanalytic comparisons of alternative governance institutions,beginning with the make-or-buy problem.This sub-section summarizes some of the ensuing applications,in four parts,largely concerning the boundary of the firm:(a)TCE’s theory of vertical integra-tion;(b)TCE evidence on vertical integration;(c)TCE theory and evidence on contracts between firms;and(d)further applications.

(a)TCE’s theory of vertical integration.As suggested above,the combina-tion of unprogrammed adaptation,lock-in,and haggling create Williamson’s earliest rationale for integration.To avoid inefficient haggling under non-integration,it may be more efficient to concentrate control,producing decision-making by fiat.As Williamson(1971,p.114)argued,

“fiat is frequently a more efficient way to settle minor conflicts...than is haggling or litigation.”

A more detailed argument appears in Chapters4and5of his1975book. Specifically,Chapter4argues that the need for unprogrammed adaptation implies that many labor transactions are more efficiently conducted in a firm(under something like Simon’s“employment relationship”)instead of in a market(under something like Simon’s“sales contract”).6Having made labor transactions the centerpiece of Chapter4,Williamson then makes an explicitly parallel case for intermediate products in Chapter5:“The argument here really parallels that of Chapter4in most essential respects”(1975,p.99).

In short,Williamson’s earliest rationale for vertical integration concerned choosing a governance structure to minimize the inefficiency of unpro-grammed adaptations.While Simon shared this focus on unprogrammed adaptation,there are three important advances in Williamson’s argument. 6Williamson(1975,pp.71–72)critiques both Simon’s(1951)sales contract and his employ-ment relationship,the former for ignoring contingent claims and sequential spot contracting and the latter because it is ill suited for large-scale adaptations(e.g.where the boss’s and worker’s interests diverge substantially).In my view,however,these critiques under-appreciate further contributions in Simon’s paper:importantly,Simon also considered an alternative governance structure(namely,letting the worker decide,p.304)and the role of repeated interactions in moving a decision-maker’s decisions away from short-run self-interest and towards Pareto-efficiency(p.302).

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First,whereas Simon analyzed a setting with only two parties,Williamson endogenized the small-numbers context via the fundamental transformation. Second,Simon analyzed a setting with only one decision(the worker’s task),so Williamson’s interests in non-integration and its associated hag-gling could not arise.And third,in a bold analogy,Williamson argued that issues akin to those in employment also arise for intermediate goods.

For both theoretical and empirical purposes below,let me reiterate that, although this rationale for vertical integration does require lock-in from small numbers,it does not require specific investments to be the source of that lock-in.(In particular,Simon says nothing whatsoever about in-vestments.)To put this differently,one could say that Williamson’s earliest rationale for integration requires specificity but not specific investments.

I make this point not because the1975argument was incomplete,but rather the reverse.Given the strong emphasis on specific investments in later work,a completely coherent argument in the1975book(based on specificity without specific investments)largely got lost.7

Increased emphasis on specific investments occurred in Klein et al. (1978,pp.297–298),who analyzed“post-contractual opportunistic behav-ior”(i.e.haggling)over“appropriable specialized quasi rents...[created by]a specific investment”,and in Williamson’s1979paper,where he fo-cused on“economic activity that involves transaction-specific investments in human and physical capital”(p.234).Having thus identified a lead-ing cause of lock-in,Williamson(1979,pp.252–253)then returned to the rationale for vertical integration sketched above.

“The choice of organizing mode then turns on which mode has superior adaptive properties...The advantage of vertical integration is that adap-tations can be made...without the need to consult,complete,or revise interfirm agreements.”

In sum,by1979,Williamson had made the argument that specific in-vestments cause small numbers and,under non-integration,unprogrammed adaptations invite inefficient haggling.A large empirical body of TCE literature on vertical integration followed,to which we turn next.

(b)TCE evidence on vertical integration.So far,I have spent this entire essay discussing theory.On the one hand,this seems appropriate,because Williamson’s main direct contributions have been theoretical.On the other, 7As one way to assess the increased emphasis on specific investments,compare the indexes of the1975and1985books.In1975,the words“asset”and“investment”and“specific”do not appear,but“small-numbers exchange condition”appears10times;whereas in1985,“small numbers”does not appear,but phrases related to“asset specificity”or“transaction-specific”assets and the like now appear77times.

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Transaction-cost economics:past,present,and future?273 this seems odd because the huge body of TCE literature is overwhelmingly empirical.To bridge this disjuncture,I now consider Williamson’s largest indirect contribution:operationalizing TCE so that empiricists sought to test it.In particular,I focus here on the empirical TCE literature on vertical integration and below on the theoretical and empirical TCE literature on contracting.

For empirical work on both of these core TCE issues—vertical integra-tion and contracting—the key step was the1979paper,which began by asserting that

“[f]urther progress in the study of transaction costs awaits the identification of the critical dimensions with respect to which transaction costs differ”

[p.234]

and then nominated uncertainty,investment idiosyncracy,and frequency as the critical dimensions of transactions.Relative to the three ingredients in the rationale for integration described above,Williamson argues that uncer-tainty creates unprogrammed adaptations and that investment idiosyncracy creates lock-in.Haggling,the third ingredient in the rationale for integra-tion,is assumed to be omnipresent,or at least very widespread.8Finally, the third transaction dimension nominated in the1979paper,frequency with which the transaction recurs,is beyond the scope of this subsection’s focus on vertical integration and contracting.9

Among the first empirical papers testing TCE’s predictions concern-ing vertical integration were Monteverde and Teece(1982)and Masten (1984).Monteverde and Teece studied133automobile components used by Ford and General Motors and found that components requiring greater engineering development effort are more likely to be produced in-house. Engineering development effort can be interpreted as specific human capi-tal,creating lock-in,and the other two ingredients in Williamson’s rationale for integration—unprogrammed adaptations and haggling—are assumed to be present.For his part,Masten(1984)analyzed a large aerospace project, constructing measures of specificity and complexity for each input and

8More specifically,Williamson assumes that opportunism is widespread(p.234)and creates haggling if parties are given the chance to haggle(such as under non-integration).Given later models of inefficient bargaining such as Tullock(1980)or Myerson and Satterthwaite(1983), I would restate this assumption as opportunism and ex post contracts that are incomplete create haggling if the parties are given the chance.

