Measuring Nonuse Value: A Comparison of Recent ...

Measuring Nonuse Value: A Comparison of Recent Contingent Valuation Studies

Thomas C. Brown

Rocky Mountain Forest and Range Experiment Station Fort Collins; Colorado

Abstract Thirty+ne contingent valuation studies published since 1980 that have estimated nonuse value were i d and compared. These studies estimated willingness to pay for m y different types of goods, used s a variety of methods, and produced a wide range of value estimates. Six different methods were used to isolate nonuse value. Lower estimates of nonuse willingness to pay resulted from mail surveys, in contrast to personal interviews; from using a contribution payment vehicle, in contrast to increases in prices or taxes; and from estimating nonuse value as the total willingness to pay of nonusers, in contrast to other methods of estimating nonuse value. Respondents of most studies indicated that nonuse value exceeds use value. Several studies found that nonuse value was higher for users than for nonusers of the good, suggesting that basing nonuse value solely on the responses of nonusers will underestimate nonuse value.

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Acknowledgment

This paper has benefitted from comments by Richard Bishop, John Loomis, Daniel McCollurn, and George Peterson.

Introduction Using contiigent valuation, economists have measured willingness to pay (WTP)for "nonuse" or "passive use" benefits (called "nonuse value" herein) for over 20 years. This. paper briefly summarizes and compares 3 1 such studies published in the United States since 1980. -1naddition to the text, a lengthy table in the Appendix

contains basic information about each study. This paper updates and expands on Fisher and Raucher's (1984) comparison of the fmt 6 studies (all published in the 1970s) to estimate nonuse value. Recently. much controversy has surrounded the measurement of nonuse value, centered on the validity of continge& valuation as used to measure the value of public goods, with particular emphasis on the "embedding' effect (Kahneman and Knetsch 1992). . It is not the purpose of this paper to address the validity question. This paper's more modest goal is to look across the variety of studies now available in order to (1) summarize the methods used, (2) report on the range of nonuse value estimates that have been obtained, and (3) compare estimates of use and nonuse value. This paper was motivated largely by two considerations. First, among the post-1980 studies that have

measured nonuse value, a wide range of methods has been used. This range of methods occurred partially because of the different types of goods thatwere studied. but also because of the lack of accepted ..

methodological guiaelines m the young field of contingent valuation. The ample recent activity in measuring nonuse value offered the oppommity to invkstigate the relationship of method to result, to perhaps indicate whether we should be more concerned about our methodological choices. Second, many of the studies measured both use and nonuse value, allowing a comparison of these two parts of total economic value. If studies consistently found similar ratios of use to nonuse value, we might have a basis for obtaining a rough estimate of nonuse value, and therefore total value, for the many studies that measured only use value. Although an attempt was made to include all recent contingent valuation studies that have estimated nonuse value, some studies have undoubtedly been missed. Apologies are due to the authors of any studies that were inadvertently overlooked. Hopefully those that are included adequately sample the population of such studies. The basic distinction between use value and nonuse value proposed by Randall and Stoll(1983) has been adopted here, which assigns option value to the use value category and assigns existence or intrinsic value plus bequest value to the nonuse value category. Because the studies s

A here differed in how they defmed

individual components of use value or of nonuse value, estimates for individual components were added in an

attempt to achieve comparabiliry across srudies. Thus. this summary compares aggregate estimates of use value and nonuse value. General Description of the Studies About half of the 31 studies were published iithe 1980s. with the remainder published in the 1990s.

Eleven of the 31 studies focused on wildlife and fish protection. Another third of the studies focused on water quantity or quality, and the remaining third dealt with wilderness preservation, forest quality, air quality. and o t h a types of goods (Table 1).

Mail surveys were used in 18 of the 31 studies, while seven studies used household interviews and four '

performed phonl.surV=ys (Table 2). ~ o u studies f distributed questiorimires to respondents onsite; with two of .

th&e asking k&dents

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to mail them back and the other two collecting the questionnaire. onsite. Among the

19 mail surveys used in the:18 studies, response rates ranged from 21 1to 84%. with a median of 391; this .

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is nearly identical to the median response rate among the 16 contingcntvai&ion studies listed by'~itche11and .

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Carson (1989; Table 12-3). The two highest mail re~~onse'rates were obtained in surveys that sampled only persons known tb be interested in the good: Loomis (1987) obtained a response rate of 84 % from users who were given-the questionnaire onsite and mailed it back, and Bishop and Boyle (1987) obtained a response rate of

81% from taxpayers who had ncently donated to the state's endangered species program. Only .one other of the .

mail surveys (Duffield 1992) sampled only users. The wide range of response rates for the general public samples (21% to 615%) may be due the nature of the good and to methodological choices such as repeat mailing

prccedure and length of survey. Response rates of the otha s w e y methods were inconsistently reported (see the Appendix). The two most common elicitation methods were the open-ended response, used in 12 of the 3 1 studies,

and the dichotomous choice response, used in 11 of the studies (Table 3). In addition, four of the dichotomous choice studies followed the yeslno response with an open-ended question. Five studies useduSed pajment cards, and only three, performed in the early 1980s. used a biddiig game. See Mitchell and,Carson (1989) for descriptions of each of the elicitation methods. About half of the studies used a contribution payment vehicle, whether it was to a "lmt fund" or a "special fundw(Table 4). The payment was sometimes called a "contribution" and elsewhere called a

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future period. Five studies focused on past use. For example. Boyle and Bishop (1987) asked respondents if they had ever made a trip with the intention to view bald eagles, Whitehead and Blomquist (1991) asked respondents if they had ever visited Clear Creek wetland, and Duffield et al. (1993) asked respondents if they *

had visited the subject river@) in the last three years. Four studies focused on future use. Three of these studies did not specify a specific future time period. For example, Stoll and Johnson (1984) asked respondents if they anticipated future visitation to the refuge. Walsh et al. (1985) focused on use "next year." The following two studies used combmations of past and future use: Olrm e! al. (1991) distinguished respondents who neither had fished for the subject species in the past five years nor expected to do so in the next five years,

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and Siiberman et al. (1992) distinguished respondents who had not and did not expect to use the beaches of .

