Transportation 6 (1977) 57-70 57 © Elsevier Scientific Publishing Company, Amsterdam - Printed in the Netherlands

BENEFIT-COST ANALYSIS FOR LABOR INTENSIVE TRANSPORTATION SYSTEMS

MICHAEL E V E R E T T

Department of Economics, university of Southern Mississippi,

Hattiesburg, Mississippi 39401

A B S T R A C T

Labor-intensive systems such as bikeways and pedestr ianways suffer in transporta- t ion planning in part because t radi t ional benefi t -cost analysis focuses on narrow, private t ranspor ta t ion savings (e.g., reducing vehicle and t ime costs)•

Planners need benefi t-cost f rameworks which capture the communi ty -wide effects of such innovative t ransporta t ion systems - reduct ion in air pol lut ion, less congestion, and increases in exercise and ou tdoor recreation. This study discusses practical methods for planners to include such categories in their analyses and applies these methods to two case studies. The analysis yields benefi t -cost ratios which are much higher than those found in most public projects - suggesting negative returns to marginal automobi les in congested areas such as university campuses. The paper concludes wi th some suggested bikeway planning guidelines that emerge f rom expanded benefi t -cost analysis.

Introduction

The need for objective evaluation of labor-intensive transportation facilities derives from the growing role that bikeways and pedestrian paths are beginning to play in U.S. transportation systems - and from the subsequent interest in, controversy over, and funding for these facilities. The Federal Highway Administration ruled in 1973 that federal-aid highway monies - of up to $40 million - may be used for bicycle-pedestrian facilities, provided that:

• . . there is reasonable expec tancy that the trail will have sufficient use in relat ion to its cost to jus t i fy expendi tures of federal-aid and other public funds in its cons t ruc t ion and opera t ion [ 11.

To ~help funnel traffic into crowded central campus areas, many univer- sity administrators have restricted parking and opted for bicycle-pedestrian

58

systems. Other planners are making similar proposals for some central business districts and high-density recreation areas. Such radical change in transportation systems requires a more comprehensive benefit-cost frame- work to capture the broad social, economic, and environmental reper- cussions than is now usually employed.

Present benefit-cost frameworks fail to include such social-environ- mental benefits that accrue to bicycle transportation as reductions in con-, gestion, lower air pollution,, and increases in exercise and recreation. The AASHO Red Book, official guide for benefit-cost analysis of road projects, emphasizes narrow, private transportation savings, such as reductions in vehicle and time costs, but does not net out most of the external social and environmental costs of motor-vehicle transportation (Association of State Highway Officials, 1960). The Oregon Department of Highways, which pioneered benefit-cost analysis for roads in the 1930s, has become the first highway agency to apply the technique to bikeway projects, but they, too, use only the narrow categories of net vehicle and time Savings (Oregon, 1973).

This narrowness strongly biases transportation planning against energy and capital-saving technologies such as walking and bicycle commuting. This paper suggests some ways of overcoming, at least partially, these biases when planning bicycle, and, by inference, other labor intensive systems. As illustra- tions, these broader techniques are applied to two case studies. The paper concludes that benefit-cost frameworks which incorporate broad categories of nonmarket goods will more adequately capture the substantial benefits properly attributable to bicycle facilities and related systems, thus providing planners and administrators with a more discriminating tool of analysis.

Methodology

Benefit-cost analysis asks the question: Will this project make society as a whole better or worse off?. That is, will tl~e social benefits outweigh the social costs? In practice, the investigator compares the discounted present value of the yearly stream of benefits to the present discounted value of the yearly stream of costs.

Construction and maintenance costs present relatively minor problems. Several sources provide bike-facility costs (for example, see UCLA, 1972, Appendix A; Peat et al., 1973; and Oregon, 1973, p. 45), but lack of experience and inflation make prediction difficult. Theoretically, new machinery, basically construction machinery of the proper width, and materials which substitute capital for labor in construction, should reduce the costs of bikeways relative to the general price level and cost of road construction. General agreement is lacking on objective criteria for selecting

59

a discount rate (Prest and Turvey 1965, pp. 6 9 7 - 7 0 0 ) . Hence, some range around existing interest rates is usually employed.