9Williamson(1979)argues that frequency provides a boundary condition separating private ordering(where only the parties themselves are involved in governance),which is efficient for high-frequency transactions,from trilateral governance(where a third party such as an arbitrator is involved in governance),which is efficient for low-frequency transactions. This section’s focus on private ordering can thus be interpreted as assuming high-frequency transactions.

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finding that the combination of these two measures is especially important in explaining which inputs are produced in-house.Thus,Masten’s analysis not only attempts to measure two of the three ingredients in Williamson’s rationale for integration but also recognizes that all three ingredients must be present for the rationale to apply(and,like Monteverde–Teece and suc-cessors,assumes that haggling is present).

Many other(perhaps100!)empirical TCE papers on vertical integration followed.Because this space-constrained essay focuses on Williamson’s contributions,I cannot survey these ensuing papers and so will resort in-stead to surveying the subsequent surveys.Shelanski and Klein(1995)and Macher and Richman(2008)focus on the breadth and quantity of empir-ical work broadly in keeping with TCE insights,not limited to vertical https://www.sodocs.net/doc/5011579726.html,fontaine and Slade(2007)and Bresnahan and Levin(2010) focus on vertical integration,consider theories beyond TCE,and pay in-creased attention to measurement and econometric issues.David and Han (2004)and Carter and Hodgson(2006)offer more critical assessments of the power and interpretation of TCE tests concerning vertical integration and contracting.

(c)TCE theory and evidence on contracts.Although Williamson and TCE may be best known among economists for analyzing the make-or-buy prob-lem,there is a sense in which the main issue in TCE is actually contracting, with integration being a special case.More specifically,Williamson’s early work(e.g.the1971and1973papers and the1975book)focused on mar-kets versus hierarchies,where the vision of non-integration emphasized the hazards more than the advantages of contracting between firms.But the title of the1979paper is“Transaction-cost Economics:The Governance of Contractual Relations”(emphasis added),and the preface of the1985 book argues that

“any issue that either arises as or can be recast as a problem of contracting is usefully examined in transaction cost terms.”[p.xii]

Moving from titles and prefaces to analysis,the two main governance structures studied in the1979paper(pp.250–253)are bilateral governance (i.e.contracting under non-integration)and unified governance(i.e.con-tracting under integration);and the1983paper focused solely on“the use of bilateral governance structures(private ordering)to implement nonstan-dard contracts where the adaptation and continuity needs of the parties are especially great”(p.537).In short,by the early1980s,contracts had become at least as central to TCE as integration.

As Joskow(1985)emphasizes,the first question to be asked about con-tracts between firms is not which contract is chosen but rather why the C The editors of the Scandinavian Journal of Economics2010.

Transaction-cost economics:past,present,and future?275 parties are contracting at all.Furthermore,in choosing whether to con-tract,the parties are comparing this option to two alternatives:arm’s-length transacting on one hand and integration on the other.It would be good to see more explicit treatment of both these alternatives in future theoretical and empirical work.See Masten and Saussier(2000)and Lafontaine and Slade(2010)for surveys on the empirical side.

Having decided to contract,the parties then need to decide on terms, such as contract duration,pricing and price adjustment,vertical restraints, and so on.TCE empirical work on contracting often studies how contract terms depend on key drivers from the TCE theory,such as unprogrammed adaptation and haggling(or,as they are sometimes proxied,uncertainty and appropriation hazards).For example,see Joskow(1987)on duration and Masten and Crocker(1985)on the role of take-or-pay clauses in adaptation. As with the TCE empirical work on vertical integration,the TCE empirical literature on contracting is sufficiently large that I again resort to sur-veying the surveys:in addition to Masten–Saussier and Lafontaine–Slade, which are specifically about contracts,see also the contracts sections of the aforementioned Shelanski–Klein and Macher–Richman empirical TCE surveys.

While TCE research on contracting has been overwhelmingly empirical, recent formal modeling by Bajari and Tadelis(2001)on the effect of com-plexity on contract design is very much in the spirit of TCE’s informal arguments about contracts.As we discuss under“Formal Models”in Sec-tion III,building on the Bajari–Tadelis approach is a promising method for trying to formalize TCE’s arguments about integration.

Finally,there is one last body of empirical literature(again with many papers—perhaps140when combined with the contracts papers above), not exactly on integration and not exactly on contracting,but relevant nonetheless.This is the literature on“hybrid”governance structures,the simplest of which is perhaps a joint venture(e.g.Pisano,1989),but others of which involve many parties,many assets,and many contracts (e.g.M′e nard,1996).See M′e nard(2010)for a survey dedicated to hy-brids,as well as the hybrids sections of Shelanski–Klein and Macher–Richman.

(d)Further applications.Williamson has long argued that the study of organization should combine law,economics,and organization theory.In-deed,he argues(1985,pp.2–7)that one can discern these three sources as far back as the1930s in Llewellyn(1931),Coase(1937),and Barnard (1938),respectively.Furthermore,in addition to the comparatively abstract arguments about vertical integration and contracting in the1971,1973,and 1979papers,Williamson also performed more applied analyses on topics relating law and economics,such as antitrust(1968)and regulation(1976),

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and edited a book of contributions(including one of his own)on Chester Barnard and organization theory(1990).

In keeping with this breadth in Williamson’s interests and background, among his most cited publications are articles in sociology,law,and organ-ization journals(1981,1984,and1991,respectively).More importantly,and to go beyond simple citations,perhaps the most striking fact documented in the Macher–Richman survey is that TCE has inspired research on a wide variety of subjects in a wide variety of fields.These include areas within economics(such as industrial organization,law and economics,and regulation),management disciplines(such as marketing,strategy,and inter-national business),and other social sciences(such as political science and sociology).This broad set of applications(and others not mentioned here) extends well beyond the boundary of the firm,even if integration,con-tracts,and hybrids may be the original core of TCE theory and evidence. We return to the interplay between Williamson and sociologists below. III.Some Opportunities for TCE-Future

Having spent most of this essay on the accomplishments of TCE-past,I now briefly discuss some opportunities for TCE-future.Just as space constraints limited the discussion of Williamson’s fellow travelers and successors in TCE,they also allow only a mere mention of recent developments in organizational economics that complement rather than directly build on TCE.

I focus on four opportunities for TCE-future:(1)costs of integration,

(2)identification,(3)internal organization,and(4)formal models.As with many of the accomplishments of TCE-past,several of these possible topics for TCE-future are consistent with observations Williamson made in the 1970s.

