A Typology of Relationships Between Telecommunications and Transportation

A Typology of Relationships Between Telecommunications And Transportation

Patricia L. Mokhtarian

June 1990 Reprint, No. 82

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Authors of papers reporting on UCTC-sponsoredresearch are solely responsiblefnr their content. This research ’,’,’as supportedby the U.S. Deparhnentof Transportation and the California Slate Departmentof Transportation,neither of whichassumes liability for its content or use. A Typology of Relationships Between Telecommunications and Transportation

Patricia L. Mokhtarian

Institute of Transportation Studies University of California at Davis

Reprint, No. 82

Transportation Research Voi. 24A, No. 3, pp. 231-242, 1990

The University of California Transportation Center University of California at Berkeley 7h~n.Ra.-A, Vol. 24A,No. 3, pp. 231-242,1990 0191-2607/90$3.00+.00 Pr~uMin Great Briuun. © 1990Pergamon Press plc

A TYPOLOGYOF RELATIONSHIPS BETWEEN TELECOMMUNICATIONS AND TRANSPORTATION

PATRICIALYON MOKHTARIAN Departmentof Civil Engineering,University of California, Davis, CA95616, U.S.A. (Received20 April 1989;in revised form 23 October1989)

Abstract--This paper defines the relationship between telecommunications and’ transportation, by ex- panding on linkages already identified in the literature, by identifying additional relationships, and by putting these relationships into a robust conceptual framework. There are conceptual, physical, analytical, and regulatory parallels between telecommunications and transportation. Telecommunications affects the demand for, and supply of, transportation- and vice versa. In the broadest sense, all communication requires transportation in order to occur: transportation either of people, of objects, or of electronic impulses. In other words, communication takes place via one or more of those three modes. It is suggested that "communication breeds communication." That is, the easier it is to communicate (whether through travel or telecommunications), or the more that one or another form of communication takes place, the more that communication as a whole is stimulated. The relative shares of each of the three modes of communication may vary as one mode partially substitutes for another, but the absolute amounts of communication via each mode are likely to increase. Twoempirical studies are summarized, one illustrating that teleconferencing increased travel, the other illustrating that telecommuting decreased travel. Other implications for transportation planning are highlighted.