Benefits and costs associated with changes in consumer surplus (the area between the demand curve and the price or cost curve) constitute the major problem and source of bias. The literature views a social benefit as an increase in "consumer surplus" (Mishan, 1970, Chapter 5). If bikeways drop the net costs of transportation for commuters, the amount of consumer surplus will increase. On the other hand, any increase i n price or loss of service the bikeway system causes - for example, converting parking spaces to bike lanes - reduces consumer surplus, for the driver at least, and should be considered a cost.

Investigators find it very difficult and expensive to establish the demand curve, and hence, obtain a true picture of consumer surplus and its changes (Prest and Turvey, 1965). Thus, analysts usually try to find market values for the goods and services under consideration [2]. For example, economists calculate the economic cost of diseases in terms of medical payments and foregone earnings rather than what an individual would pay to avoid the illness. The Army Corps of Engineers measures the loss of hunting and fishing resources of a water project in terms of the reduction in actual expenditures by sportsmen in the area. An extensive household survey indicated that the consumer surplus losses may be six to eight times as large as are conventionally derived (Environmental Research Group, 1974).

Failure to measure the loss in consumer surplus, particularly where large easily measured market benefits such as increased sales of power boats and fuel exist, biases benefit-cost analysis toward capital and energy inten- sive technology. In road projects, planners can estimate expected reductions in travel time and vehicle costs but find it difficult t o measure, and there- fore, tend to ignore the costs resulting from an increase in such nonmarke~. "bads" as noise, air pollution, and loss of access for nondrivers. , ,.~.

It will be difficult to rectify this deficiency in benefit-cost analysis for comparing bicycle and pedestrian systems to road projects. First, household surveys are expensive. S e c o n d , and probably more important , atti tudes toward cycling are changing rapidly and the results o f any study might be valid for only a short period.

Therefore, in this paper we will follow the traditio~a of using marke t measures, or shadow prices, to calculate net benefits, but we will utilize a wide range for each category. While this approach opens us to the criticism of inexactness and lack of rigor, we feel any bias we interject by .trying to measure these categories must be considerably less than the bias which exists by no t measuring them at all. Moreover, changes in the shadow prices for the nonmarket goods probably underestimate changes in consumer surplus. A discussion of each category - market and nonmarket - follows.

60

Benefit (Cost) Categories by Commuter Group

A bicycle facility or system will alter the modal choice of identifiable groups: Existing cyclists who use the bike facility (usually diverted from the road to a bikeway), drivers who switch to cycling because of the facility, pedestrians who begin biking, and individuals who now take additional trips by bicycle because of the facility. In turn, each commuter group using the bicycle facility generates a series of benefits (or costs) for himself and for society. Here we discuss a number of such categories, ranging from private to social benefits and costs, and give indications of how planners may quantify each.

A, REDUCTION OF TRANSPORTATION COSTS

Highway planners have utilized a number of benefit categories which are also appropriate to bikeways (American Association of State Highway Officials, 1960; Kuhn, 1962; and Winch, 1963):

(1) Reductions in vehicle costs including fixed operating, and parking costs. (2) Reductions in trip time costs. (3) Reduct ions in accident costs.

On short trips in congested areas bicycle transportation can produce substantial savings in terms of fuel (Hirst, 1974), time and parking costs (Everett, 1974a). But cyclists can enjoy much greater savings if they can give up ownership of a car (Sherman, 1967, makes a similar point). Even then, however, time costs for cycling over long distances, 10 miles or more, often swamp vehicle cost savings. Available data on these categories provide fairly accurate measures of partial changes in consumer surplus. (These and other data are available from the author.)

On the negative side, bikeway systems may encroach on motor vehicle traffic lanes or increase bicycle traffic at poorly designed intersections or on unimproved feeder routes exposing cyclists to accidents and air pollution and slowing down motorists. Mandatory use of bikeways may also slow down and otherwise inconvenience "eli te" cyclists. Planners should net out these increased costs or reductions in consumer surplus.

B INCREASED DESIRED BY-PRODUCTS

Beyond this narrow list of categories, we can add merit goods such as exercise, ou tdoor recreation, and relaxation, as low cost by-products o f bicycle transportation. Investigators find it quite difficult to measure real changes in consumer surplus for these categories, and hence, usually concen-

61

trate on reductions in monetary costs (e.g., Weisbrod, 1960); this tends to understate the benefits (Lave and Seskin, 1970, pp. 729-730; Environ- mental Research Group, 1974).