Costs of Integration

Williamson articulated the main point of this subsection long ago:“A complete treatment of vertical integration requires that the limits as well as the powers of internal organization be assessed.”[1971,p.113] Unfortunately,a more recent assessment suggests only partial progress on this agenda.

“The main benefits of vertical integration...are discerned by examining the problems that attend autonomous contracting when the parties to a trade are operating in a bilateral exchange relation.The main costs of vertical integration are more difficult to discover,however.”[1985,p.153]

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Transaction-cost economics:past,present,and future?277 Williamson(1985)discussed several possible costs of integration,includ-ing“accounting contrivances”(p.138),transfer prices that are determined “unilaterally”(p.139),and“the strategic propensity to use the resources of the organization to pursue subgoals”(p.149).Many of these“costs of bureaucracy”(p.148)might be summarized as abuse of fiat(i.e.oppor-tunistic use of concentrated control).The corporate governance literature—for example,Shleifer and Vishny(1997),Core,Holthausen,and Larcker (1999),and Gompers,Ishii,and Metrick(2003)—takes abuse of fiat very seriously,so it is easy to imagine opportunistic use of concentrated con-trol under integration.One concern,however,is that the factors that make haggling very inefficient under non-integration seem likely to be corre-lated with those that make abuse of fiat very inefficient under integration. Indeed,Williamson suggested the following early intuition.

“[S]ubstantially the same factors that are ultimately responsible for market failures also explain failures of internal organization.”[1973,p.316] Unfortunately,if one is to preserve the original interpretation of the large body of empirical TCE literature on vertical integration,it is difficult to argue that abuse of fiat is a chief cost of integration.That is,the standard and simplest interpretation of this empirical literature is that the costs of integration are in the error term and orthogonal to the regressors that proxy for costs of non-integration,but this orthogonality assumption is violated if the factors that make haggling very inefficient under non-integration are correlated with those that make abuse of fiat very inefficient under integration.As Masten et al.(1991,p.1)put it,“recognition that variations in internal organization costs may also play a role in the decision to integrate exposes an inherent weakness in...[the existing]tests”.

In short,TCE theory does not provide as clear an explanation for varia-tions in the costs of integration as it does for the costs of non-integration. Without a theory of variations in the costs of integration,it is difficult to know which factors responsible for market failures are correlated with (or even identical to)factors responsible for organizational failure.One could simply ignore these issues and assume that the costs of integra-tion are orthogonal to the proxies for the costs of non-integration.Fur-thermore,one could choose to study the effect on vertical integration of the costs of non-integration rather than the costs of integration.Indeed, from Monteverde–Teece and Masten onward,essentially all TCE empirical papers on vertical integration have asked whether proxies for unpro-grammed adaptation and lock-in make integration more likely,with very few asking instead whether factors that increase the costs of integration make non-integration more likely.For example,an attempt to separate pa-pers cited in Shelanski and Klein(1995),Lafontaine and Slade(2007),and

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278R.Gibbons

Macher and Richman(2008)on this basis suggests that fewer than5%of the papers are in the latter category.

As I suggest in the“Formal Models”subsection below,we are moving towards theories in which“substantially the same factors that are ultimately responsible for market failures also explain failures of internal organiza-tion”.As such theories mature,it will be important both to derive their implications for the interpretation of estimated coefficients in the tradi-tional TCE regressions on vertical integration and to discover new estima-tion strategies that help us understand not only the benefits but also the costs of integration.See Masten et al.(1991)for probably the most serious attempt to address these issues thus far.

Identification

Besides the econometric issues associated with the possible failure of or-thogonality between the costs of non-integration and the costs of inte-gration,there are various other econometric issues that deserve attention.

I begin by collecting four long-standing but still important observations. First,it would be helpful to measure inefficient haggling directly,rather than use asset specificity as a proxy for the possibility of haggling.As Winter(1988,p.172)notes,“progress has been achieved not by the devel-opment of techniques for measuring transaction costs directly but by the development of operationalizing hypotheses to suggest where transactional difficulties are likely to be severe”.Second(and related),in addition to the incidence of vertical integration,it would be helpful to know more about its effects.As Joskow(1991,pp.81–82)put it,“we need more than an ordinal ranking of the efficiency of different organizational arrangements. We would like to know how much we lose by going from the best to the next best”.Third,Williamson’s rationale for vertical integration requires all three ingredients(unprogrammed adaptation,lock-in,and haggling),so the appropriate regression estimates the effect of the interaction of these ingredients,not their individual effects(unless,of course,one or more of these ingredients can be presumed to be present throughout the sample). As Lafontaine and Slade(2007,p.660)note,“[g]iven the importance of the interaction between specificity and contractual incompleteness in the theory,it is surprising that it is rarely tested directly”.Finally,as Kogut and Zander(1992,p.394)observed,the evidence in Monteverde–Teece—one of the most famous empirical papers supporting TCE—is at least as strong for a“capabilities”view of the firm.10

10More specifically,while Monteverde and Teece is widely cited for its finding that auto-mobile components requiring greater engineering development effort are more likely to be produced in-house,the t-statistic on the firm dummy variable is higher than those on any C The editors of the Scandinavian Journal of Economics2010.

Transaction-cost economics:past,present,and future?279 In addition to these long-standing observations,there is also a general trend in applied microeconometrics that is important to acknowledge and adopt:in a wide range of fields including labor,public finance,develop-ment,and beyond,there is an increased emphasis on quasi-experiments and causal inference,such as Angrist(1990)and Card(1990)in labor.While it is natural that empirical work from the1980s(in any field)did not adopt this quasi-experiment approach,and while there are some papers on vertical integration and contracting that exploit plausibly exogenous variation in the costs of alternative governance structures—such as Forbes and Lederman (2009)on the integration of regional airlines with majors—it remains the case that empirical work in TCE(and in organizational economics more generally)could stand to pay more attention to identification strategies. Internal Organization

Interestingly,even though Williamson is best known and celebrated for his work concerning the boundary of the firm(on both integration and con-tracts),from the beginning he showed an equal interest in internal organ-ization.For example,the1973paper is equally divided between analyses of(a)the integration decision and(b)alternative structures for internal organization.Likewise,each of the1975and1985books has about the same number of chapters devoted to internal organization as to the bound-ary of the firm.Among the internal-organization topics are the employ-ment relationship,the organization of work,peer groups,hierarchy,multi-divisional firms,and corporate governance.Finally,while some readers recall the full title of the1975book as Markets and Hierarchies:Analy-sis and Antitrust Implications,only a few seem to know that the subtitle (visible only on the title page)is A Study in the Economics of Internal Organization.