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interest; With method 3, used by 5 of the 31 studies, respondents are asked to assume that they would not use the resource. For example, Boyle and Bishop (1987) told respondents that the bald eagle habitat at issue would be h remote parts of the state when viewing was not possible. ~uffieid(1992) told respondents to

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River Basin for water-based recreation.. ' With method 4, all (or nearly all) respondents arc assumed to be nonusers. Minimal use is reasonable if the resource is difficult to observe, such as the striped shiner (Boyle and Bishop 1987),'or if travel cost is significant and the sample is drawn from a general household population, as with Atlanta residents valuing waterfowl in the Great Plains and Rocky Moytains (Desvousge. et al. 1992). The surveys of seven of the, a

studies were considered here to allow for the assumption of nonuse. Note, however, that not all of the seven papers argued that all respondents were nonusers or that the estimated values were totally nohuse values. Nevertheless, their inclusion he& allows a comparison of the results of this method with the other methods. With method 5, used only by Dufield et al. (1993), total WTP is partitioned to use and nonuse portions based on statistical associations between WTP and responses to a series of behavior and attitude questions. Duffield et al. queried respondents about their past and expected use of the rivers in question and asked them to

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1992 and King et al. 1986). it might be argued that the method almost challenges respondents to demonstrate their environmental awareness by not lowering their previously stated WTP. (4) Assuming that the populatibn of potential respondents contains no persons who consider themselves to be current or potential personal users of the good is perhaps the simplest way to estimate nonuse value, but the assumption may be heroic for all but the most obscure goods. (5) Separating the use from the nonuse portion of the bid based on respondents' answers to a d e s of related questions avoids asking the respondent to make unrealistic assumptions or difficult cognitive distinctio&. However, the method requires a longer questionnaire and is subject to the common specification e&rs related to selecting the right questions to isolate the key motive variables.. (6) Asking dinkt normse value questions, l i e the apportionment approach, requires the respondent to make potentially difficult cognitive distinctions between use and nonuse value. ~ o n & Value e Estimates Fifty-one estimates of nonuse value; obtained from the 31 studies, are listed in the Appendix (in nominal doll&, along with the year of estimation). Adjusting for inflation (to 1990 dollars). these estimates varied from $1 to $184 per year per household, with a median of $23 (Table 7). A third of the estimates was obtained using method 1, another thud using method 2, and most of the remaining third was obtained using

methods 3 or 4. The range of estimates for each of these four methods is broad, suggesting that method (of isolating nonuse value) alone does not account for all variation in the estimates. Among the medians of the estimates obtained using the four more commonly used methods (Table 7), the mist notable f G d i is that the median for method 2 ($12) is considerably smaller than the median for the other three methods. The higher medians with methods 1 and 3; as opposed to method 2, may be attributable to the fact that the former two methods base nonuse value estimates on responses of both users and nonusers (more on this in a Iater section). The higher median with method 4, as opposed to method 2, may &t.

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inclusion of some use value in the bids of these "assumed" nonusers (i.e., fram.the inclusion of users or potential users among the respondents). The assumption of zero use value .may not apply to some of the seven method4 studies, for two reasons. F i t , two of the studies focused on the northern spotted owl (Hagen et al.

1991 and Rubii et al. 1991). While the respondents most likely realized that their chances of observing the

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secretive owl was remote, they may have considered owl preservation a vehicle for preserving old growth ecosystems that they did hope to visit for recreation. Second, three of the studies valued specially designated

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areas, either wilderness areas (Diamond et d. 1992) or national park lands (Schulze et al. 1983 and Hoehn 1991). While the areas were distant enough from the general population samples that use was unlikely for the

large majority of respondents, the areas were spdcial enough that the hope of visitation, and therefore option value, may have been substantial. These results suggest that cart should be used in applying method 4. Comparisons across studies are difficult bemuse of the many methodological differences between surveys. A larger sample of studies would be needed to allow an adequate statistical analysis of the effects of survey characteristics on measured values. However, some interesting patterns appear by examining chakcteristics of the studies that produced the highest and lowest nonuse value estimates. We will consider five characteristics for the bottom and top quartilcs among the 31 studies listed in the Appendix. The 14 estimates and their methodological characteristics are listed in Table 8. Nature of the good. Both lists include a variety of types of goods covering a range of uniqueness. W

e there arc no obvious differences between Lhe goods in the bottom quartile and those in the top quartile,

the t o e e probably contains more high visibility goods (e.g., Grand Canyon. national parks, spotted owls) than the bottomquartile. Other evidence suggests that the nature of the good does matter. For exampIe,

Bishop and Boyle (1987) found that reported n o n w value was several times higher for bald eagles than for

striped shiners. Survey administration. Six of the seven lowest estimates were obtained in mail surveys, while only

two of the seven highest estimates were so obtained. All five of the remaining high estimates were household

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Comparing Users' and Nonusers' Nonuse Values Six of the 31 studies allow comparisons of users' and nonusers' nonuse values (Table 10). Three of the studies used method 1 (direct apportionment) with user and nonuser subsamples. Two studies used method 3 (assumed z r o use) with user and nonuser subsamples. The other study obtained users' nonuse WTP using method 6 (asking a specific nonuse value question) and nonusers' nonuse WTP using method 2 (total WTP of the n o n k subsample). In-threeof the studies, users wen distinguished from nonusers based on past behavior,

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whiie in the other three studies the distinction was made based on expected future behavior. It is not clear to ' .

what extent past nonusers might be future users, or to what extent expected future nonusers were past users. . ',, ., ...

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The 7 ratibi 'of users' to nonusersinonuse values range from 1.4 to 2.6 (Table 10). suggesting that past

future use tends to enhaice nonu& WTP. Note that the fmdigs of two other studies (Loomis

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- -

1987a,b and Stoll and Johnson 1985) tend to substantiate this finding. Howber, in each study the users' and

nonusers' estimat& of non& value were obtained using different ^survey administration procedures, so the

.

._-T_.

:

.

.. .. r

,

..

.

mi&&'& Blom@kt (199l)'Ff&ide &ditional.&idenk of the effect.of-'usehn

IIO~UX value.