1. INTRODUCTION and (iv) indirect, long-term impacts (e.g., telecommunications mayultimately affect land use, which The relationship between telecommunications and will affect travel). Salomonrefers to (iii) as first-order transportation has been discussed in the transporta- complementarityand to (ii) as second-order comple- tion literature (and that of the related disciplines of mentarity. energyand air quality) for at least 25 years (see, e.g., All these relationships refer to the impactof tele- Harkness, 1977; JALAAssociates, 1983; Jones, communications on transportation. However, the 1973; Khan, 1976; Kraemer, 1982; Kraemer and converse set of relationships-that is, the impacts of King, 1982; Lathey, 1975; Memmott,1963; Nilles et transportation on telecommunications-are also im- d., 1976; and Obermannet aL, 1978). The energy portant. The purpose of this paper is to define the crisis Of the early 1970s promptedmuch of the initial relationship between telecommunications and trans- research into the substitutability of telecommunica- portation, by expandingon the linkages already iden- tions for travel. As the publicly perceived urgencyof tified, by identifying additional relationships, and by the energy crisis wanedsomewhat in the early 1980s, putting these relationships into a robust conceptual so too did research into energy conservation mea- framework. This will lead to a broader, more com- sures including telecommunicationssubstitutions. plete understanding of the potential impacts of tele- The mid-to-late 1980s, however, have seen a resur- communicationson transportation-and vice versa. gence of interest, amongtransportation planning The following section discusses certain parallels academiciansand especially practitioners, in the po- between telecommunications and transportation. tential impacts of telecommunicationson their field. Section 3 recasts the four relationships listed above Becauseof the persistent attractiveness of reducing into the familiar economic frameworkof supply and travel, whether to save energy, decrease congestion, demand, and presents examples of supply-demand or improveair quality, it is not surprising that most relationships betweenthe two areas. Section 4 elabo- of the relevant literature on the transportation de- rates on the conceptual frameworklinking communi- mandside has concentrated on the substitution po- cations and transportation. Section 5 describes the tential of telecommunications for travel. However, findings of two empirical studies of the impact of other relationships between the two fields have not telecommunications on the demandfor travel. The escaped notice, and indeed the roots of those rela- concluding section summarizes some implications tionships date back muchfurther than 25 years, as for the transportation planning profession. will be discussed later. The literature (Salomon,1986; ECMT,1983) identifies four different kinds of relationships: (i) substitution (e.g., telecommunications 2. PARALLELS BETWEENTELECOMMUNICATIONS decreases travel); (ii) enhancement(e.g., telecommu- AND TRANSPORTATION nications directly stimulates travel); (iii) operational There are a numberof interesting parallels be- efficiency (e.g., telecommunicationsimproves travel tween telecommunicationsand transportation. First, by makingthe transportation system more efficient); there are conceptual parallels. Theseare discussed at 231 232 P. L. MOKHTARIAN greater length in Section 4; somebrief observations Southern NewEngland Telephone and the CSX are made here. Telecommunications may be thought railroad holding company.Its chief asset is an of as the transportation of information. In the tele- all-fiber network strung largely along CSX communicationstrade literature, it is quite common rights-of-way. Based in Rockville, Maryland, to come across phrases like, "telecommunications Lightnet handled $100 million of long-distance highway, .... information pipeline," "voice and data business in 1987. traffic." "Teleports" are to information transporta- (iii) The Williams Telecommunications Group (now tion what "airports" and "seaports" are to passenger member of the National Telecommunications and freight transportation. Eventhe word "bus," to Network consortium) began by using abandoned stretch the point, has specialized meaningin local gas pipelines throughout the Midwestas conduit area network (LAN)architecture, as does the word for fiber-optic cables (Keppel, 1988). "bridge" for audioconferencing. (iv) The Washington(DC) Metropolitan Area Transit Conversely,it is axiomaticthat transportation is a Authority (WMATA)has authorized a regional derived demand. The demandfor freight travel de- telecommunic,ationscarrier, Institutional Com- rives from the spatially dispersed demandfor goods. munications Company,to install fiber optic ca- Passenger travel is undertaken not for its ownsake ble throughout its subway system. In return, (by and large), but to participate in an activity at the WMATAreceives a portion of network capacity trip destination. Often the main purpose of trans- to use for its own telecommunications needs porting those goodsor participating in that activity is (Killette, 1987). to communicate something. Thus, communication outside the direct range of our senses cannot take There are analytical parallels betweentelecommu- place without transporting something-either a per- nications and transportation. By nature, both fields son, a physical object such as a letter or photograph, involve networks. Each type of network can have or electrons or radio waves. links of different capacities, can permit different There are physical parallels betweentelecommuni- speeds of travel, can be designed for different kinds cations and transportation: telecommunicationsnet- of traffic. In transportation, for example,link capac- worksare oftea superimposedon existing transporta- ities range from that of say, a two-lane country road tion networks.These physical parallels are at least a to that of a 12-lane urban freeway; in telecommuni- century-and-a-haifold: the first uses of the telegraph cations, capacities range from that of the twisted included facilitating the operation of rail systems, copper pair of Plain Old TelephoneService, to those and consequently early telegraph networks often fol- of "broadband"media such as satellites or fiber-optic lowedrailroad rights of way(see, e.g., Kieve, 1973; cable. The concept of "impedance" has been trans- Harlow, 1936). Today, local telephone systems and ferred from electrical networksto transportation net- cable television delivery systems normallyfollow city works. streets and roads. The relationship betweenthe trans- Since in manykey respects "a network is a net- portation and the telecommunicationsentity in these work," several classes of analytical techniques can cases is primaril.x’ that of regulator to regulated; ac- apply as well to telecommunicationsas to transporta- cess to the public rights of wayis typically regulated tion networks. Queuing theory is an obvious exam- under a state or local franchise. ple, which has been used to model the behavior of In recent years, other financial partnerships (as cars on streets and the utilization of other transporta- opposed to largely regulatory relationships) have tion service facilities as well as the distribution of arisen betweentelecommunications service providers telephone calls and the sizing of telecommunications and transportation entities, typically giving the tele- facilities (see, e.g., Giffin, 1978). Mathematicalpro- communicationsprovider the right to lay fiber optic grammingtechniques (such as network optimization cable for regional or long-distance communications and integer programming)have also been applied in in the transportation right of way. This partnership both fields (Ford and Fulkerson, 1962). maysimply be a lessor-lessee relationship (perhaps in Finally, there are regulatory parallels betweentele- which the lessor, the transportation