For some reason,Williamson’s ideas about internal organization did not inspire empirical follow-up the way his ideas about integration and contract-ing did.Certainly in the early going and even to this day,TCE empirical work tilts very significantly towards studies of the boundary of the firm, with little attention to internal organization.(This point is related but not identical to the earlier observation that TCE empirical studies of vertical in-tegration predominantly explore the costs of non-integration rather than the costs of integration.)For example,an attempt to separate the papers cited other independent variables,including engineering effort.See Winter(1988)and Langlois and Foss(1999)on the capabilities view,including its emphasis on production rather than exchange,heterogeneity rather than inefficiency,and path-dependence rather than stationarity. Interestingly,these issues are(finally)surfacing in organizational economics;see Gibbons (2010,Sec.4)for an overview,Gibbons and Henderson(2010)for a survey,and Chassang (2010)for an initial model.

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280R.Gibbons

in Shelanski–Klein and Macher–Richman by their focus on the boundary of the firm versus internal organization suggests that only a small mi-nority of the papers are in the latter category(although there are papers on multinationals,and it is not clear how to categorize some papers on hybrids).11

Even though Williamson’s ideas about internal organization have not re-ceived much empirical attention,he did point in some interesting directions. For example,

“it is opportunism in conjunction with both a small numbers and an infor-mation impactedness condition that accounts for the transactional disabilities that internal organization experiences...Internal opportunism takes the form of subgoal pursuit—where by subgoal pursuit is meant an effort to manip-ulate the system to promote the individual and collective interests of the affected managers.Such efforts generally involve distorting communications in a strategic manner...The upshot of this is that distortion-free internal exchange is a fiction and is not to be regarded as the relevant organizational alternative in circumstances where market exchange predictably experiences nontrivial frictions.”[1975,pp.124–125]

These ideas clearly relate to the discussion in the“Costs of Integration”subsection.Indeed,the“subgoal pursuit”Williamson envisions within firms may be related to the“haggling”he envisions between firms,so it may well be possible to develop a unified theory in which“substantially the same factors”are responsible for the costs of both integration and non-integration.In this subsection,however,my focus is not on the costs of integration or the make-or-buy problem but rather on developing a theory of internal organization(under the assumption,for the moment, that the parameters are such that integration performs better than non-integration).

Given this focus,I have three reactions to Williamson’s ideas on inter-nal organization.First,these ideas are quite different from the prominent approach to the economics of internal organization in the early1970s: Marschak and Radner’s(1972)team theory,which ignored incentive con-flicts so as to focus on information gathering,communication,and decision-making.Second,as suggested in the“Methodology”subsection,this micro-analytic approach to internal organization echoes the theory and evidence of 11One might wonder whether empirical work on internal organization is simply harder to produce than empirical work on the boundary of the firm.This could be true,but papers such as Baker(1992),Baker,Gibbs,and Holmstrom(1994),Baron,Burton,and Hannan(1999), Bertrand,Mehta,and Mullainathan(2002),Bloom and Van Reenen(2007),Henderson and Cockburn(1996),Ichino and Maggi(2000),Ichniowski,Shaw,and Prennushi(1997),Lazear (2000),and Mas and Moretti(2009)demonstrate many different styles of such work;see Baker and Gil(2010)and Ichniowski and Shaw(2010)for more.

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Transaction-cost economics:past,present,and future?281 the Carnegie School’s political view of organizations(summarized above as“the business firm as a political coalition”and“the organization as a decision process”).More specifically,Cyert and March(1963[1992]) argued that“[w]here different parts of the organization have responsibil-ity for different pieces of information...,[we would expect]some at-tempts to manipulate information as a device for manipulating the decision”(p.79).Indeed,Cyert and March went further,anticipating game-theoretic arguments such as Crawford and Sobel(1982)by noting that“we cannot reasonably introduce the concept of communication bias without introdu-cing its obvious corollary—‘interpretive adjustment’”(p.85).Third,all of this(Williamson and Cyert–March)has a very current feel.For example, there is now active research in how parties choose firm boundaries and internal control structures in part to affect incentives to gather and commu-nicate information.See Milgrom and Roberts(1988)and Holmstrom and Tirole(1991)for early work;Alonso,Dessein,and Matouschek(2008), Rantakari(2008),Dessein,Garicano,and Gertner(2010),and Raith and Friebel(2010)for recent work;and Gibbons(2010,Sec.3)for more on this literature.

Formal Models

Williamson’s contributions to TCE are a counter-example to Krugman’s (1995,p.27)dictum(originally composed for economic geography but equally applicable across most of economics):“Like it or not,...the influence of ideas that have not been embalmed in models soon decays”. Recognizing that his ideas had not been“embalmed in models”,Williamson argued that TCE was moving through a

“natural progression...[from](1)informal analysis...[to](2)preformal and(3)semiformal stages,...[culminating]with(4)fully formal analysis.”

[1993,p.38]

Cautioning against

“[p]rematurely formal theory[that]purports to deal with real phenomena without doing the hard work of making serious contact with the issues”

[1993,p.43],

Williamson nonetheless clarified that

“[s]ome might infer the progression begins with big ideas and ends with marginal refinements.That would be wrong.Important conceptual advances [are needed]at each stage of the process.”[1993,p.39]

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282R.Gibbons

This subsection attempts to illustrate both the kinds of“conceptual ad-vances”that are necessary for“fully formal analysis”and why they can be important.

We economists are so used to seeing our theory in formal models that we do not often ask why this is or when it should be.There are three familiar benefits of formal modeling.First,formal models can check the internal consistency of informal arguments,including providing boundary conditions under which the informal argument holds.Second,formal mod-els can help specify and interpret empirical tests of informal arguments. And third,formal models sometimes deliver results that few of us could have anticipated without the model(as discussed below).