Past nonusers of Clear Creek wetland were separated into two subsamples depending on whether they had "information' about wetlands. This 'information' was either onsite use of other Kentucky wetlands or offsite sources such as television or conservation literature. The ratio of mean WTP of the informed subsample to

WTP of the unhformed subsample is 3.14. One explanation of the results of the six studies listed in Table 10 is that past or expected future use is associated with information about the good, and that information, as Whitehead and Blomquist (1991) suggest, enhances nonuse value. Obviously, past use provides information about the good. Furthennore, respondents' '

plans for future use may have resulted from information gathered about the good. If nonuse WTP. is sensitive to infdnnation about the good, we would expect users' nonuse WTP to exceed nonusers: WTP to the extent that users have more information than nonusers. Of course, the converse of this explanation is also feasible

- that those whose nonuse value is higher

for a given resource tend to accumulate more information about the resource than those with lower nonuse

PLI I@ sdeqlad uatp ' a m a q s! y q 31 ' ~ L Mpnl3e ~I!M op 01 apq1 aheq l e g sapru!ue ah!laJje pan38

no paseq slnanodmm a n p oi d m natp a ~ m natp p ' d m @lo1qatp &sa sdeq~ad's! l e u *pavqamind ~ a ~ p f l aq m d m ptp sqm OMJ U

aheq datp =no 'auapnodsa

L I O 01 ~ ~mapnodsar

-bar

1 poqmm

mp s! 01 a I q L y'papxIar s o p I-poplam ah!l!sod atp jo u o ~ ~ d a~q!ssod x a laploare ' ~ a ~ a m o ~

-1uapuodsar t p a m a g q s a &LM auo Apo sar!nbaJ I! asnmaq an@Aasn ~ u n malqnop 01 slnapnodsar molp IOU saop a n p asnnon %uploqjo 1 potpaH ,

'(01 a1qL y

pals!^

sa!prus q s atp jo a a q dq pasn) I p o p m no paseq so!m atp 01 d~dde)on plnm sxasnnon

ueq srasn jo sp!q asnnou ~aq%!qatp jo n o p m ~ d x aSuyunm alqnop atp 'sa!prus E-potpam atp y aqgun 'p!q a q !TI papn13y aq IOU ppoqs anprl asn m p w s Ap!3!ldxa aq, aaqm 'Aprus (2661) 'p la m a q p g atp n! m q d1aq1

IOU

p p u o y n b =@A m u o n

maas I! mq 'alq!mqd maas anpA m 8 q m m

alqnoa -0u.na3s asn 0.n~ atp jo w w ! p atp %upon%!dp!3!ldxa aram auapnodsar a q ' m p asn ~ @nmad amos papnlaq ol~mra35asn am~yaraz paamsse atp 01 sasuodsu j! o m ) so-

-das

& ~ ~ r uns s atp jo 3

OM;

ma .(am anuq prnalod pue am anuy

o w iapun d m n a g a m p s a oa paqse a n nnapuodsar a.139~'(01 a1qu a!

-

'dq pasn) E powm no paseq s o w m p os@p ~ n ma n p ~ s q m m alqnoa

,

. a n p asn 1mm alqnop 01 lClpn.uoddo atp peq sxasn army p a l d x a 's! leu

~sasnodsa.~ 1!3Q y anpA asn m o s Sypnl3y l s q ~ % pamm A p y 3 3 d s

JO

may papnlzxd IOU arafi auapnodsar

a g ' s a w atp 'a~otsalolammv ssed m m u a due 01 pappe q ppom .%ymoq A ~ d e s ,~ oa ju a d e d atp m p

a q asn 01 alqe aq I~!M aldoad a o m l e g 8 q m o q dldqs,

JOJ

d m jo almn!lsa almdas e appard 01 'uo!lsanb

anpA asn e %upamsueJaye 'srasn army w b a r q q m 'pasn btp spoqram a q uarr!% aIq!sneld s! rCl!pq!ssod . q 'paapg . a n p asnuon JO samqsa ,srasn y papnl-

lev anpA asnuou ,wasnuon aruy 01 'srasn ammJ 30 so!m

Syaq a n p asn ~ ol alqmnqgn aram punoj datp

a~n!sodatp mp papnpum L a u . u o ~ o i s aqxaq ~

loj d l & lnoqe m p 1!aq no paseq no!mldxa lnaJaJJ!p a!nb e lago 'Ja~amoq'(~661)'@ la m a q p g epalnseaw aq m anph u! mualajpp q:,ns 1eq pm 'poo8 atp t p ! ~d1!.re!~u1~23~ I ! M paleposse s! aualajyp aql lev 'Jajyp s a n p asnuou s,a~doad~etps! uo!lsa53ns aq1 '(uo!ieuuoju! a q n b ~ e01 auo s~dmoldanpA 10 a n p uapua8ua uo!~euuoju!Jaqlaqm) ase:, laql!a u~ .sanleA

respondents (both users and nonusers) would tend to repon the same percentages for allocating their total WTP, and the higher total WTP of users would result in greater nonuser WTP for users than nonusers. However, the evidence does not support this explanation. The three method-1 studies that allowed computation of ratios of nonuse value to use value for both user and nonuser subsamples (Table 11) all found quite different ratios across the two subsamples. [Note that "nonusers" can provide estimates of use value as long as nonuse is not defined

as "no fume use expected."] Two of the studies (Duffield et al. 1993 and Walsh et al. 1985) found considerably lower ratios for users than for nonusers (i.e., users allocated more of their total WTP to use motives than did nonusers). In spite of the lower ratios for users than nonusers, the users' significantly greater total WTP'caused their nonuse value to exceed that of nonusers. The third study (Clonts and Malone 1990)

repbried a higher ratio of nonuse to use value for users than nonusers (both the use value and nonuse value of users e x d e d those of nonusers, but the diffmnce in nonuse values was by far the greatest). Perfiaps the difference between Clonts and Malone's finding and that of the other two studies is partially explained by the fact that in the former &dy a respondent was considered a user if a household member (not necessarily the e k d e n t ) &f-&-~ie

6f thi= 15 riv& in the past th;se yeari;while in the latter studies use was dependent

on the respondents' behavior.

The hypothesis that use is pmeded by and enhanoes information, and that information increases nonuse value, is a parsimonious but tentative explanation of the ratios listed in Table 10. If this hypothesis is accepted, method 2 must be rejected as a way to partition total value. If comparisons based on method 2 an removed from Table 9, all but thrke of the remaining 22 ratios of nonuse value to use value exceed 1. These 22 ratios range from 0.6 to over 10, with a median of 2.56. Conclusions

This comparison of 31 studies suggests that basing nonuse value solely on the r e s p o k of nonusers or uninformed respondents will underestimate nonuse value. Given the opportunity, respondents almost always

report that their nonuse WIT exceeds their WTP for personal use. However, while the consistency of this finding across many studies increases its credibility, circumspection is advisable because nearly all of the estimates are based either on self-reported allocations of total WTP or on respondents' estimates of WTP given

I

a hypothetical zero-use scenario. Additional studies of the type performed by Duffield et al. (1993). which do

not directly rely on respondent breakdowns of total WTP, are needed. The comparison .. of studies suggests that lower estimates are obtained (1) using a mail survey in contrast

to personal interviews, (2) using an annual instead of a monthly payment period, and (3) using a contribution payment vehicle rather than increases in taxes andlor prices. Tests of these hypotheses are warranted if contingent valuation of nonuse value is to be used for policy decisions. The hodgepodge of methods used by the contingent valuation studies summarized herein made comparison of the studies difficult. The assortment of methods is reasonable given the immature state of the .