agency or com- communicationsand transportation. Historically, pany, is also granted somecapacity on the telecom- segmentsof each industry have been considered natu- munications network for its own communications ral monopolies, although as Kahn(1971, pp. 2, 10) purposes), a joint venture betweenthe two parties, or and others point out, this designation is open to de- full-fledged ownershipof one by the other. The fol- bate in general, and even if it is granted for one point lowingexamples serve partially to illustrate the range in time, it maynot hold at a later point due to tech- of existing financial partnerships involving co-loca- nological advances. Certain kinds of service provid- tion of networks: ers in each industry are considered "commoncarriers," and therefore in some respects have been (i) Perhaps the most well-known modern example regulated similarly. (There is, however,at least one of this physical parallel is U.S. Sprint, whichwas important regulatory difference betweentransporta- originally ownedby Southern Pacific Railroad tion and telecommunications commoncarriers. The and initially followedSP rights of way. Reed-Bulwinkle Act of 1948 conferred immunity (ii) Lighmetis a five-year-old joint venture between from anti-trust regulation on transportation carriers Telecommunicationsand transportauon 233 jot airports wherethey can catchplanes to their final desti- [see Chapters 20 and 22 of Sampsonet aL, 1985], nations, the small long-distancecompanies carry their cus- while the telecommunications industry enjoyed no tomers’calls to a metropolitanarea wherethey are switched such protection. The anti-trust suit launchedin 1974 onto the networkof another company...(Keppel, 1988) by the Justice Departmentagainst AT&Tthat led to the divestiture of the Bell Operating Companiesin 1984was only the latest in a series of antitrust actions 3. SUPPLY-DEMANDRELATIONSHIPS BETWEEN targeting AT&Tthroughout its existence-see, e.g., TELECOMMUNICATIONSANDTRANSPORTATION Brock, 1981.) The conceptual and physical parallels discussed In the United States, regulatory jurisdiction for above suggest another perspective from which to telecommunications and transportation carriers of- view telecommunications/transportation relation- ten falls under the same governmentalbody, such as a ships: the economic perspective of supply and de- Public Service Commissionor Public Utilities Com- mand. That is, telecommunications affects the de- mission in manystate administrations. At the local mandfor, and supply of, transportation--and vice level, until the creation of a newDepartment of Tele- versa. The following subsections provide somespe- communicationsin 1985, cable television franchise cific examples of the impacts of transportation on administration in the City of Los Angeles resided telecommunications demandand supply, and the im- under the Department of Transportation (DOT). pacts of telecommunications on transportation de- Aside from the physical parallels betweenthe cable mandand supply. The latter set of impacts is natural- television networkand city streets referred to above, ly of most direct interest to the transportation the rationale was that DOT’slengthy experience in profession. However,it is also important to be aware franchising taxi service should be largely transferable of the implications of the transportation environ- to franchising cable television service. ment for the telecommunicationsindustry, especially Segments of both telecommunications and trans- in view of the feedback relationships discussed portation industries are undergoingextensive deregu- below. lation, as well. Rate of return as the basis for price regulation has been weakenedor eliminated for vari- 3.1 The impact of transportation on the ous segments of the transportation industry (see demand for telecommunications Chapter 22 of Sampsonet al., 1985, for a general A number of telecommunications products and discussion), and is nowapparently undergoing simi- services are directly targeted to segmentsof the trans- lar erosion in the telephone industry (see, e.g., Ma- portation industry; hence, transportation may be son, 1989a, 1989b). said to stimulate the demandfor those products and There are certainly issues arising out of deregula- services. Obvious examples include nearly all forms tion that are commonto both industries. One such of mobile communications-that is, those forms issue is "cream-skimming,"referred to in the telecom- which are vehicle-based (as somefuture mobile communications industry as "bypass." In a regulated munications devices become more person-based, public utility with an expressed or implied mandate along the lines of Dick Tracy’s two-waywrist radio, for "universal service," the provider typically subsi- the link to transportation, at least motorizedtrans- dizes the cost of providing service to uneconomical portation, will becomemore tenuous). market segments by charging some people more than These products and services maybe operations- their fair share of the costs wouldindicate. In a de- related, largely arising from the need for information regulated business, a competitor can identify a seg- on, and control of, the movementof passengers and mentof the market for whichit is profitable to offer cargo. These include: navigational devices; tracking/ comparable service at a lower price. As customers location equipment; dispatch services; and ship-to- migrate to the competitor, revenuesto the initial pro- shore and ground-to-air capabilities. A historical ex- vider maybe reduced to the point that it can no ample is again the development of the telegraph, .longer support the uneconomical segment of the which was partly fueled by the need for "real time," market. Hence, deregulated airlines cancel unprofit- reliable communicationon the status of trains. able routes, and Bell Operating Companiescry that Or these products and services maybe related to their point-to-point competition will erode their sub- personal communications, such as: Airfone and scriber base to the point of jeopardizing universal Railfone services, permitting plane or train passen- service. Somewhatsimilar principles are involved in gers to makephone calls in transit; and cellular ra- the debate over whether/when public mass transit dio, or car phones. should be privatized. Despite the apparently symbiotic relationship be- The regulatory parallels have not escaped popular tween telecommunications and transportation entit- notice. A Los Angeles Times article analyzing the ies, their interests do not always coincide. To illus- success of niche telecommunications marketing trate the potential difference in perspective between states, telecommunications and transportation service providers, consider the impact of commutecongestion [Regionaltelecommunications carriers] are, in someways, on car phone demand.The longer people are stuck in analogousto the smallairlines that developedafter deregu- lation of that industryto servemarkets abandoned by larger traffic, the more they are likely to use their car carriers. Just as these smallairlines haul passengersto ma- phones. Whatis a major crisis to the transportation 234 P, L. MOKh’TARtAN planner is a major windfall to the mobile telephone tions to transmit a cultural, athletic, or other service provider. It is probably no coincidence that entertainment activity to multiple locations. Tel- gridlocked Los Angelesis heralded as the largest cel- evised live events qualify as tele-entertalnment, lular radio market in the world (Kim, 1987), although as do cable TVmovies. The lowly radio also fits other factors besides congestion (such as occupation this category. Videocassettes are an interesting and income)certainly comeinto play in affecting the hybrid. Theydo not involve long-distance trans- demandfor car phones. mission and so mayonly loosely be considered "tele’-entertainment, but their effect of diffus- 3.2 The impact of transportation on the ing the viewing