A fourth benefit is perhaps less familiar but equally germane:formal models can help diagnose what is amiss in a theory when new evidence proves the original to be flawed,as in the following example.In his1975 book(pp.108–109),Williamson largely dismissed the“hybrid”governance structures mentioned at the end of“TCE Theory and Evidence on Con-tracts”above.Then,in his1985book(p.83),he seems to have seen new evidence and(sensibly)changed his mind:“Whereas I was earlier of the view that transactions of the middle kind were very difficult to orga-nize and hence were unstable,...I am now persuaded that...[they]are much more common”.Finally,in his1991paper,hybrids are on par with markets and hierarchies as outcomes driven by asset specificity(Fig.3, p.292).To me,this progression shows Williamson having the right reac-tion to new evidence,but I am left not knowing how to amend the original theory.Where did the original argument go astray?Was there a logical error,or was a boundary condition violated?If so,does this imperfection in the original theory have implications for other applications?At least in my experience,there is a better chance of amending the argument if one can see the original formally exposited.

An interesting side point,in connection with the multi-disciplinary roots and applications of TCE discussed at the end of Section II,is that theory and evidence of the kind developed and synthesized by sociologists such as Granovetter(1985),Stinchcombe(1985[1990]),and Powell(1990)seem to have played a role in swaying Williamson’s opinion about hybrids.Freeland (1996)is another example of cross-disciplinary feedback,in his sociological comparison of TCE theory on multi-divisional firms to detailed evidence from the early decades of General Motors.

In short,for all four of the reasons given above,it would be very helpful to have a formal theory that captures Williamson’s TCE arguments.It may be that Tadelis(2010),building on Bajari and Tadelis(2001),has started on a path towards this goal.In particular,Tadelis’s model can be interpreted as covering the case of specificity without specific investments,as discussed above.And,digging more deeply into the possible micro-foundations of C The editors of the Scandinavian Journal of Economics2010.

pr值计算方法

2012谷歌pr值计算方法大揭秘（将启用新颖度算法） 一，2012年谷歌友情链接计算新方法 + 十大谷歌参数值（为了方便理解姑且定义为参数） A B N代表不同的站点 很少有SEO人员懂的这种终极算法，这种谷歌参数超级重要，就算没有友情链接，只要将参数作到极致，完全可以提高pr值.这就是量变而引起的质变，也就是说不设置一个友情链接，pr照样可以提高到5,这篇文章我会好好解答其中的奥妙，以及谷歌在2012年pr值计算方面的新改变。 二，对pr计算公式的解析 谷歌对于网站友情链接或者是页面pr的计算方式是： PR(A)=(1-d)+d(PR(t1)/C(t1)+PR(t2)/C(t2)..........PR(tn)/C(tn))+（参数） 大家不知道这个d0.85是啥意思，d为固定的常数，也就是0.85 而PR(A)则是你网站可以获得的pr值，PR(t1)是交换网站的pr值，C(t1)则表示该网站所含有的导出的友情链接数，以此类推。专业名词叫阻尼因数(damping factor)，实际上是计算PR分值所设置的系数，Google 的阻尼因数一般是0.85PR(A)表示的是从一个外部链接站点t1上，依据Pagerank(tm)系统给你的网站所增加的PR分值PR(t1)表示该外部链接网站本身的PR分值;C(t1)则表示该外部链接站点所拥有的外部链接数量，很多SEO们的行家们迷信这个基础算法，而忽视了后边的参数，如果简单的利用这个基本的公式计算，发现会有一个漏洞，就是老网站获得的PR值会高，新网站即使很受欢迎仍然不能获得PR！

实则不然！大家都会发现三个怪现象， 1，有的网站刚上线没几天pr会更新到4 ， 2，有的网站友情链接做的越来越多，而pr却不断的在下降 3，有的网站根本没有友情链接，pr却也很高 这就是中国式的常规猜想，而忽略了后边的后浪参数，所以搜索引擎会有很复杂的算法来解决。不要深究算法，因为你不是搜索引擎工程师，研究提高PR没有更大的意义，所谓万变不离其宗，网站要获得高的PR值，友情链接不管是质量和数量上都有优势的时候才能走向PR的巅峰。同样，光靠参数，pr也可以走向一个巅峰。 三，友情链接因参数而不同 交换友链要考虑三方面的因素： （1）pr越高越好（最好是让高PR值的网站首页链接上你的网站，这是大部分人在做的） （2）pr不太高，但是导出连接比较少（很多做友情链接都不能彻底明白这一点，但通过计算公式很多人就明白了，pr不太高，但导出链接少的，甚至比pr高的网站，但为啥pr高是首要因素呢？因为导出链接少的pr还凑合的网站比较稀少） （3）权威网站的主要页面，或者叫后浪参数比较高的页面（很多做友情链接的都忽视这一点，网站是否权威，网站权威性与网页权威性这两个概念是有所区此外。网站权威性是由一张张高质量的网页、网站声望、用户口碑等等身分形成。搜索引擎判定一张网页的主要性，可能会优先判定网站的权威性。基于网站的权威性，再判定某一网页

Premiere切换特效汇总

视频切换特效 1.( )使画面像纸一样被重复折叠从而显示另一画面。 2.( )使画面以屏幕的一边为中心从后方转出覆盖另一画面。 3.( )使画面以屏幕的一边为中心从前方转出覆盖另一画面。 4.( )使画面从屏幕的中心逐渐展开覆盖另一画面。 5.( )使画面从屏幕的中心旋转出现而覆盖另一画面。 6.( )使画面像窗帘一样被拉起出现另一画面。 7.( )使画面以立方体的两个面进行过渡转换。 8.( )使两个画面作为页面，通过翻转实现转换。 9.( )使画面从屏幕的中心旋转缩小消失，出现另一画面。 10.( )使画面以关门的方式覆盖另一画面。 11.( )使画面从中心以矩形不断放大覆盖另一画面。 12.( )使画面以十字形向外移动显示另一画面。 13.( )使画面以圆形逐渐放大覆盖另一画面。 14.( )使画面以一个或多个形状打开覆盖另一画面。 15.( )使画面以星形不断放大覆盖另一画面。 16.( )使画面以交叉点擦除显示另一画面。 17.( )使画面以菱形逐渐放大覆盖另一画面。 18.( )画面从屏幕中心逐渐向四角撕开并卷起显示另一画面。 19.( )画面以翻页的形式从一角卷起显示另一画面(背面为灰色)。 20.( )画面以卷纸的形式从一边卷起显示另一画面(卷轴)。 21.( )画面以透明翻页的形式从一角卷起显示另一画面。 22.( )画面在中心分成四块分别卷起显示另一画面。 23.( )淡入淡出效果。 24.( )画面以点的方式叠加后逐渐显示另一画面。 25.( )画面逐渐变白后，由白色逐渐显示另一画面。 26.( )两画面以加亮模式交叉叠加后逐渐显示另一画面。 27.( )画面以随机反色显示的形式消失，逐渐显示另一画面。 28.( )两画面以亮度叠加消融的方式切换。 29.( )画面逐渐变为黑色后，由黑色逐渐显示另一画面。 30.( )画面从不同方向挤压显示另一画面。 31.( )一个画面淡出，另一个画面放大流入。 32.( )一个画面在另一个画面中心横向伸展开来。 33.( )一个画面从一边以伸缩状展开覆盖另一个画面。 34.( )画面沿着“Z”字形交错扫过另一画面。 35.( )画面从中央以开关门的方式转到另一画面。 36.( )画面以棋盘状消失过渡到另一个画面。 37.( )画面从水平、垂直或者对角线的方向以条状覆盖另一画面。 - 1 -