.

field of contingent valuation,and the lack of generally accepted guidelines. Nonetheless, the field would benefit

from a series of systematic studies to test hypotheses such as those listed above, followed by an effort to standardize contingent valuation methodology.

Literature Cited

I

1 .

Boyle, Kevin J., and Richard C. Bishop. 1987. Valuing wildlife in benefit-cost analysis: a case study involving endangered species. Water Resources Research 23(5):943-950.

rooks shire, David S.. Larry S. Eubanks, and Alan Randill.

1983. Estimating option prices and existence values for wildlife resources. Land Economics 59(1):1-14.

Cloxits, Howard A., and Joy W. Malone. 1990. Presewation aaitudes and consumer surplus in fTee-flowing riyers. kc Social Science and Natural Rerource Recreation Management, Joanne Vining, editor, pages 301-3 17. Westview Press, Boulder, CO. Cronin, Francis J. 1982. Valuing nonmarket goods through contingent markets. Pacific Northwest Laboratory, PNL4255,. Richland. WA. Desvousges, William H., V. Kerry Smith, and Matthew P. McGivney. 1983. Contingent valuation design and results: option and existence values. In: A Comparison of Alternative Approaches for Estimating Recreation and Rebed BeneJis of Water Quality Improvements. U.S. Environmental Protection Agency, Economic Analysis Division, Washington, D.C. Desvousges, William H., F. Reed Johnson. Richard W. Dunford, Kevin J. Boyle, S m P . Hudson, and K. Nicole Wilson. 1992. Measuring natural resource damages with contingent valuation: tests of validity and reliability. In: Comingent Valuarion:A Critical Assessment, from the symposium, April 2-3, Washington, D.C. Cambridge Economics, Inc., Cambridge, MA. Diamond, Peter A., Jerry A. Hausman, Gregory K. Leonard, and Mike A. Denning. 1992. Does contingent valuation measure preferences? Experimental evidence. kk Contingent Valuation: A Crin'cnlAssessment, from the symposium. April 2-3, Washington, D.C. Cambridge Economics, Inc., Cambridge, MA.

-

Duffield, John. 1992. An econorhic analysis of wolf recovery in Yellowstone: park visitor attitudes and values. In: Wolvesfor the United States?. A report to the U.S. Congress, volume 4: research and analysis, John D. Varley and Wayne G. Brewster, editors, pages 2-31 to 2-87. National Park Service, YeIlowstone National Park, WY.

Duffield, John, Thomas C. Bmwn, and Stewart D. Allen, 1993. ~conomikvalue of recrcation and

.

preservation benefits of instream flow in Montana. Research Paper in prtss, Rocky Mountain Fo&t and Range Experiment Station, U.S. Forest Service, Fort Collins, CO. Fisher..Am, and Robert Raucher. 1984, Intrinsic benefits of improved water quality: conceptual and empirical perspectives. In: Advances in Applied Micrb-economics, Volume 3. V. Kerry Smith and Ann Dryden, editon, pages 37-66. JAI Press. Gilbert, A., R. Glass, and T. More. 1992. Valuation of Eastern wilderness: extramarket meas&,of public support. In: ;lhe Economic Value of WIdemess: Proceedings of the Conference, Jackson, WY, May 8-11, 1991, pages 57-70. General Technical Report SE-78, Southeastern Forest Experiment Station, U.S. Forest Service, Asheville, NC. . "'

I

Greenley, Douglas A., Richard G. Walsh, and Robert A. Young. 1981. op;ion value: empirical evidence froma case study of recreation and water quality. Quarterly Journal of Economics 963657472.

Haefele, Michelle, Randall A. Kramer, and Thomas Holmes. 1992. Estimating the total value of forest quality in high-elevation spruce-fir forests. In: me Economic Value of Wilderness: Proceedings of rhe Conference, Jackson, WY. May 8- 11, 1991, pages 91-96. General Technical Repon SE-78. Southeastern Forest Experiment Station. U.S. Forest Service, Asheville, NC.

-

Hageman, Ronda. 1985. Valuing marine mammal populations: benefit valuations in a multi-species &system. Administrative Repon No. U-85-22, National Marine Fisheries Service, Southwest Fisheries Center, La Jolla, California. Hagen, Daniel A., James W. Vincent, and Patrick G. Welle. 199.1. The benefits of preserving old-growth forests and the northern spotted owl. Forthcoming. . . Hoehn, John P. 1991. Valuing the multidimensional impacts of environmental policy: theory and methods. American Journal of Agriculmral Economicr 73(2):289-299.

Kahneman, Daniel, and Jack L. Knetsch. 1992. Valuing public goods: the purchase of moral satisfaction. Journal of Environmental Economics and Ma~gement2257-70.

King, David A., Deborah J. Bugarsly. and William W. Shaw. 1986. Contingent valuation: an application to wildlife. School of Renewable Natural Resources, University of h n a , Tucson. Loomis, John. 1987a. An econo&c evaluation of public uust resources of Mono Lake. Ecology Repon 30, College of Agricultural and Environmental Sciences Public Services Research and Dissemination Program, University of California, Davis. .

..

,

.

.

.

. ..

Lwmis, J&UL 1987b. ~ a l k c i n public b trust nkurces i f ~ ~ n o L .a and k~-e Lcr Angela'...water . right: . .-an. economic *roach.-, Water Resckrcei R&&&~ 23: 1449-1456. ~~

.

,

. . . .,

.

.

~

. .

.