audience into numerous small supply of telecommunications entities rather than one large one is comparable Someexamples of this relationship have been re- to that of TVmovies (whether broadcast or ca- ferred to in Section 2, in the use of transportation ble). Onthe other hand, unlike TVmovies, vide= rights of way to construct fiber optic (and other) ocassettes typically require a trip to purchaseor networks. It can be safely concluded that at least rent them, suggesting that their transportation somestart-up long-distance phone companies proba- impacts may be closer to those of in-theater bly would not be able to exist independently of a movies than to broadcast or cable programming. transportation partner to provide a ready-maderight Those impacts will by no means be identical, of way, although there are notable counterexamples however:a trip to acquire a videotapeis likely to such as MCI.Another exampleis the impact of space be quite different in time, pattern (i.e., the kinds transportation on the supply of satellite communica- of other activities, if any, linked to the trip), and tions capacity. possibly space than a trip to the movies. This exampleserves to point up the complexity of the 3.3 The impact of telecommunications on the interactions between communicationsand trans- demandfor transportation portation. A great deal has been written on this relationship, Several special cases of teleconferencing deserve particularly on the substitutionary potential of tele- individual mention: communica:!onsfor travel. A list of somecurrently practiced substitution applications includes the fol- (vi) Tele-education."Distance learning, as it is some- lowing. times called, involves using satellite, micro- wave, or cable television systems to transmit (i) Telecommuting: working at homeor other re- classroom instruction to one or more remote mote location, with telecommunicationslinks to locations. This telecommunicationsapplication a central office. is quite common;industry experts believe that (ii) Teleconferencing: meeting at multiple locations, around 80%of all teleconferencing is for edu- with audio, video, and/or data links among cation or training purposes (Portway, 1988). sites. Yele-educationis being used to: transmit entire (iii) Teleshopping: using computer- or television- degree programsfrom accredited universities to based services to obtain information about, and worksites; share specialized teachers among sometimes to purchase, products (see Salomon multiple grade schools in a metropolitan area; and Koppelman.1988). Telemarketing, both in- transmit advanced placement courses from col- bound (a customer calling an "800" number to lege campuses to high school campuses; pro- place an order, typically promptedby a mail or vide instruction at home; and reach into rural television advertisement) and out-bound (the areas. systematic telephoning of a target market to so- (vii) Tele-medicine: Improbableas it mayappear at licit orders for a product or service), maybe con- first glance, somemedicine can effectively be sidered a form of teleshopping. Teleshopping practiced remotely. Video and data links make maynot substitute for a shoppingtrip per se. It it possible for health professionals in rural often either replaces a mail-order catalog choice parts of the country to transmit video images, or represents an impulse purchase, or both. Nev- X-rays, and other informationto a specialist in ertheless, as videotex services becomemore com- a metropolitan area, and receive an intelligent mon. an increasing number of shopping trips diagnosis and treatment regimen without a will be replaced. lengthy (and in some cases medically danger- (iv) Telebanking: using a computer with modemand/ ous) trip for the patient (The Futurist, February or a touch-tone telephone to perform banking 1985). Conversely, the sameoperation that can transactions such as payingbills and transferring be seen in-hospital via closed-circuit television moneybetween accounts. Automatedteller ma- can be transmitted to any number of outside chines (ATMs)may also be considered a form sites for maximumteaching effectiveness. telebanking, especially to the extent they are (viii) Tele-justice: Routine functions such as deposi- found in convenient places not requiring a sepa- tions and arraignments can now be handled rate trip to access. through videoconferencing or even audiocon- (v) Tele-entertainment: the use of telecommunica- ferencing links betweenthe courthouse and the Telecommunicationsand transportation 235 prison. This capability eliminates the costs and (ii) Short-term indirect: The time saved by telecom- hazards of transporting prisoners back and munications substitution for travel maybe used forth without compromising due process. The to makeother trips. Thus, for example, compa- years 1988 and 1989 saw perhaps the first case nies with in-house videoconferencing facilities of international tele-justice, in whichtwo Brit- often do not find a reduction in travel costs, as ish residents served as witnesses in a U.S. trial teleconferenced meetings are supplemented by through a videoconferencing arrangement be- other (perhaps moredesirable or moreessential) tween a London hotel and the Milwaukee trips. courtroom (Communications News, February (iii) Long-term: Telecommunications infrastructure 1989). and services maylead to long-term changes in land-use patterns (e.g., moredispersed residen- The above applications deal primarily with the tial and employmentlocations) that mayin turn replacement of passenger transportation by telecom- result in longer trips or moretravel in general. munications. Freight transportation can also be sub- stituted for by telecommunications, however. Elec- tronic data transmission using modemscan substitute The substitutionary and complementary aspects of the relationship between transportation and telecom- for physical shipmentof information products. Satel- munications will be discussed more generally in Sec- lite transmission of newspapers such as the Wall tion 4. Street Journal and USAToday to widely dispersed printing plants substitutes for centralized shipping 3.4 The impact of telecommunications on the and delivery networks. Manydocuments now trans- supply of transportation mitted by facsimile would a few years ago have been sent by overnight or conventional mail, although Telecommunicationscan increase the effective level of service of a transportation system by supporting there is also evidence that fax has pilfered market moreefficient use of existing networks. This is by no share from another telecommunicationsservice: elec- means a development confined to recent advances in tronic mail (Thomas,1989). telecommunications technology: Beniger (1986) Despite the seeminglyextensive list of trip substi- traces the roots of the so-called "Information Revolu- tution applications, telecommunications can also tion" to a "crisis of control" in the production,distri- serve to stimulate travel, as indicated in the Introduc- bution, and consumption of goods and services in tion. Mokhtarian (1988) and others point out that the middle of the last century. Examplesof telecom- this stimulationeffect can arise in several ways: munications-based control or feedback systems sup- (i) Short-term direct: Telecommunications can porting goods and people movementinclude: (i) make information about people and activities highwayemergency call boxes, permitting quicker re- muchmore accessible than would otherwise be moval of accidents; (ii) changeable messagesigns possible. This information maycreate the desire route traffic around major incidents; (iii) real-time to travel to participate in those activities and traffic signal synchronization and priority override; interact with those people. Further, as the ob- (iv) CBradios, permitting prompt accident reporting verse of the point that transportation stimulates and route diversion; (v) freeway rampmetering; (vi) the demandfor mobile