PR特效的应用

1．Brightness & Contrast（亮度与对比度） 本视频滤镜效果将改变画面的亮度和对比度。类似于电视中的亮度和对比度的调节，但在这里调整则是对滑块的移动， 2．Channel Mixer（通道合成器） 使用本视频滤镜效果，能用几个颜色通道的合成值来修改一个颜色通道。使用该效果可创建使用其他颜色调整工具很难产生的颜色调整效果，通过从每个颜色通道中选择其中一部分就能合成为高质量的灰度级图像，创建高质量的棕褐色或其他色调的图像，已经交换或复制通道， 3．Color Balance（色彩平衡） 本视频滤镜效果利用滑块来调整RGB颜色的分配比例，使得某个颜色偏重以调整其明暗程度。本过滤属于随时间变化的特技， 4．Convolution Kernel（回旋核心） 本视频滤镜效果使用一道内定的数学表达式，通过矩阵文本给内定表达式输入数据，来计算每个像素的周围像素的涡旋值，进而得到丰富的视频效果。可以从提供的模式菜单中选择数据模式进行修改，也可以重新输入新的值（只要效果认为在Convolution Matrix（回旋矩阵）文本框中，中心的数字为该像素的亮度计算值（所输入的数字会乘以像素的亮度值），周围的数字是该像素周围的像素所需要的计算值，在此框内所输入的数值会乘以周围像素的亮度值。 在Misc（杂项）框架中的Scale文本框中输入的数将作为除数，像素点包括周围像素点的像素点与输入给“环境中心像素点的数据矩阵”对应点的乘积之和为被除数。Offset文本框是一个计算结果的偏移量（与所得的商相加）。 所有数值允许的输入范围很大，可从-99999～999999，但实际使用的没有这么大，要根据演示效果而定。 假如发现定义的一套数据很实用，并且以后还要使用，可单击Save按钮将其存储起来，并记住文件夹和文件名（或存储到软盘上）。下次通过单击Load按钮将其装载到当前的数据定义格式中，即可使用。 假如想使用内定的图像转换数据格式，应该单击图7-20中间上方的按钮，从弹出的菜单中选择相应的选项。内定的图像转换数据格式是十分有用的工具，它可让图像变得模糊或清楚。为能充分说明问题，图7-21列出了几种典型的效果供参考。这是从图7-20中选择的典型代表。这些视频效果在制作静态图片的特别节目时非常有用。它类似于Adobe Photoshop 中的过滤效果，只是在这里用于电影制作方面。假如不了解Premiere这个绝活，可能还会想到使用Photoshop进行处理。而假如将一幅照片通过Photoshop加工后再用于电影制作，势必会造成磁盘空间上的浪费和时间浪费。在此可看出Premiere的高效能力。5．Extract（提取） 当想利用一张彩色图片作为蒙板时，应该将它转换成灰度级图片。而利用此视频滤镜效果，可以对灰度级别进行选择，达到更加实用的效果。图7-22是提取视频片断的蒙板成分的对话框。 有2个滑块，带有图线的2个黑3角的滑块用来选定原始画面中的被转换成白色的灰度，Softness滑块用来调节画面的柔和程度。通过Invert复选框可以将已定的灰度图片进行反相。左下角的黑色梯形图（反相时为白色）随着Softness的滑动而变化，当变为三角形时，表明已达到原始画面的效果；当为梯形时，表明对原始画面的明暗分界进行了改动。6．Levels（色彩级别） 本视频滤镜效果将画面的亮度、对比度及色彩平衡（包括颜色反相）等参数的调整功能组合在一起，更方便地用来改善输出画面地画质和效果。图7-23是其调整对话框。

premiere视频转场特效全讲讲课稿

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图1-3 Doors特效图1-4 Flip Over特效 5．Fold Up（折叠）特效 这种特效用来产生一段素材像一张纸一样被折叠起来，逐渐显露另一段素材的效果，如图1-5所示。 6．Spin（旋转）特效 这种特效用来产生一段素材旋转出现在另一段素材上的效果，如图1-6所示。 图1-5 Fold Up特效图1-6 Spin特效 7．Spin Away（变形旋转）特效 这种特效与上述的旋转特效类似，不同之处在于另一段素材旋转出现时画面有透明变形，如图1-7所示。 8．Swing In（摆入）特效 这种特效用来产生一段素材如同摆锤一样摆入，逐渐遮住另一段素材的效果，如图1-8所示。 图1-7 Spin Away特效图1-8 Swing In特效