Mitchell, Roben C., and Richard T. Carson; 1981. ' ~ experiment n in determining wdlingness to pay for national water quality improvements. P r e l i m Draft of a report to the U.S. Environmental Protection . Agency. Resources for the Future, Inc., Washington, D.C. '

Mitchell, Roben C., and Richard T. Carson. 1989. Using surveys to value public goods: the contingent valuation method. Resources for the Future, Inc., Washington, D.C. Olsen, Darryll. Jack Richards, and R. Douglas Scott. 1991. Existence and sjnrt values for doubling the size of Columbia River Basin salmon and steelhead runs. Riven 2(1):44-56. Rahmatian, Moneza. 1987. Component value analysis: air quality in the Grand Canyon National Park.. J o u d of Environmerual M a n a g e m 24:2 17-223. Randall, Alan, John P. Hoehn, and George S. Tolley. 1981. The structure of hntingent markets:' some results of a recent experiment. Presented at the AEA and AERE joint meeting, Washington, D.C. Randall, Nan, and John R. Stoll. 1983. Existence value in a total valuation framework. In: Managing air quality and scenic resources at national parks and wilderness areas, Robert D. Rowe and Lauahe G. ., Chestnut, editors, pages 265-274. Westview Press, Boulder, CO. Rubin, Jonathan, Gloria Helfand, and John Loomis. 1991. A benefitcost analysis of the northern spotted owl. Journal of Forestry 89(12):25-30.

Sanders, Larry D., Richard G. Walsh, and John B. Loomis. 1990. Toward empirical estimation of the total value of protecting rivers. WaferResources Research 26(7): 1345-1357. Schulze. William D., David S. Brookshire, Eric G. Walther, et al. 1983. The economic benefits of preserving visibility in the national parklands of the Southwest; Natural Resources Joumaf 23 :149-173. Silberman, Jonathan, Daniel A. Gerlowski, and Nancy A. Williams. 1992. Estimating existence value for users and nonusers of New Jersey beaches. Land Econornicr 68(2):225-236. ~tev&, ~ h 6 k H., s Jaime Echeverria, Ronald J. Glass, Tim Hag&, and Thomas A. More. 1991. ~ c a s & n ~ the existence value of wildlife: what do CVM estimates really show? Land Economics67(4):390400. Stoll, John R., and Lee Ann Johnson. 1985. Concepts of value, nonmarket valuation, and the case of the whooping crane. Transactions of North American Wildlife and Natural Resource Conference 49:382-393. .* Sutherland, Ronald J., and Richard G. ~ a l s h ; 1985. ~ f f e cof t distince on the preservation value of water quality. Land Economics 61(3):28 1-291. "

.,

.

..

::..

Whit=hcad, John c., and GI- C. Blnnquist: 1991. A link . between . . behavior, information, and existence . . . .. . . . ,.. . . . . . . - value. Leisure Sciences 13:97-109. : ,

-

?

Whitehead, John C., and pier A. &thuia 1992.~'~cdn~lhic benefits of improved water quality: a case study of North Carolina's Tar-Parnlico River. Riven 3: 170-178. Walsh, Richard G., DougIas A. ~ r e e n l e ~ , ' ~ o bA. e rYoung, t John R. McKean, and Anthony A. Prato. 1978. Option values, prt5servation values and recreational benefits of improved water quality: a case study of the South Platte River Basin, Colorado. EPAd00/5-78-001, Socioeconomic Environmental Studies Series, . . Office of Resmrch and Development, U.S. Environmental Protection Agency, Research Triangle Park, ... . . . . . .. . . . . . . . . . . . . . . . . . NC. .-. . . . . . . ..-.,-. .. . .. . . . . . . ..... . .>

.....

Walsh, Richard G., John B. Loomis, and r;i'chard A. Gillman. demands for wilderness. Land Ecdnomics 60(1): 14-29.

.

.

. .

, .

.

.

~

1984. Valuing option. existence. and bequest

Walsh, Richard G., R. Derek Bjonback, Richard A. Aiken, &d Donald H. Rosenthal. 1990. Estimating the . . public benefits of protecting forest quality. Journal of Environmental Management 30:175-189. :

1 -

I

*

w.I.0.L UOy?lOlsar rpaa u o ! ~ ~ ~ a spau~e dp a ~ r(l!@nb ,sarod

Z

no!le~asardssanrapp~

E

h!@nb J!v

E

l a ~ aaye1 l JO MOD J ~ E M

P

r(l!@nbJaEM

9

uo!13alo~d~SIJ pue ~J!IPI!M

II

sa!pn~sJO JaqurnN

adA~,poo9

so661 pue so861 aqi jo sa!pn)g anle,\ amuoN u! spoo3 jo a d L ~

'T alclYI.

Table 3. Elicitation Method

Number of Studies'

Method Openended

12

Dichotomous choice

11"

Payment card

5

Bidding game

3

Other

33

TOTAL

34'

'Studies using the method with a separate sample. 2Four of these studies asked an openended question afier the dichotomous choice question. These studies are not also listed as openended in this table. . . - 3Hoehn%(1991) and Desvousges et al. (1983) used multiple elicitation methods. - dlbnts and Malone (1990) did not report elicitation method. 'Some of the 31 studies used different methods with different samples.

---- - -. Table 4. Payment Vehicle -

Vehicle

.

Number of Studies

Contribution to a special fund

15

Increases in taxes andlor prices

6

Special tax

4

Utility bill

4

Payment to a special program

1

Not reported

2

TOTAL

31'

'In addition to these vehicles, some of the studies also used other vehicles for comparison.

uo!lsanb anpA asn aleredas e no paseq (IU suogsanb so!~epaq pue a m p or sasuodsar no paseq pauopodde d m en

~'ouo!~sanb a n p asnnou aimdas e no paseq m suopsnb ~ o ~ e q pue aqapwp paseq pauo!uoddr? &LM

01 samodsax no

01 pamnsse an

'

slasnnou aq oqm 'slnapuodsai 1@jo

9 S

P

asn

olaz anmsse 01 payse ase slnap~&l uaqm d~ snup srasn p!~na)od 10pJO

asn araz amnsse 01 paqse an nnapuodsa~a a q &LM ~

a l d m q n s Jasnuou d m

€

a~dmsqnsasn nu on jo

j o d m snuy a~duresqns~ a s jo n

luapuodsa~Lq pano!uod& d m

.--

Z

1uapuodsai Aq pauo!uodde a n p a~s n n o ~

a n p asn

s n @ A Xfl Pm asnnoN -3~losl Jo SPoqtaW 30 -S

I Po'PM -9 a1W.L

.

Table 7. Estimates of Annual Nonuse Value Method'

Number of Studies

Number of Estimates

1

12

2

Nonuse Value'

Low

High

Median3

17

$5

$184

$3 1

11

16

1

155

12

3

5

7

17

139

59

4

7

7

7

155

63

5

1

2

8

12

10

6

1

2

18

23

21

374

51

$1

$184

$23

'~ll

'Willingness to pay per household per year in 1990 dollars. The one-time payments are included here as annual payments. Where a range is listed in the Appendix table, the midpoint is used here. Wethod of isolating nonuse value. See Table 6. 'Given an ev& number of estimates, the median is the midpolnt of the median pair. 4Some of the 31 studies used more than one method. ..