telecommunications, the remote video surveillance of freeway ramps and high- ability to communicatewhile traveling mayitself occupancy vehicle lanes, permitting more effective stimulate moretravel, or at least inhibit attempts enforcementand incident managementabilities; (vii) of transportation planners to reduce travel. The in-vehicle navigation devices; (viii) automatedvehicle availability of a car phone, for example, may and guidewaytechnologies; (ix) radio determination discourage a commuter from adopting vehicle satellite systems (RDSS), permitting tracking and trip reduction strategies such as transit or ri- control of cargo at any point in the shipment (Dow, desharing. One enterprising transportation pro- 1989); (x) electronic documenttransfer amongship- vider in Los Angeles jumped into this market- pers, customers, and Customsofficials (Feldman, place vacuumwith luxury shuttle vans equipped 1986); (xi) voice mail systems for truckers, reducing with cellular phones, VCRs, and faxes (Bush, the difficulty of communicationbetween dispatchers 1988), but the economicviability of such a ser- anddrivers on the road; and (xii) microwavelanding vice remains unproven. This particular service systems for aircraft, which the Federal Aviation Ad- was terminated a few months after opening ministration has suggested can provide up to 50% (Wolf, 1989). more capacity at congested airports than convention- On the other hand, the availability of kiosks al instrument landing systems (Airport Highlights, with real-time route and schedule information 1989). might stimulate transit usage. Andproposed vi- A numberof these elements(including, at least, ii, deotex systems for promoting ad hoc carpoo[ iii, v and vii) are being combinedin the three-year, formation (Ferrell, 1984; Hawaii Departmentof $1.6 million, "Smart Corridor Telecommunications Planning and Economic Development, 1984) Demonstration Project," for the Santa MonicaFree- might increase both ridesharing demand and way Corridor in Los Angeles. Also known as the supply. Pathfinder Project, it is authorized by State Assem- 236 bly Bill 1239, and funded by FHWA,Caltrans, and portation maytake one or more of three forms: (i) General Motors (Gherardi, 1989). The project will transportation of people, to meet face-to-face (or test whetherthe integration of these and other strate- within earshot); (ii) transportation of objects, such gies significantly decreases congestionin that corri- letters, books, newspapers, audio- or videotapes, dor. The six-year, $56 million, Programon Advanced floppy disks, and so on; and/or (iii) transportation Technology for the Highway (PATH), conducted electronic impulses, either in the form of electrical the University of California, is exploring a numberof current along copper wires, coaxial cable, or optical elements relating to automatedvehicles and roadways fiber, or in the form of radio wavesthrough the air. (TR News, July-August 1989, p. 19; Kanafani and The situation is not symmetric, however.The role Parsons, 1989). Similar studies are already well un- of transportation in all forms of communicationis derway in Europe, under the seven-year, $1 billion that of a sine qua non: the transportation, in effect, Promotheusproject (Beck et al., 1988). constitutes the act of communication.On the other It is no accident that someapplications appear hand, the role of cc~mmunicationsin someforms of here as well as in the list of examplesof ways that transportation is ancillary or even nonexistent. Even transportation affects the demandfor telecommuni- if it is a necessary adjunct to the transportation, it cations. There is a feedback mechanism at work does not itself constitute that transportation. In the amonga numberof these relationships. For example, case of transporting people, leisure travel does not transportation generates the demandfor transporta- have communication as its primary purpose, al- tion-oriented telecommunications products and ser- though some communicationwill almost inevitably vices, and those products and services in turn affect be associated with it. Mostfreight transportation has supply of and demandfor transportation. the delivery of goods rather than information as its The relationships discussed in this section maybe primary aim, the exceptions being the kinds of infor- summarizedby the diagram in Figure 1. The vertical mationfreight identified in (ii) above. Andelectronic arrows represent traditional supply/demandrelation- impulses such as electromagnetic radiation do not ships for a single category of"goods." The horizontal always include meaningful information. Microwaves, arrows represent the cross-category relationships de- for example,can either transmit data or cook food. scribed above. The absence of crossover arrows be- If transportation and telecommunications are tween, for example, transportation demandand tele- simply ahernate forms of communication,then their communicationssupply, is not meant to suggest that relationship to each other (i.e., whethersubstitutes those relationships do not exist, but rather that they or complements)is affected by what is happening to tend to be indirect: for example, transportation de- communicationin general. It has been hypothesized mandaffects telecommunications demand which in (e.g., Salomon,1986) that communicationis increas- turn affects telecommunicationssuppl); ing exponentially. This suggests that "communication The relationship between transportation demand breeds communication."That is, the easier it is to and telecommunications demandgoes beyond trans- communicate(whether through travel or telecommu- portation giving rise to niche telecommunications nications), or the more that one or another form of products, or telecommunications products making it communicationtakes place, the more that communi- moreattractive to travel. Transportation also gener- cation as a whole is stimulated. This implies that ates niche food products such as airline meals, but increases in travel will generally lead to increases in the telecommunications/transportation interaction is the combination of personal travel, telecommunica- more intimate than that. In manycases, transporta- tions, and transportation of information products, tion can accomplish the same purpose as telecommu- and that increases in telecommunications will also nications-they are conceptually ,,wo facets of the generally lead to increases in the combinationof the same idea. Thus. they can either be competingmodes same three areas. The relative shares of each of the of communication(substitutes), or they can synergis- three modes of communication may vary as one tically support each other in increasing all forms of modepartially substitutes for another, but the abso- communications(complements). This relationship lute amounts of communication via each mode are explored morefully in Section 4. likely to increase. Figure2 illustrates this principle of potentially simultaneous substitution and generation: in the example shown, the actual amount of 4. THE CONCEPTUAL RELATIONSHIP BETWEEN personal travel increases as part of a general expan- TELECOMML’NICATIONS AND TRANSPORTATION sion in communication, even though its share as a Some conceptual parallels between telecommu- communicationmode declines. It is the combination nications and transportation were briefly advanced of these two counteracting forces that makes it so in the preceding sections. It is useful to expandthe difficult to determine the net impact of telecommuni- discussion slightly, to explore the relationships cations on transportation (or conversely) in any par- among communications, telecommunications, and ticular context. transportation. The following historical, anecdotal, abstract, and In the very broadest sense, all communications hypothetical examplesof this principle serve to illus- require transportation in order to occur. That trans- trate the rangeof possibilities: Telecommunicationsand transportation 237