(1) Exercise: Scientific literature indicates that lack of exercise con- tributes to coronary heart disease (Cassell, 1971; Paffenbarger and Hale, 1975 ; National Heart and Lung Institute, 1971), the major killer in the U.S. (Heart Information Center, 1969). In a sedentary, mechanized, time-scarce society (Burenstam IAnder, 1970), the psychic and time costs of exercise are high, Bikeways which allow a commuter to obtain exercise as a by-product to transportation can cut these costs dramatically (Everett, forthcoming 1977). Shadow prices (McKean, 1968), such as the entrance fees to health spas and value of time spent there, provide estimates for the benefit accruing to those cyclists who value exercise.

(2) Outdoor Recreation: The demand for outdoor recreation has risen rapidly since World War II as the U.S. has become more urbanized and sedentary (Frank, 1962). Some writers have stressed the psychic need for relaxed recreation in wooded or at least attractive outdoor surroundings (e.g. see Clawson, 1959, pp. 27-33; Searles, 1960; and Stainbrook, 1973). Again, time and transportation costs are involved in driving to a park or other facility. Cycling home on an attractive bike route which passes through parks or quiet tree-lined residential streets can provide the outdoor recreation experience as a low cost by-product to transportation. Investigators have developed shadow prices using time, transportation, and entrance costs (Mack and Myers, 1965).

(3) Relaxation: Stresses in daily urban life often create "fight-or-flight" responses which if suppressed may lead to physiological disorders including tension headache, ulcers, and hypertension and cholesterol build-ups associated with atherosclerosis (Friedman and Rosenman, 1974). Bikeways interwoven into the urban transportation system help provide immediate and convenient physical outlets to these stresses and may reduce the mon:ey spent on cigarettes, alcohol and drugs.

c. REDUCTIONS IN NEGATIVE EXTERNALITIES

Most capital and energy-intensive transportation systems, particularly automobiles, impose extensive unintended costs on society through air and noise pollution, community disruption, and congestion, to mention a few. Recent environmental and social legislation has set standards and put restric- tions on transportation projects to reduce these costs (Council on Environ- mental Quality, 1972, p. 35).

But given the difficulties of measurement, most investigators have ignored these costs in making benefit-cost analyses. Such an approach obviously tends to over-value the net social benefits of capital and energy intensive transportation technologies.

62

(1) Congestion One automobile entering a stream of traffic slows down a number of

other automobiles in that stream and thereby imposes congestion costs on them. A British study, for example, shows that when a traffic stream in London is averaging less than 10 miles per hour an additional automobile imposes total congestion costs over $1.00 per vehicle-mile over all the other vehicles (Great Britain Ministry of Transportation, 1964, Appendix 2). Bikeways which divert some drivers from cars could produce substantial social savings. On the other hand, if the bikeway encroaches on traffic lanes and does not enjoy heavy usage, the net congestion costs will increase:

(2) Air Pollution Motor vehicles contribute about half of the U.S. air pollution by weight

(U.S. Environmental Protection Agency, 1972); more seriously they emit the pollutants down in the streets where pedestrians, inhabitants, (particularly of poorer neighborhoods), and drivers are directly exposed. Studies which have reviewed the literature present convincing evidence on serious long-run deleterious hea l th effects of roadside air pollution (Everett, 1974b). But at tempts to assign costs to automobile emissions have resulted in extremely low estimates and have n. ot been convincing (See Ahem, 1973, p. 176; Barrett and Waddell, 1973, pp. 5 9 - 6 1 ; and U.S. Senate, 1973, p. 69).

Diverting a driver to a bicycle reduces roadside air pollution. However, a bikeway constructed along a busy road may subject the vigorously exer- cising driver-turned-cyclist to serious deleterious, long-run health effects. These costs should be net ted out of any benefits.

(3) Other Environmental and Social Costs Investigators generally encounter even more difficulty in measuring

costs for noise pollution, water run off, communi ty disruption, and isolation of~nondrivers ' resulting from road building and motor vehicle transportation systems. But indirectly we can impute some of the reductions in transporta- tion costs accruing to bikeway systems.

If we assume that society has made a decision to reduce roadside and ambient air pollution, for example, and mus t reduce the number of motor vehicles 20 percent in a given urban area [3] , the social costs of removing these vehicles and making space for bicycle need not be net ted out of the benefits. In essence the social cost of limiting the motor vehicles is a sunk cost, and the question is how most efficiently to provide alternative non- polluting transportation.