Table 8. Characteristics of Studies Producing the Highest and Lowest Estimates of Nonuse Value' WTPZ

Study

Payment period

Payment vehicle

Method3

mail

annual

contribution

2

Administration

Good

Bottom quartile $1

Stoll & Johnson (1985)

crane habitat at

Aransas 4

Duffield et al. (1993)

flow in 1-5 MT rivers

mail

annual

contribution

2

5

Gilbert et al. (1992)

Eastern wilderness

mail

annual

contribution

1

6

Whitehead & Blom.(1991)

wetland protection in mail

annual

contribution

2

7

Boyle & Bishop (1987)

s h i e r habitat in WI. mail

annual

contribution

4

10

Brookshire et al. (1983)

sheep habitat in WY

mail

annual

contribution

2

11

Silberman et al. (1992)

beach restoration in

interview

one-time

contribution

2

KY

NJ Top quartile 86

Hagen et al. (1991)

spotted owl habitat in CA

mail

annual

taxeslprices

4

92

Desvousges et al. (1983)

Monongahela R. quality

interview

annual

taxeslprices

3

127

I Hoehn

(1991)

139

Greenley et al. (1981)

155

Schulze et al. (1983)

155 184

I Grand Canyon air I interview Wity Platte Basin water quality parklands visibility

monthly

I' program

4

>

interview

annual

tax

3

interview

monthly

utility bill

4

annual

taxeslprices

2

monthly

utility bill

1

Mitchell & Carson

river water quality in interview

(1981)

U.S.

Loomis (1987a, b)

Mono Lake levellquality

mail

'To avoid doublecounting, no more than one estimate of nonuse value from a given snidy was included here., 2WTp per household per year in 1990 dollars. Method of isolating nonuse value. See Table 6.

Table 9. Ratio of Nonuse Value to Use Value'

Method2 NonuseIUse

Number of Studies

Number of Estimates

Low

High

Median4

111

12

17

0.97

10.74

2.56

U2

9

12

0.11

3.89

0.85

313

3

0.60

7.57

3.17

515

1 2 23

3 2

3.17

7.32

5.25

3

0.85

2.97

1.46

10.74 0.11 All 34 'Where a range of WTP is listed in the Appendix table, the midpoint was used here.

1.92

316

~atio~

.

2Methods of isolating nonuse and use values; see Table 6. 'All ratios are listed in the Appendix. 'Given an even number of estimates, the median is the midpoint of the median pair.

-

-npuad& atp tq palsy a n so!m

. a n p asn 01 a n p asnuou jo o m I

9S'Z

ZL'T

E ised

P6' 1

ZL'Z

mrC 1xan

90'1

L9'E

srasnnoN

-n b

10m

-A

E i=d

(58616 '@ la F@A (~661)'@ la P P W ~ (0661)a n o p pne ~ won

:uo ~ a = a~ * nJO n o ~ ~ ~ a a

AP~S

srasnuoN p w msn JOJ anp,i asn w an^^ asnuoN JO so!tw I p o q t a ~-11 aIqBj

-

, , ,

' m d ixau a x n o s 1 a v asn lou plnom Latp m p q r ~ ~ alam a s ~ a s n n o.m ~ A 1 x 3 asn ~ jo upma aram slasn .an@A asn e papyo~do q nuapuodsar ~ Am alaM S a m parap!sucM osw *srasnuoujo a n p asnuou 01 sIasn jo a n p asnuou jo o m -9a l q q aas t a n p asnuon 2up1oy JO p o p ~ i y .srel~opp o n .tr! ~ e a Alad p~oqasnoqlad I 'xpuaddy atp u! pay1 are saiempsa a n p 1~

I

E ~sed

E

="lnJ

219

="lnJ

51

amnJ

OZ

01

C p l lxau

95

ZZ

m C r E ised

OS$

8Z$

28'1

sea6 i s 1

99

ZP

LC-I

01

L

ZP'I

L9

ZP

09'1

6

E9' I

L0.Z

SS'Z

~O!letI

slasnuo~ an@^

,

-A

:uo pa-a 3asn jo uo!l!ugaa

slasn

asnuo~

I

(5861) '@

219

FFM

srasnuou ired uasn lsed

(2661) '@ la m a q l ! S (1861) '@ P hlnaar9 (€661)'@ 13 P P w n a (~861) 'le la = s s n o ~ = a

E

I

(0661)auo@PlPm nu013

XpmS

,poqlaH

sanleA asnuoN ,aasnuoN pue ,slasn jo uos!~edmo3 '01 a l q q

Appendix. Contingent Valuation Studies Since 1980 Measuring Nonuse Value'

.

Author

Good

Boyle and Bishop (1987)

maintaining and restoring bald eagle habitat in WI (the eagle would become extinct in WI without this effort)

Sampled population

Survey administration (response rate)

Payment vehicle

Elicitation method

Mean annual nonuse WTPhh (year of $1, method (m),b sample size (n)

Mean annual use WTPhh, method (m),' sample size (n)

Ratio: nonuse WTP to use WTP*

W I taxpayers who recently contributed to the state's Endangered Resources program

mail (81%)

annual membership in private . foundation for this purpose2

dichotomous choice

$28.38 (na)' m=3 n=86

$46.93' m-3 n=99

0.60

11

n

18

II

$ 18.02

$57.29 rn-2' n=99

'

II

II

m=2aS n-123 I*

same for tho striped shiner (a small, endangered fishI6

#I

Brookshire et al. (1983)

improvement of grizzly bear habitat within 15 years (decline in habitat expected'without action)'

WY hunting license holders who will not hunt grizzly bears2

a#

same, but for big, horn sheep

same, but for big horn sheep2

n

n

n

-

annual payment for a grizzly "stamp"'

"

same, but for big horn sheep'

,

0.3 1

--

$5.55 m-4' n435

na

openended

$15.20 (na) m=2b4 n=170

$5.80 m=2' n=205

2.62

"

$6.90 m=2b4 n=108

$1 1.10 m=2* n=265

0.62

-

mail (-25%)

I

-

-

Appendix. Contingent Valuation Studies Since 1980 Measuring Nonuse Value' Author

Clonts and Malone (1990)