~INCREASI~ EFFICIENCY ]

RIG~F-WAY

Fig. I. Supply-demandrelationships between telecommunicationsand transportation.

Fig, 2. Relative substitution amongcommunications modes, simultaneous with absolute expansion of all modes. 238

(i) In the 1960s, a prototypical videotelephonesys- not be taking the class at all if it were only tem was installed between two NewJersey Bell offered on campus. Muchof tele-entertainment Laboratories locations about 100 miles apart. (e.g., a televised concert, play, or sports event) Before the videophone,a researcher at location would have to be considered new entertainment Awould call a colleague at location B to discuss opportunities for the largest part of the view- the latest brainstorm. "That’s interesting," the ing/listening audience rather than alternative colleague would say. "The next time I’m over waysof participating in existing opportunities. there HI drop by and we can discuss it some And it has been found that teleconferencing more." After the installation of the video link, maylead to more meetings, and more people at the researcher wouldcall the colleague and say, a given meeting, than would be the case other- "Look what I’m doing." "Amazing!" the col- wise (Green and Hansell, 1984). league wouldreply. "I’11 be right over!" Use of (vi) Even while telecommunications stimulates the the companycar fleet for inter-site travel in- demandfor rhore telecommunications, it may creased appreciably following the introduction increase travel as well. Asindicated in the pre- of the videophone(Ross, 1987). vious section, this maybe a short-term effect (ii) It is rather profoundthat the first wordsspoken either direct or indirect in nature, or a long- by Alexander GrahamBell into the telephone he term effect related to changesin land use. had just invented were, "Watson, comehere, I (vii) Companies(such as Federal Express, Texas In- want you" (de Sola Pool, 1977, p. 12). Even struments, and Apple Computer)with extensive though the trip was just a few feet downthe hall in-house satellite videoconferencing networks in this case, the very first use of that mostuni- report an unexpected stimulation effect on the versal telecommunications product, the tele- demandfor business-related videotapes. For ex- phone, was to generate a trip for the purpose of ample, the Texas Instruments sales force wanted face-to-face communications. copies of a press conferenceheld by satellite, so (iii) While the impact of facsimile machines on that it could provide the information to’custom- overnight pack~.ge delivery services has been ers. This led to the creation and distribution of palpable (Clarkin, 1988), analysts speak 5,000 videotapes. "This wouldn’t have hap- terms of slowed growth rates for the delivery pened before we had our satellite network,"a TI companies, not loss of business in absolute spokesmanstated. "Our demandfor tape is in- terms. Again, the expansion of the total market creasing by an order of magnitude." Echoes more than compensates for relatively small Federal Express, "Seeing programs by satellite changesin market share. seems to increase the demandfor programming (iv) Thecongestion, energy, and air quality benefits overall" (Amato,1989). of new urban freeways are under debate (see, (viii) Assessments of the impacts of new communica- e.g., Newmanand Kenworthy, 1988; Newman, tions technologieson the old are often, in retro- et al., 1988; and Plane, 1986, pp. 389-90). On spect, laughably off the mark. The "paperless the one hand, ceterisparibus, increasing capaci- office" waswidely heralded a few years back, as ty will reduce congestion, which will improve a probable consequenceof the introduction of air quality and decrease fuel consumption.But personal computers into the workplace. In- newfreeways do not keep all other things equal. stead, there has been a paper explosion, with no The)’ induce new demand (the argument goes) slowing downin sight. Similarly doomsayers by makingtravel in that corridor comparatively predicted the demise of radio and newspapers very attractive-that is, until the new freeway with the introduction of television, whereasin fills up (whichis often the day it opens), all the fact the old forms of communicationare flour- old freeways fill back up, and overall conges- ishing comfortably beside the new. Onthe other tion is at least as bad, only at higher levels of hand, there was early concern that the telegraph demand. It is also argued that new freeways wouldcompete "too" effectively with the postal promotemore dispersed (therefore less energy- service (Harlow, 1936). Instead, of course, the efficient) land-use patterns and discourage the mail has survived while the telegraph has been use of masstransit. eclipsed by later technology. Obviously, some (v) Along the samelines, the availability of tele- forms of transportation (horses, clipper ships) communicationsservices will promotemore tel- and telecommunications (telegraph) have and ecommunications. Consider the examples of will becomeobsolete or reduced to hobbyist potential trip substitution applications listed in proportions (the futurist Paul Saffo recently the previous section. In man)’ cases they may suggested that the same thing may happen to not be fulfilling existing communicationsde- books as we know them-Koenenn, 1989), but mand through telecommunications instead of the record of predicting such changes is mixed travel, but creating new demandthat will be at best. fulfilled through telecommunicationsor not at all. Impulseteleshopping is one example.In the It is perhaps humannature to think of innova- case of tele-education, manyparticipants would tions in terms of howthe)’ can help us do old things Telecommunicationsand transportation 239 differently. Soon, however, it becomesapparent that novelty effect, or because the meeting actually ful- they also help us do new things. Thus, automobiles filled its objective of being moreconvenient for more started out as "horseless carriages," and telephones people, or (most probably) some of both, telecom- were originally thought of as good substitutes for municationsincreased travel. messengerboys (ECMT,1983). Indeed they were, and The study concludedthat the observed increase in a good deal more besides! travel should not necessarily be a cause for despair. In The point is that it is dangerousto count on the the first place, the benefit of achieving improved substitution of telecommunications for transporta- communicationcan be viewed as outweighing the dis- tion in any but a relative sense. The substitution po- advantageof creating additional travel. In the second tential is genuine, of course. As the ECMT(1983, p. place, even the additional travel that took place was 79) report puts it, "the simple reductio ad absur- not as troublesome as it might seem. Because of the dum-what would our roads be with no tele- teleconference, the travel was redistributed in time phone?