pr视频特效 转场中英对照表

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pr转场特效中英翻译

1、3D过渡（3D motion） Cube spin 立方体旋转 Curtain 窗帘 Doors 关门 Flip over 翻页 Fold up 折叠 Spin 翻转 Spin away 旋转 Swing in 内关门 Swing out 外关门 Tumble away 筋斗翻出 2、溶解（Dissolve） Additive Dissolve 附加溶解 Cross Dissolve 交叉溶解 Dip to Black 加入暗场溶解Dither Dissolve 淡入淡出 Non-Additive Dissolve 无附加溶解Random Invert 随机颠倒 3、圈入（Iris） Iris Box 盒装圈出 Iris Cross 十字形圈出 Iris Diamond 菱形圈出 Iris Points 四点圈出 Iris Round 圆形圈出 Iris Shapes 形状圈出 Iris Star 五角星圈出 4、映射（Map） Channel Map 通道映射 Luminance Map 亮度映射 5、卷页(Page Peel) Center Peel 中心卷页 Page Peel 左上角卷页 Page Turn 页面翻转 Peel Back 由中心依次向四个角翻页Roll Away 滚轴卷出 6、滑行（Slide） Band Slide 带状滑行 Center merge 向中心收缩至消失Center split 十字形撕开画面 Multi-Spin 多图旋转 Push 推出 Slash slide 斜线滑行 Slide 滑行 Sliding Bands 带状滑行 Sliding Boxes 移动带状滑行Split 撕开画面 swap 滑行交换 Swirl 盘旋 7、特技 Direct 硬切 Displace 替换 Image Mask 图片遮罩 Take 硬切 Texture 贴图 Three—D 三维 8、伸展（Stretch） Cross Stretch 交叉伸展 Funnel 漏斗收缩 Stretch 伸展 Stretch In 伸展进入 Stretch Over 伸展覆盖 9、擦除 Band Wipe 带状擦除 Barn Doors 左右推开 Checker Wipe 方格擦除 Checkerboard 积木碎块 Clock Wipe 时钟擦除 Gradient Wipe 渐进擦除 Inset 插入 Paint Splatter 泼溅油漆 Pinwheel 转轮风车 Radial Wipe 射线擦除 Random Wipe 随机擦除 Random Blocks 随机碎片擦除 Spiral Boxes 旋转擦除消失 Venetian Blinds 百叶窗 Wedge Wipe 楔形擦除 Wipe 擦除 Zig-Zag Blocks Z字形擦除 10、变焦（Zoom） Cross Zoom 交叉变焦 Zoom 变焦放大 Zoom Boxes 方格放大 Zoom Trails 拖尾缩小 1

seo中pr值什么意思

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英文版PR常用特效及翻译

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2. Change color【更改颜色】 3.Color balance HLS【色彩平衡HLS】 4. Change to color【转换颜色】 5. Luma curve【亮度曲线】 五.Distort【扭曲】 1. Offset【偏移】 2. Wave warp【波形弯曲】 3. Magnify【放大】

4. Twirl【旋转扭曲】 5. Spherize【球面化】 6. Corner pin【边角固定】 7. Lens distortion【镜头扭曲】 六.Generate【生成】 1. Circle【圆】 2. Ramp【渐变】 3. Grid【网格】 4. Lens flare【镜头光晕】 5. Lighting【闪电】

七. Generate【键控】 1. Four-Point Garbage Matte【四点蒙版键】 2. Luma【亮度键】 3. Image Matte Key【图像遮罩键】 4. Chroma Key【色度键】 5. Color Key【颜色键】 6. Blue Screen Key【蓝屏键】 7. Track Matte Key【轨道蒙版键】 8. Non Red Key【非红色键】 八. Noise&Grain【噪波与颗粒】 1. Noise【噪波】 2. Noise Alpha【通道噪波】 九. Perspective【透视】 1. Basic 3D【基本3D】 2. Drop Shadow【投影】 3. Bevel Edges【斜角边】

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PR内置特效合集

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4-5 对流传热系数关联式

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4-15 温度为90℃的甲苯以1500kg/h的流量流过直径为ф57×3.5mm、弯曲半径为0.6m的蛇管换热器而被冷却至30℃，试求甲苯对蛇管的对流传热系数。 4-16 流量为720kg/h的常压饱和蒸汽在直立的列管换热器的列管外冷凝。换热器的列管直径为ф25×2.5mm，长为2m。列管外壁面温度为94℃。试按冷凝要求估算列管的根数（假设列管内侧可满足要求）。换热器的热损失可以忽略。 4-17 实验测定列管换热器的总传热系数时，水在换热器的列管内作湍流流动，管外为饱和蒸汽冷凝。列管由直径为ф25×2.5mm的钢管组成。当水的流速为1m/s时，测得基于管外表面积的总传热系数为2115W/(m2.℃)；若其它条件不变，而水的速度变为1.5m/s时，测得系数为2660 W/(m2.℃)。试求蒸汽冷凝的传热系数。假设污垢热阻可忽略。 对流传热速率方程虽然形式简单，实际是将对流传热的复杂性和计算上的困难转移到对流传热系数之中，因此对流传热系数的计算成为解决对流传热的关键。 求算对流传热系数的方法有两种：即理论方法和实验方法。前者是通过对各类对流传热现象进行理论分析，建立描述对流传热现象的方程组，然后用数学分析的方法求解。由于过程的复杂性，目前对一些较为简单的对流传热现象可以用数学方法求解。后者是结合实验建立关联式，对于工程上遇到的对流传热问题仍依赖于实验方法。 一、影响对流传热系数的因素 由对流传热的机理分析可知，对流传热系数决定于热边界层内的温度梯度。而温度梯度或热边界层的厚度与流体的物性、温度、流动状况以及壁面几何状况等诸多因素有关。 1．流体的种类和相变化的情况 液体、气体和蒸汽的对流传热系数都不相同，牛顿型流体和非牛顿型流体也有区别。本书只限于讨论牛顿型流体的对流传热系数。 流体有无相变化，对传热有不同的影响，后面将分别予以讨论。 2．流体的特性

pr音频特效用法

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直方图统计及均衡化matlab代码

自己编的代码 Matlab中自带的函数 clc;clear all; %用自己编的函数 pic1=imread('188_2.jpg');%修改数字可以看到另一幅图片的效果pic1=rgb2gray(pic1); subplot(221);imshow(pic1);title('均衡化前的图像'); subplot(222);imhist(pic1);title('均衡化前的直方图'); L=256;%设置灰度级为256 [width,height]=size(pic1); %求nk nk=zeros(1,L); for i=0:L-1 num=find(pic1==(i+1)); nk(i+1)=length(num);

end %求pr（rk）=nk/MN pr=zeros(1,L); for i=1:L pr(i)=nk(i)/(width*height); end %pc存储的就是累计的归一化直方图 pc=zeros(1,L); for i=1:L for j=1:i pc(i)=pc(i)+pr(j); end end sk=zeros(1,L); for i=1:L sk(i)=round((L-1)*pc(i)); end %求pr(sk)，即计算现有每个灰度级出现的概率并显示在屏幕上for i=0:L-1 pr(i+1)=sum(pc(find(sk==i))); end pr %显示pr值 %替换原有图片 pic2=pic1; for i=1:L pic2(find(pic2==(i-1)))=sk(i); end subplot(223);imshow(pic2);title('均衡化后的图像'); subplot(224);imhist(pic2);title('均衡化后的直方图'); %用matlab自带的函数 pic1=imread('188_2.jpg');%先把要处理的图像读入 pic1=rgb2gray(pic1);%转化成灰度图像 %显示灰度图像与直方图 figure;