63

D. ITEMS WHICH DO NOT Q U A L I F Y AS SOCIAL B E N E F I T S

The impact of bikeways on sales and local land values may provide very important information for local planners and policy makers. But technically, with cost-benefit analysis we are trying to assess the impact on the total society not on individual members. Sales and land values increase because transportation costs decrease. The decrease in transportation costs have already been accounted for in the above categories. Thus, to include in- creased sales and land values would constitute double counting (Mishan, Chapter 11). The same reasoning would exclude energy conservation since we already included reduction in fuel costs.

We have at tempted to quantify these benefits categories for two bike- way systems - Florida State University (FSU), a five mile system experi- encing very heavy use since 1972; and the University of Southern Mississippi (USM), a system proposed to mitigate the severe traffic congestion around the central campus. Table I presents the range of estimated benefits per mile

T A B L E I

Ranges of Savings per Mile for Traf f ic on Bike R o u t e s In and A r o u n d FSU by C o m m u t e r Type a (Cents /Mi le)

I II II l IV Benef i t Diver ted f rom Diver ted D i v e r t e d G e n e r a t e d b Categories cycling in road f rom driving f rom walking

Low High Low High Low High Low High

T r a n s p o r t a t i o n Acc iden t 1 10 Vehic le f ixed cost - 1 10 - 1 0 - 0.5 Opera t ing costs 1 5 - 2.5 - 1.5 0.5 Parking COSTS 3 10 - 4 0 1.5 T ime costs - 1 6 3 30 - 0 . 5

Ex te rna l Effec ts Road m a i n t e n a n c e 1 2 Conges t ion 1 12 Air po l lu t ion 1 2

- 6 - 0 . 5 0.5

By-Produc ts Exercise 2 6 0 0 1 Rec rea t i on 0 3 1 3 0 0 0.5

To ta l Savings 2 15 7 54 - 1 1 . 5 28 3

5 2.5 2.5 3

3 1.5

18.5

a A p p e n d i c e s showing a s sumpt ions and data sources may be ob t a ined f rom the au thor . i b G e n e r a t e d bike t r ips are ca lcula ted a t ~ the per mile value of o the r categories.

:64

for each commuter group. Note, that in spite of the downward biases shown in the table [4] , the inclusion of these broad, difficult to measure benefit categories raise the total per-mile benefits substantially above the narrow private transportation savings. The low-side benefit estimates increase several hundred percent while the high-side benefits increase 30 to 40 percent except for the category "Diverted from Walking".

Calculating Benefit-Cost Ratios

Benefit-cost ratios relate t he present value of the stream of yearly benefits t o the present value o f the stream of construction and yearly maintenance costs over the expected life of the project. Equation (1) illustrates one simplistic method for calculating the ~ present value o f net benefits for a bicycle facility or system.

N

B t = ~. t = l

Where:

B/ X Miles/

Mile Year

(1 ÷ i) t

B = total net benefits for each commuter group / t = the years of project life i = discount rate

(1)

The equation simply multiplies the benefits per mile for each commuter type (/) by the miles per year traveled by that commuter type [5], sums over commuter types and years (t), and discounts to the present. A table of present values will provide a discount multiplier for any given project life or interest rate.

For illustration, in our case studies we multiplied the low, middle and high net benefits per commuter group by the low, middle and high mileage estimates for each group (data available from author) to obtain a range of yearly streams of benefits. We assumed a project life of 15 years and a discount ra te of 6 percent. Therefore, we multiplied the range o f yearly benefits by 10, the discount coefficient for 6 percent over 15 years. Table I1 presents the range of present values of net benefits for FSU and USM across the top. We ranged the costs of both systems (construction and present value of maintenance) from $10,000 to $50,000 a mile for 5 miles. Total system costs are shown in parentheses on the lefthand side of Table II. The low side reflects extensive use of existing walks and roads with curb cuts or other minor improvements, university crews to build the System, and no charge for administrative~overhead such as planning and supervision. The high cost not

65

TABLE II

Benefit-Cost Ratios by Range of Estimate and Discount Rate (6% Discount Rate)

Present Value of Costs (Dollars given in parenthesis)

Present Value of Benefits (thousands of dollars, given in parenthesis)

FSU USM

Low Middle High Low Middle High (77) (1,839) (3,600) (37) (900) (1,800)

Low (50,000) 1.5 : 1 72:1 0.74:1 36:1 Middle (125,000) 14.5:1 7.2:1 High (200,000) 0.38 : 1 1 8 : 1 0 . 1 9 : 1 9 : 1

only reflects more comple te and higher cons t ruc t ion and main tenance costs bu t also the costs to pedestr ians and motor i s t s w h o lose space ( for travel and parking) to the b ikeway system.