Good

nonuser Alabama residents with phone listings'

preserving 15 Alabama rivers in a free-flowing state

improvement of water quality in Potomac River from useable for recreation to boatable

keep the water quality in Desvousges la et al. (1983) . the ~ o n o n ~ a h e River from slipping back from level D (boatable) to level E (not usable for recreation)

11

Survey administration (response rate)

phone (na)

n

user subset from above'

II

#I

Cronin (1982)'

Sampled population

n

\

Payment vehicle

Elicitation method

Mean annual nonuse WTPhh (year of $), method (m),b sample size (n)

Mean annual use WTPhh, method (m)#' sample size (n)

Ratio: nonuse WTP 10

use WTPd

na

na

$27.50 (1987) m=ll n=630

$16.00 m= l n=630

1.72

n

11

$50.00 m=I2 n=103

$ 19.50 m= 1 n= 103

2.56

Washington, D.C. along Potomac

onsite interview (75%)

na

openended

$35.002 m-2b n=na

$9.00' m=2 n=na

3.89

residents of 5 PA counties in Monongahela watershed who used the river last year'

househol d interview (80%)

annual increase in taxes and prices

openended2

$65.99' (1981j m=3 n=66

$45.30' m=6 n=17

1.46

same, but nonusers last Year

It

n

11

$42.15' m=3 n=139

$ 14.20'

3.97

m-6 n=34

Appendix. Contingent Valuation Studies Since 1980 Measuring Nonuse Value' Author

Good

Sampled population

Survey administration (response rate)

Payment vehicle

Elicitation method

Mean annual nonuse WTPhh (year of $1, method (m),b sample size (n)

Mean annual use WTPhh, method (m),' sample size (n)

Ratio: nonuse WTP to use WTP~

Desvousges et al. (1992)

protecting specified number of waterfowl in the Central Flyway fiom drowning in waste-oil holding ponds by covering the ponds with wire netting'

adult nonstudent shoppers in Atlanta GA

distribute and complete onsite (na)

annual price increase

openended2

$59.00 to $7 1.003 (199 1) m-4' n=398 to 408'

na

--

Diamond et al. (1992)

protect specified wilderness areas in CO, MT, ID, or WY fiom timber harvest, given that 7 of the 57 designated wilderness areas in those states are already proposed for harvest

CO, MT, ID, and WY residents with phone listings

phone (62%)

annual federal income tax surcharge to respondent's household

openended

$23.27 to $58.54' (199 1) m-4' n=144 to 151'

na

--

Dufield (1992)

support recovery of wolves 61Yellowstone National Park (find essential to recovery)'

visitors to the park

distribute onsite, return by mail (3 1%)

lifetime membership in trust fund

dichotomous choice2

$17.39' (1990) m=3 11-457

$5.48' m=3 11-450

3.17

Duffield et al. (1993)

buy water to increase summer flows in selected MT rivers, to improve , habitat and recreation'

residents of 6 urbamareas in MT and WA with phone listings

mail . (34%)

annual membership in a special trust fund

dichotomous choice2

$4.07 (1988) m=2a3 n=254

$9.97 rn-2 n=269

0.4 1

Appendix. Contingent Valuation Studies Since 1980 Measuring Nonuse Value' Author

It

Good

Sampled population

II

-

Survey administration (response rate)

I,

. Payment vehicle

I1

I1

n

I,

I1

It

I1

I1

II

I1

It

I1

I,

II

same, but only users7

I1

- -

Gilbert et al. (1992)

11

protection and yanagement of Eastern . wilderness areas (assuming budget ,cuts efirninated all public finding and protection)' II

same, but only nonusers' residents of southern Vermont and parts of surrounding states2 II

Mean annual nonuse W T P M (year of $1, method (m),b sample size (n)

Mean annual use WTl3/hh, method (m),C sample size (n)

Ratio: nonuse WTP

$7.14' m=5 n-554

$2.26' m=5 n=554

3.17

$9.33 m=2a3 n=103

$6.54 m=2 n= 124

1.43

$ 1 1.39

m=5 n-227

$1.556 m=5 n=227

1,

f 10.47 m=18 n= 124

$5.40 m=ll n=124

1.94

11

$7.37 m=19 n=103

$2.7 1 m=19 n-103

2.72

dichotomous choice'

$6.40

(1990) m=2a4 n-78

$7.88 m-2 n=108

0.8 1

openended'

$4.78 m=l n=195

$2.32 m= l n=195

2.06

I1

-

It

11

Elicitation method

..

I1

I1

-

II

--

mail

'

use WTP~

-

:'

7.32

-

I1

(-27%)

18

openended'

10

annual contribution to a special trust find

n

Appendix. Contingent Valuation Studies Since 1980 Measuring Nonuse Value' Author

Greenley et al. (1981)'

11

Haefele et al. (1992)

I#

Good

postpone mining that would degrade water quality throughout the South Platte Basin (CO) enough to permanently preclude riparian recreation (3 photos used) I1

protection programs (against insects and air pollution) for spruce-fir forests along roads and trails in the southern . Appalachian Mountains (3 photos used)' IS

Sampled population

Survey administration (response rate)

Payment vehicle

Denver and Fort Collins residents expecting to use sites for recreation in the future

househol d interview (na)

annual increase in sales tax payments' '

same, but future nonusers

II

residents within 500 miles of Asheville, NC, with phone listings

mail (51%)

mail (53%)

I@

.

--

II

annual increase in taxes put into a special conservation fund

II

.--

Elicitation method

Mean annual nonuse WTPmh (year of $1, method (m),b sample size (n)

Mean annual use WTPhh, method (m)lc sample size (n)

Ratio: nonuse WTP to use WTP~

bidding game

$67.0O3(1976) m=3 n= 174

$79.28' m=6 n-174

0.85

11

.