-is sufficient proof if proof were needed." and space to less congested parts of the transporta- Nevertheless, that same examplealso illustrates the tion system. It is possible that the net impact on synergistic effect of telecommunicationsand trans- congestion was negligible or even positive. portation: had the telephone not been invented, the entire economywould be drastically different than it 5.2 SCAGtelecommuting pilot is today, and muchof the transportation we are asked It has been speculated that newtravel generated by to envision would simply never have been generated. telecommutingcould largely obviate the benefits of the commutetravel saved. Salomon (1985) suggests that the synergistic effects of multiple telecommuni- 5. EMPIRICALEXAMPLES OF THE cations applications in the homemight lead to in- TELECOMMUNICATIONS/TRANSPORTATION creases in travel, whether simply due to the "cabin DEMANDRELATIONSHIP fever" of being cooped up in the homeall day, or due Tworecent empirical studies illustrate someof the to the attempt to fulfill more complexpsychosocial aspects of the relationship between the demandfor needs. It maybe argued that this likelihood will be travel and the demandfor telecommunications that muchstronger in a work-at-home (especially full- have been discussed above. In the first, telecommuni- time work-at-home) situation than for local work cations maybe said to have stimulated travel, while in centers. In an admittedly short-term, small-sample the second, telecommunicationsclearly reduced trav- test conducted at SCAG,the hypothesis of signifi- el- at least in the short term. Together, they point up cant travel generation was not supported, even for the difficulty of predicting even the direction, let working at home. alone the magnitude, of the impact of telecommuni- From June to November1986, SCAGconducted a cations on travel demandin any specific instance. telecommuting pilot project for its employees Both studies were performed by the author while an (SCAG, 1986a). Seventeen people worked at home employeeof the Southern California Association of and one person workedat a satellite location, about Governments(SCAG), the metropolitan planning or- one full day every one-and-a-half weeks on average. ganization covering six counties in Southern Cali- Amongother things, the transportation impacts of fornia. telecommuting were evaluated. The major findings were as follows (SCAG,1988). 5.1 SCAGvideoconference In February of 1986, the regular monthly meeting (i) Telecommutingsaved an average of 46 miles per of SCAG’s Transportation and Communications occasion (that is, per person-day of remote Committee (TCC) was held as a two-way videocon- work). ference betweentwo California State University cam- (ii) Not even half (45%) of all telecommute occa- puses, instead of at the usual single location in SCAG sions generated travel during the usual commute offices. Details of the videoconferenceand its evalua- and work hours. tion are reported elsewhere (Mokhtarian, 1988; (iii) Aboutfive miles per occasion were generated. SCAG,1986b). The key findings were that: (i) (iv) Of that five miles, only about 0.2 miles were average trip length per person was 24%less for the attributed to newtrips that wouldnot have tak- videoconferencethan for a meeting at SCAG;but (ii) en place anyway, and some of that travel in- total vehicle-miles traveled were 29%higher for the volved walkingtrips. videoconference than for a typical TCCmeeting held (v) The remaining 4.8 miles generated per telecom- at SCAG.That was because (iii) attendance at the mute occasion were attributed to activities that videoconference was 64 %higher than average. would have taken place (at the same destina- The evaluation dealt with the question of whether tion) even if the conventional commutehad the higher-than-average attendance would have oc- been made. Assuming those activities would curred if the same meeting had been held in the con- have been linked to the work trip, the amount ventional fashion, or whether it could be attributed of new travel they represent depends on the ex- to the teleconference, and inferred that the latter was tent to whichthose activities fall on the route to by far the more likely explanation. Whetherdue to a work. An activity which is precisely on the way P. L. MOKHTaJ~IAN to workgenerates 100%new travel in a telecom- defy established categorizations. Thus, the muting situation, because that activity could homeviewing of commercial videocassettes is have taken place at no marginal cost if it had like viewinga TVmovie as far as its impact on been linked to the worktrip. Onthe other hand, movie theaters is concerned, but (somewhat) an activity which is essentially out of the way like a trip to the moviesas far as its transporta- generates no new travel, because virtually the tion impact is concerned. same amount of travel would have been genera- (v) In general, a synergistic generation effect ted to conduct that activity in conjunction with amongthe three forms of communication(per- the worktrip. son transportation, transportation of informa- (vi) Thus, there was a net savings of more than 41 tion objects, and telecommunications) can be miles per telecommuteoccasion. expected. That is, the morethat one or another (vii) As with the SCAGteleconference, even the extra form of communicationstakes place, the more miles that were generated entirely due to tele- that all forms of communicationare stimulat- commutingwere redistributed in time and space ed. There are numerousexamples of this. to less congestedparts of the transportation sys- (vi) Advances in communications technology will tem, permit us to do morethings and newthings, not just the sameold things in a different way.It is Again, these findings are far from definitive. A the inability to imagine those newthings that muchlarger pilot project now underway involving invariably confoundsattempts to predict the fu- employeesof the State of California (see JALAAsso- ture as a continuation of the past. Onthe other ciates, 1985; Kitamura, et al., 1990) will provide hand, the opposite extreme-predicting the de- more extensive data on the issue. But the SCAGre- mise of old technology in the face of the new- sults are plausible, and consistent with previous find- is equally problematic. ings (Nilles, 1988). A telecommuter who is truly (vii) The potential for relative substitution among workingeight hours a day won’t have a lot of time to the three modesis genuine; real-life examples makeextra trips. A newly available car maybe used abound. The preliminar3’ findings on telecom- by another household member,but those trips would muting, for example, are encouraging. Never- probably tend to be far shorter than the average com- theless, any travel savings that occur mayhave a mute and to take place in the off-peak. very localized impact, and it should be realized that the relative share of, say, transportation may decline even while its absolute level is 6. CONCLUSIONS rising. Throughout this discussion, a numberof points (viii) Finally, the most important impact of telecom- of interest to the transportation planning profession munications maynot be that it increases or de- have emerged. These points are summarizedbelow: creases the amountof travel that takes place, but that it permits a great deal moreflexibility There are strong commonalities between tele- (i) in whether, when, where, and how to travel. communications and transportation. These Telecommunicationsloosens the constraint of linkages are first and foremost conceptual, but havingto be at a certain place at a certain time. also physical, analytical, regulator~, and eco- Allowingpeople to take advantage of the excess nomic. capacity in the transportation system at off- (ii) The partnerships between the two fields can peak times and places promotes more efficient have mutually beneficial impacts on both sup- use of existing capacity and delays the need to ply and demand, as when transportation pro- construct expensive newinfrastructure. viders lease rights of wa.v to telecommunications providers, or when telecommunications Acknowledgements-Thispaper has benefited from the technology is used to maketraffic flow more thoughtful, detailed commentsof the referees and other smoothly, or when telecommunications reduces colleagues. the demandfor somekinds of travel. (iii) Despite the close ties betweenthe two fields, REFERENCES however,there will be situations for whichtele- communicationsproviders will have a different Airport Highlights(1989, April 10) First FAAMLS system agenda than transportation providers. This was commissioned.Weekly Newsletter of the Airport Opera- tors CouncilInternational, XXV(I 5), seen to be the case for car phones. It is also true Amato, M. (1989, May/June)Videocassettes grow with to a lesser degree for videoconferencing:the