Table II also presents possible combina t ions o f benef i t -cos t ratios for the range o f estimates. The FSU sys tem clearly shows a high posit ive pay o f f - 14.5:1 expec ted , a l though a negative rat io (0 .38:! . ) results f rom a dif- f e ren t combina t ion o f benef i ts and costs. Since the decision t o remove cars was a sunk cost, the $200 ,000 cost figure is unreal is t ical ly high. The high and

middle est imates (36:1 to 7 .2:1) o f the USM sys tem also gave substant ia l pay offs while again the low-side est imates were negative.

A more sophis t ica ted approach involves using c o m p u t e r s imulat ions t o generate con t inuous dis tr ibut ions o f benefi tocost rat ios f rom which prob- abilities o f any range o f pay off, including negative pay offs, can be es t imated (Hertz , 1964) [6 ] . F o r i l lustration, we ut i l ized a simple s imulat ion

TABLE III

Results of the Computer Simulation

Range of Costs (Dollars) Expected Probability of Benefit-Cost a Negative Pay-Off Ratios (Percentages)

Broad Narrow Broad Narrow

125,000" 5:1 3:1 0.2 1.1 200,000* 3.1 : 1 1.9:1 0.8 5.2 300,000* 2.1:1 1.3:1 3.6 22.2 300,000 (discounted at 10%) 1.6:1 1.1 : 1 7 . 9 4 4 . 0

* Discounted over 15 years at 6% except for last row which uses a 10% rate.

66

model to calculate equation (1) for the proposed USM system. The com- puter randomly selected values from the ranges of benefits for each category and from the ranges of miles for each commuter group to form 1,000 estimates of net yearly benefits which we then discounted over the life of the project (see Table III).

Table II! illustrates that including broad benefit categories makes a dramatic difference i n project evaluation. The narrow approach yields ratios only about 60 'percent as high as the broad approach, although ratios for both approaches are positive. The table also shows that the narrow benefit approach carries a much higher probability of a negative pay off. As costs rise, this risk increases much more rapidly for the narrow approach (to 44 percent) than for the broad approach (to 7.9 percent).

The much higher probability of failure projected by the narrow benefit approach would obviously reduce the attractiveness of a high-risk innovative transportation technology such as the proposed USM bikeway system. Moreover, the narrow benefit approach would cause much more severe biases where costs are higher, such as for bridges over freeways or expensive bike paths connecting up lightly traveled residential roads. In fact, our extremely conservative estimates of broad benefit categories undoubtedly introduces serious downward biases, and planners should seek to include more accurate measures as data become available (e.g., Wilson, 1973).

Planners can also h e l p overcome the biases against labor-intensive transportation systems by estimating the cost as well as the probability of failure. For example, o n e set ofal ternat ives facing the USM officials was to undertake a $5 million parking garage and street modification program or initially to spend several hundred thousand dollars to restrict automobiles from the central campus and build bicycle-pedestrian facilities. If the latter approach failed, officials could easily reverse i:t and then opt for the capital- intensive solution. But if the social costs outweighed the social benefits of a parking garage once constructed, the campus communi ty would have to live with its mistake and over the years suffer potentially" high losses.

Summary and Conclusions

Broadening the scope of benefit-cost analysis to include difficult-to- measure externalities and by-products can help reduce the present biases against labor-intensive transportation systems. The analysis has shown how planners can obtain useful information about these variables by: Construct- ing probability ranges for benefit-cost ratios rather than just point estimates: calculating the probability of failure as well as the expected pay, off; and examining the costs of failure.

We believe that the techniques and empirical evidence presented in this

67

paper support the following planning guidelines: (1) Well-used bikeways and facilities in congested areas should yield

high returns per dollar spent. But the very high value of land in such areas means that space devoted to little-used bikeways could lead to negative returns. Numerous college bicycle systems have demonstrated high returns. Similar success in other congested areas such as central business districts depend on a number of factors: Coordination of bike facilities with mass transit, car pooling, and peripheral parking; utilization of efficient compact bicycle parking areas; reducing conflicts with pedestrians; and restrictions on driving for environmental reasons.