premiere视频特效--17风格化类视频特效

风格化类视频特效 风格化视频效果主要是对素材进行艺术化处理的效果。【风格化】文件夹中包含13个视频效果，分别是： 【Alpha发光】：使素材Alpha通道产生发光效果。 参数详解： 发光：设置素材发光的大小。 亮度：设置素材发光明亮的程度。 起始颜色：设置素材发光开始的颜色。 结束颜色：设置素材发光结束的颜色。 淡出：勾选选项，产生发光颜色逐渐衰减的平滑过渡效果。 【复制】：可以在画面中创建多个图像副本。 【彩色浮雕】：使素材在不去除颜色的基础上产生立体浮雕效果。 参数详解： 方向：设置浮雕效果的方向。 起伏：设置浮雕效果的尺寸大小。 对比度：设置浮雕效果的对比度。 与原始图像混合：设置与原始素材的混合程度。 【抽帧】：通过改变素材的颜色层次，从而调整素材的颜色效果。 【曝光过度】：模拟相机曝光过度的效果。 【查找边缘】：利用线条效果将素材对比高的区域勾勒出来。 【浮雕】：使素材产生立体浮雕效果。

【画笔描边】：使素材模拟出笔触绘画的效果。 参数详解： 描边角度：设置画笔描边的角度。 画笔大小：设置画笔尺寸的大小。 描边长度：设置每个描边笔触的长度大小。 描边密度：设置描边的密度。 描边浓度：设置描边笔触的随机性。 绘画表面：设置笔触与画面的位置和绘画的进行方式，包括【在原始图像上绘画】、【在透明背景上绘画】、【在白色上绘画】和【在黑色上绘画】4种方式。 与原始图像混合：设置与原始素材的混合程度。 【粗糙边缘】：使素材边缘变得粗糙。 【纹理化】：在当前图层中创建指定图层的浮雕纹理的效果。 【闪光灯】：在素材中创建有规律时间间隔的闪光灯效果。 【阈值】：可以调整素材为黑白效果。 【马赛克】：可以调整素材为马赛克效果。

AePr视觉特效和转场BCC插件包Continuum插件中英文对照表

BCC插件中英文对照表 一、BCC 3D Objects三维物体 BCC Extruded EPS 内置图形挤压成3D图形BCC Extruded Spline挤压样条曲线 BCC Extruded Spline Curves挤出的样条曲线BCC Extruded Text挤压文本 BCC Extrusion Bevel Curves挤压锥曲线BCC Extrusion Side Curves挤压边曲线BCC Extrusion T ext Paths挤压文本路径BCC Layer Deformer层变形 BCC Title Studio 文字标题效果插件BCC Type On Text类型文本 二、BCC Art Looks视觉艺术 BCC Artist's Poster招贴画 BCC Bump Map凹凸贴图 BCC Cartoon Look漫画 BCC Cartooner艺术画效果 BCC Charcoal Sketch木炭画 BCC Halftone中间色 BCC Median中间的

BCC Pencil Sketch素描 BCC Posterize色调分离 BCC Spray Paint Noise喷漆噪声BCC Tile Mosaic马赛克瓷砖 BCC Water Color水彩画 三、BCC Blur滤镜 BCC Directional Blur方向模糊滤镜BCC Fast Lens Blur快镜头模糊BCC Gaussian Blur高斯模糊BCC Lens Shape透镜 BCC Motion Blur动态模糊 BCC Pyramid Blur金字塔模糊BCC Radial Blur径向模糊滤镜BCC Spiral Blur旋转模糊 BCC Unsharp Mask反锐化模糊BCC Z-Blur 四、BCC Color & Tone色彩与色调BCC 3 Way Color Grade色彩分级BCC Brightness-Contrast亮度对比BCC Color Balance色彩平衡BCC Color Correction色彩校正BCC Color Match色彩搭配 BCC Colorize着色

Premiere全部内置视频特效解析汇报

Premiere 置视频特效解析 一、变换类特效 1.垂直保持：【垂直保持】特效可以使图像在垂直方向上滚动，但滚动速度速度将要快。 2.垂直翻转：运用该特效可以将画面沿中心翻转180度，产生垂直翻转效果。 3.摄像机视图：该特效可以模拟摄像机在不同的角度对图像进行拍摄所产生的视图效果。 单击该特效右侧【设置】按钮，将弹出摄像机视图设置对话框。该对话框中的参数与特效控制中的参数相同。

【经度】设置摄像机拍摄时的垂直角度 【纬度】设置摄像机拍摄时的水平角度 【垂直滚动】让摄像机绕自身中心轴转动，使图像产生摆动的效果【焦距】设置摄像机的焦距，焦距越短视野越宽 【距离】设置摄像机与图像之间的距离 【缩放】设置对图像的放大或缩小程度 【填充】设置图像周围空白区域填充的色彩 【填充Alpha通道】：勾选该复选框，使图像产生一个Alpha通道【复位】单击该按钮，将所有设置恢复到默认 4.水平保持：该特效可以使图像在水平方向上产生倾斜 【偏移】用来设置图像的水平偏移程度

5.水平翻转：该特效可以将画面沿垂直中心翻转，产生水平翻转效果 6.羽化边缘：该特效可以使图像边缘产生羽化效果 【数量】用来设置边缘羽化的程度 7.裁剪：该特效根据指定的数值对图像进行修剪，但裁剪可以使剪切后的图像进行放大处理 【左侧】、【顶部】、【右侧】、【底部】：分别指图像左、上、右、下4个边界，用来设置4个边界的裁剪程度 【缩放】勾选该复选框，在裁剪时将同时对图像进行缩放处理 二、图像控制类特效 1.灰度系数（Gramma）校正：该特效可以通过改变图像中间色调的亮度，实现在不改变图像高亮区域和低暗区域的情况下，让图像变得更明亮或更暗 【灰度系数（Gramma）】用来修正颜色的Gramma值，值越大，图像越暗；越小图像越亮 2.色彩传递：该特效可以将图像中指定颜色保留，而其他颜色转化成灰度效果