vi- businesstelevision. BusinessTV, 13. deoconference provider wants to increase the Beck,M., Meyer,M., Lewis, S., and Hager, M. (1988, De- use of transmission time and terminal equip- cember5) Smartcars, smartstreets. Newsweek,86-87. Beniger,J. R. (1986)The Control Revolution: Technological ment, oblivious to the additional travel created and EconomicOrigins of the InformationSociety. Har- because attending the meeting becomes easier vard UniversityPress, Cambridge,MA. for more people. Broadcasting(1989, July 3) Hollingsand Dingellmoving (iv) Technologywill create hybrid situations, that HDTV,40. Telecommunicationsand transportation 241 Brock, G. W. (198 I) The TelecommunicationsIndustry: The Washington Metro Authority. Communications Week, Dynamics of Market Structure. Harvard University 58. Press, Cambridge, MA. Kim,H. (1987, July 27) L. A. is at center of cellular war. Bush, G. M. (1988, October 31) Official fare approvedfor Los Angeles Business Journal, 1. lawyer’sshuttle. LosAngeles Daily Journal, Section II, 1. Kitamura,R. K., Nilles, J. M., Conroy,C., and Fleming,D. Clarkin, G. (1988, September12) Overnight delivery: Con- M. (1990) Telecommutingas a transportation planning solidation looms, fax threatens. AdweekSpecial Report: measure:Initial results of State of California Pilot Proj- Fall Preview1988, 75. ect. Transpn. Res. Rec. (Forthcoming). CommunicationsNews (1989, February) Videoconferencing Koenenn, C. (1989, February 20) The changing book for- goes to court during international tussle, 22, mats. Los Angeles Times, Part V, 1-2. De Sola Pool, I. (ed.) (1977) The Social Impact of the Tele- Kraemer, K. L. (1982, March) Telecommunications/trans- phone. MIT Press, Cambridge, MA. portation substitution and energy conservation (Part 1). Dow, J. (1989, April 17) Sony introduces two-way RDSS TelecommunicationsPolicy, 39-59. equipment. Shipping Digest, CXXIII, 4. Kraemer. K. L. and King, J, L. (1982, June) Telecommuni- European Conference of Ministers of Transport (ECMT) cations/transportation substitution and energy conser- (1983) Transport and Telecommunications. ECMT vation (Part 2). TelecommunicationsPolicy, 87-89. RoundTable 59, Paris, France. Lathey, C. (1975) TelecommunicationsSubstitutability for Feldman, J. M. (1986, October) Be prepared for the elec- Travel: An Energy Conservation Potential. United tronic dam to burst. Handling and Shipping Manage- States Department of Commerce,Office of Telecommu- ment, 54--57. nications. Washington, DC. Ferrell, J. (1984, May20) High-tech plan to streamline Mason, C. (1989. March6) LECsmust wait until at least transportation. San Francisco Examiner,Section D, 1. NewYear’s Day. Telephony, 8-9. Ford, L. R., Jr. and Fulkerson, D. R. (1962) Flowsin Net- Mason, C. (1989, March6) Rand study bolsters price caps. works. Princeton University Press, Princeton, NJ. Telephony, 9. The Futurist (1985, February) Dial-a-diagnosis, MemmottIII, E W. (I963, February) The substitutability Gherardi, G. (1989) The Los Angeles "Smart Streets" pro- communicationsfor transportation. Traffic Engineering ject. Presented at the 68th AnnualMeeting of the Trans- 33(5). portation Research Board. Washington, DC, January. Mokhtarian, P. L. (1988) An empirical evaluation of the 26, 1989. travel impacts of teleconferencing. Transportation Re- Giffin, W. C. (1978) Queueing: Basic Theory and Applica- search 22A, 283-289. tions. Grid Inc., Columbus,OH. Newman,P. W. G. and Kenworthy, J. g. (1988) The trans- Green, D. and Hansell, K. J. (1984, Nov-Dec.) Videocon- port-energy tradeoff: Fuel-efficient traffic versus fuel- ferencing. Business Horizons, 57-61. efficient cities. TransportationResearch 22A, 163-174. Harkncss, R. C. (1977) Technology Assessment of Telecom- Newman, P, W. G., Kenworthy, J. R., and Lyons, T. J. munications/Transportation Interactions. Stanford Re- (1988) Does free-flowing traffic save energy and lower search Institute, MenloPark, CA. emissions in cities? Search 19 (Sept./Nov. 1988), 267- Harlow, A. E (1936) OMWires and NewWaves: The Histo- 272. ry of the Telegraph, Telephone, and Wireless. D, Apple- NiUes, J. M., Carlson, E R. Jr., Gray P., and Hanneman, ton-Century Company,Inc., NY. G. J. (1976) The Telecommunications-Transportation Hawaii Department of Planning and Economic Develop- Tradeoff: Options for Tomorrow.John Wiley and Sons, ment (1984) Proceedings: Governor’s Conferenceon Vi- New York. deotex, Transportation, and Energy Conservation. De- Nilles, J. M. (1988) Traffic reduction by telecommuting: partment of Planning and Economic Development, status review and selected bibliography. Transportation State of Hawaii, Honolulu, HI. Research 22A, 301-317. JALAAssociates. (1983) Telecommunications and Energy: Obermann, R., Zobrak, M., Kumick, D., and Dartch, M. The Energy Conservation Implications for California of (1978) The Impact of Telecommunicationson Transpor- Telecommunications Substitutes for Transportation. tation DemandThrough the Year 2000. MITRECorpo- California Energy Commission, Sacramento, CA. ration, McLean,VA. JALAAssociates. (1985) Telecommuting: A Pilot Project Plane, D. A. (1986) Urbantransportation: Policy alterna- Plan. State of California Department of General Ser- tives. In S. Hanson (ed.), The Geography of Urban vices, Sacramento, CA. Transportation (ch. 16). The Guilford Press, NewYork. Jones, D. W., Jr. (1973) Must WeTravel: The Potential of Portway, P. (1988, October 10) Keynote speech to Telecon Communicationsas a Substitute for UrbanTravel. Re- VlllTeleconferencing Workshop, Anaheim, CA. port No. PB-227-185/6, Stanford University, Institute Ross, D. (1987, March) Warren Mathews: Puzzle-solver for CommunicationsResearch, Palo Alto, CA. emeritus. SCAGTelecommunity. Southern California Kahn, A. E. (1971) The Economicsof Regulation: Princi- Association of Governments, Los Angeles, CA. ples and Institutions. Volume2, Institutional Issues. Salomon,I. (1985) Telecommunicationsand travel: Substi- John Wiley and Sons, Inc., NewYork. tution or modified mobility? Journal of Transport Eco- Kanafani, A. and Parsons, R. (1989) Programon Advanced nomics and Policy 19,219-235. Technologyfor the High way- Vehicle/High way Naviga- Salomon,I. (1986) Telecommunicationsand travel relation- tion R & D. Presented at the Vehicle Navigation and ships: A review. TransportationResearch 20A, 223-238. Information Systems conference sponsored by IEEE, Salomon, I. and Koppelman, E (1988) A framework for Toronto, Canada, September 11-13. studying teleshopping versus store shopping. Transpor- Keppel, B. (1988, February 14) Reaching out: Small phone tation Research 22A, 247-256. firms quietly rewiring U.S. Los Angeles Times, Part IV, Sampson,R. J., Farris, M. T., and Schrock, D. L. (1985) 1. Domestic Transportation: Practice, Theory, and Policy, Khan, A. M. (1976) Travel vs. telecommunications: Current 5th ed. HoughtonMifflin Co., Boston. understanding (Part I) and modelling implication (Pan SCAG(1986, January) Implementation Plan: Telecommut- II). High Speed Ground Transportation Journal 10, ing Pilot Project. Southern California Association of 203-216, 217-245. Governments, Los Angeles, CA. Kieve, J. L. (1973)Electric Telegraph: A Social and Eco- SCAG(1986, February) Transportation and Communica- nomic History. David and Charles (Holdings) Ltd., tions Committee Teleconference Evaluation Report. Newton Abbot, England. Southern California Association of Governments, Los KUlette, K. (1987, October 26) ICC gets approval from Angeles, 1986. 242 E L. MordrrxgtxN SCAG(1988, August} Evaluation Report: Telecommuting TR News0989, July-August) Outsmarting the driver, 19- Pilot Project. Southern California Association of Gov- 20. ernments, Los Angeles, CA. Wolf, M. K. (press secretary to Los Angeles City Council- Thomas,E D. (1989, February) Merging fax into corporate man Zev Yaroslavsky). (April 18, 1989). Telephone networks. The Office, 15-18, 35. conversation.