(2) In less congested areas with more space, sufficient demand often does not exist for justifying a total system of bike trails. Concentrating on short trails which break dangerous barriers between sets of existing bikeways or safe residential streets may provide high payoffs. The benefits to such trails accrue not only to the mileage traveled on them but also to the increased cycling they stimulate at either end.

(3) In general, transportation planners should give more priority to flexible, low-cost, labor-intensive transportation systems. The very high expected benefit-cost ratios in our case studies suggest negative returns to capital-intensive transportation systems, at least in some congested areas such as college campuses. Planners should experiment where possible with labor-intensive systems, given their relatively low failure costs, before commiting themselves to capital-intensive ones, which are often irreversible and which have very high failure costs.

Acknowledgements

The author wishes to thank Victor Wolfe of the Oregon State Highway Division and Marie Birnbaum, Office of the Secretary U.S. DOT, for reading and distributing preliminary drafts of the paper for comments in their organizations.

The author also acknowledges the input of various student bicycle- pedestrian planning teams at Florida State University and the University of Southern Mississippi whose work contributed to this study.

Notes

1 states may use federal aid highway funds for bicycle/pedestrian trails (Federal High- way Administration, 1973: U.S. Congress 1973, Para 216, pp. 13, 70). States may construct these paths either in or out of the right-of-way as long as they divert cyclists and pedestrians from the federal aid road project.

68

2 Many planners also use a "cost-effective" approach which attempts to measure utility of the project to the community through attitude questionnaires (e.g., Braum and Roddin, forthcoming).

3 Baumol (1972) advocated standard setting over marginal cost-benefit analysis for difficult to measure environmental goods. The U.S. Environmental Protection Agency has set clean-air standards and has ordered communities such as those in the Wasl-dngton D.C. area to build extensive bike-routes systems to help meet these standards (U.S. Environmental Protection Agency, 1973). Wilson (1974, p. 48), for example, does a more complete study of the social cost of driving and finds that automobiles impose at least $1 to $2 per mile during rush hour traffic in the center of towns and cities.

5 Since the cost of sophisticated demand studies could exceed the capital cost of a bikeway system planners need to rely on simpler concepts such as the relative costs'of cycling versus driving (Everett, 1974a). We used crude traffic counts on the FSU bikeway system and interpolated to project the USM rates.

6 Although most planners will not have access to computer simulations, they can assume the ranges of benefit-cost ratios are normally distributed and utilize Z tables (found in any elementary statistics book) to calculate the probability of positive and negative pay-offs.

References

Ahern, William R., Jr. (1973). "Health Effects of Automotive Air Pollution." In H. D. Jacoby and J .D. Steinbruner, Clearing the Air: Federal Policy on Automot ive Emissions Control. Cambridge, Mass: Ballinger.

American Association of State Highway Officials (AASHO) (1960). Road User Benef i t Analysis for Highway Improvements. Washington, D.C.

Barrett, Larry B. and Waddell, Thomas E. (1973). Cost o f A ir Pollution Damage: A Status Report. Research Triangle Park, N.C. : Environmental Protection Agency.

Baumol , W. J. (1972). "On Taxation and the Control of Externalities," American Economic Review, 62: 307-322 .

Braun, Ronald and Roddin, Marc (forthcoming). The Benefits o f Separating Pedestrians and Vehicles. Washington, D.C.: Transportation Research Board.

Burenstam Linder, Staffan (1970). The Hurried LeisureClass. New York: Columbia University Press.

Cassel, John C. (ed). (1971). "Evans Country Cardiovascular and Cerebrovascular Epidemiologic Study," Archives o f Internal Medicine, 128 : 887-9 .

Clawson, Marion and Knetsch, Jack L. (1966). Economics o f Outdoor Recreation. Baltimore, Md.: Johns Hopkins Press.

Council on Environmental Quality (1972). Environmental Quality: The Third Annual Report. Washington, D.C. : U.S. Gov't. Printing Office.

Environmental Research Group (1974). Economic Survey o f Wildlife Recreation Resources in the Southeastern United States. Atlanta, Ga.: School of Business Administration, Georgia State University.

Everett, Michael (1974a). "Commuter Demand for Bicycle Transportation in the U.S," Traffic Quarterly, 28 :585 602.

Everett, Michael (1974b). "Roadside Air Pollution Hazards in Recreational Land Use Planning," Journal o f the American Insti tute o f Planning, 40: 83--9.

69

Everett, Michael: (forthcoming 1977). "The Economics of Exercise, Physical Fitness and Health." In Encylopedia of Physical Education Fitness and Sports Instruction, VoL II. Washington, D.C.: American Alliance for Health, Physical Education and Recreation.

Federal Highway Administration (1973). "Bicycle Routes Along or Crossing Federal-Aid Highways." Policy and Procedure Memorandum. (March 14). Washington, D.C.: U.S. Gov't Printing Office.

Frank, Lawrence K. (1962). "Outdoor Recreation in Relation to Physical and Mental Health." In ORRRC Study Report, No. 22, Trends in American Living and Outdoor Recreation. Washington, D.C.

Friedman, M. and Rosenman, Ray (1974). Type A Behavior and Your Heart. New York: Knopf.

Great Britain Ministry of Transportation. (1964). Road Pricing: The Economic and Technical Possibilities. (Report of a Panel set up by the Ministry of Transportation.) Her Majesty's Stationery Office: London.

Heart Information Center (1969). National Heart Institute. Washington; D.C. : U.S, Gov't. Printing Office.

Hertz, David B. (1964). "Risk Analysis in Capital Investment," Harvard Business Review (January-February) pp. 95-106.

Hirst, Eric (1974). Energy Use for Bicycling. Oak Ridge, Calif.: Oak Ridge National Laboratories.

Kuhn, T.E. (1962). Public Enterprise Economics and Transport Problems. Berkeley, Calif. : Univer. of Calif. Press.

Lave, L.B. and Seskin, E.P. (1970). "Air Pollution and Human Health,,' Seience, 169: 723-733.

Mack, Ruth P. and Myers, Sumner (1965). "Outdoor Recreation." In Dorfman (ed.), Measuring Benefits o f Government Investments. Washington, D.C.: Brookings In- stitute.

McKean, Roland N. (1968). "The Use of Shadow Prices." In S. B. Chase (ed.), Problems in Public Expenditure Analysis. Washington, D.C.: Brookings Institute.

Mishan, Ezra J. (1971), Economics for Social Decisions. New York: Praeger. National Heart and Lung Institute (1971). Arteriosclerosis. Washington, D.C.: National

Institutes of Health. Oregon State Highway Division (1973). Oregon Bikeways: Progress Report. Salem,

Oregon. Paffenbarger, Ralph S., Jr., and Hale, Wayne E. (1975). "Work Activity and Coronary

Heart Mortality," New England Journal of Medicine, 292: 545-550. Peat, Marwick, Mitchell and Co. (1973). A Comparison of Costs and Benefits o f Facilities

for Pedestrians. (Draft of Final Report for Federal Highway Administration) Washing- ton, D.C.

Prest, A.R. and Turvey, R. (1965). "Cost-Benefit Analysis: A Survey," Economic Journal, 75: 683-735.

Searles, Harold F., (1960). The Nonhuman Environment. New York: International Universities Press.

Sherman, Roger (1967). "A Private Ownership Bias in Transit Choice," American Economic Review 57:1211-17.

Stainbrook, Edward (1973). "Man's Psychic Needs of Nature," National Parks and Conservation Magazine. (September), pp. 22-3.

UCLA Institute of Transportation and Traffic Engineering (1972). Bikeway Planning Criteria and Guidelines. Sacramento, Calif.: Calif. Department of Public Works.

U.S. Congress (1973). Federal-Aid Highway Act of 1973. (Senate Report No. 93-355, July 27). Washington, D.C.: U.S. Gov't. Printing Office.

70

U.S. Environmental Protection Agency (1972). Compilation o f Air Pollution Emission Factors. Revised. Washington, D.C.: U.S. Gov't. Printing Office.

U.S. Environmental Protection Agency (1973). Environmental News. (November 26). Washington, D.C.

U.S. Senate Committee on Public Works. (1973). "The Social and Economic Costs and Benefits of Compliance with the Auto Emission Standards Established by the Clean Air Amendments of 1970." Washington, D.C. : U.S. Gov't. Printing Office.

Weisbrod, Bruton A. (1960). Economics o f Public Health: Measuring the Economic Impact o f Diseases. Philadelphia: Univer. of Pennsylvania Press.

Wilson, D. G. (1974). "Estimates of Pollution from U.S. Non-freight Highway Transporta- tion," International Journal of Environmental Studies, 6: 35-50.

Winch, David M. (1963), The Economics o f Highway Planning. Toronto: Univer. of Toronto Press.