--

$4 1.95' m=3 n-24

na

dichotomous choice

$50.75 (1991) m= 1 n=306

$7.58 m= 1 n=306

6.70

payment card

$15.93 (1991) m= l n=3 18

$1.48 m= l n=3 18

10.74

,

Appendix. Contingent Valuation Studies Since 1980 Measuring Nonuse Valuea Author

Good

Sampled population

Survey administration (response rate)

Payment vehicle

Elicitation method

Mean annual nonuse WTPkh (year of $1, method (m),b sample size (n)

Mean annual use WTP/hh, method (m),' sample size (n>

Ratio: nonuse

WTP lo use WTP~

Hageman (1985)

avoid reduction in California sea otter population from current level to a level that would eliminate chances of seeing the animal and could endanger the population'

California residents with phone listings

mail (2 1%)

annual flat tax paid by all U.S. households, plus an additional personal contribution2

payment card

$13.62 (1984) rn= l n=- 173

$7.20 rn= l n=-173

1.89

Hagen et al. (1991)

protect northern spotted owls and their old-growth habitat in the Northwest

U.S.

mail (39%)

annual increase in taxes and , wood product prices

dichotomous choice

$86.32 (1990) m-l n-394

na

--

Hoehn (199 I)'

83% improvement in air quality at the Grand Canyon'

Chicago residents

househol d interview (na)

monthly payment to an air quality program

several'

S82.794J (1980) m 4 n=182

na

--

King et al. . (1986)

certain survival of a nearby herd of big horn sheep that would be lost with certainty without action

Tucson, AZ residents with phone listings listings

mail (59%)

annual membership in organization that would protect habitat

openended

$15.14 (1985) m=3 11-500

$2.00 m=3 11-500

7.57

Loomis (1987a)'

certain improvement in water level in Mono Lake, with associated water quality and habitat improvements

CA residents with phone listing1

mail (44%)

monthly water bill'

dichotomous choice

$80.48' (1986) m= 1 n=- 160

$14.20 m= l 11-160

5.67

residents

Appendix. Contingent Valuation Studies Since 1980 Measuring Non~~se Value' Author

Good

11

n

Mitchell and Carson (198 1)'

Sampled population

Survey administration (response rate)

Mono Lake visitors contacted onsite

distribute onsite, return by mail (84%)

improving water quality in all U.S. river and lakes (from a current unspecified level) to fishable level

national household survey

househol d interview

guaranteed doubling of Columbia River Basin salmon and steelhead fish runs

Pacific Northwest residents with phones

phone (72%)

monthly increase in electric bill'

openended

$26.52 (1989) m=2a,b2 n=-300"

$47.64' m=2 n=390

0.56

avoid a decrease in air quality and visibility at the Grand canyon'

Denver residents

househol d interview (na)

monthly increase in electricity bill

openended

$47.52' (1981) m= 1 n=75

$13.44 m= l n=75

3.54

assure continued.existence of the northern spotted owl

WA residents with phone listings.

mail (23%'

annual payment'

payment card

$49.72 (1 987) m=42 n=216

na

Payment vehicle

"'

annual increases in prices and taxer

Elicitation method

Mean annual nonuse WTP/hh (year of $1, method (m),b sample size (n)

Mean annual use WTP/hh, method (m),' sample size (n)

Ratio: nonuse WTP to use WTPd

n

5160.19" m= 1 n=-I 00

$41.81 m= 1 n=-100

3.38

payment card

$1 1 1 .002 (1981) m=2a n=?'

$ 126.00

0.88

m=2 n=?

Olsen et al. (1 99 1)

Rahmatian (1 987)

Rubin et al. (1991)

.

--

Appendix. Contingent Valuation Studies Since 1980 Measuring Nonuse Value' Author

Good

Survey adrninistration (response rate)

Sampled population

Elicitation method

Payment vehicle

Schulze et al. (1983)

prevent a specified deterioration in visibility from the current average in parklands region (photos used)'

residents of Albuquerque, Los Angeles, Denver, and Chicago

househol d interview (na)

monthly increase in electric utility bill

payment card

Silberman et al. (1992)

quantified restoration and maintenance of selected northern NJ beaches damaged by recent erosion (photo used)

current users of selected nearby beaches, expected fiture users

onsite interview (na)

one-time contribution to a non-profit foundation, which would also collect entrance fees'

bidding game

same, but fiture nonusers

n

Northern NJ and Staten , Is. residents who don't use the selected beaches but will in future

phone (na)

-

-

-

~

same, but no photo used'

same, 'but future nonusers

openended

i ,(

11

Mean annual nonuse WTPhh (year of $11 method (m),b sample size (n)

$15.212(1985) m=6

Mean annual use

WTP/hh, method (m),S sample size (n)

1

na'

Ratio: nonuse WTP t0

use

WTPd

Appendix. Contingent Valuation Studies Since 1980 Measuring Nonuse Value' Author

Good

Stevens et al. (1991)

Sampled population

mail (30%)

preserve and protect bald eagles in New England (extinction in region is assured without action)'

New England residents

Stoll and Johnson (1985)

effort to preserve essential whooping crane habitat (extinction certain without this effort) & exclusive entrance to refige areas

visitors to Aransas National Wildlife Rehge in TX

I#

n

I-'

16

vl

Sutherland and Walsh (1985)

Walsh et al. (1984)

'

Survey administration (response rate)

Payment vehicle

Elicitation method

Mean annual nonuse WTP/hh (year of $1, . method (m),b sample size (n)

Mean annual use WTP/hh, method (m),' sample size (n)

Ratio: nonuse

WTP to use WTP*

annual payment for the next 5 years to a private trust fund'

openended'

$15.81 (na) m= 1 n=-85

$3.47' m=1 n=-85

4.56

distribute and complete onsite (67%)

annual membership in foundation that would work for crane preservation

dichotomous choice

$9.33 (1983) m=2b2 n=30

$7.54 m=2 n-3 5 1

1.24

TX residents

mail' (36%)

It

a#

$1.03 m=2b n=73

$9.64 m-2 n=176

0.1 1

maintain water quality in Flathead Lake and River (in Montana) at current (pristine) level

residents of 4 Montana cities with phone listings

mail (61%)

annual payment to special fund for protecting water quality in the area

openended

$46.25' (198 1) m=1 n=171

$18.08 m= l n=17 1

2.56

protect 10 million acres of potential CO wilderness from certain development, allowing time for an informed decision about wilderness designation

Denver and Fort Collins residents

mail (41%)

annual payment to a special fund'

openended

$22.60 (1 980) m= I n=195

$23.23 m= 1 n=195

0.97

..

.

Appendix. Contingent Valuation Studies Since 1980 Measuring Nonuse Value'

guaranteed protection of 11 specified rivers (development will begin without pr~tection)~

Walsh et al. (1985)'

la

,

It

CO resident nonusers'

protection of specified level of live trees from insect damage in 11 CO national forests (3 photos used)'

Fort Collins residents with phone listings

preserve Clear Creek wetland (a large bottomland hardwood forest wetland in western KY) from potential development for surface coal mining

KY residents with phone listings with . prior information about KY wetlands'

-

I#

Survey administration (response rate)

mail (51%)

user subset from above4

#I

Walsh et al. (1990)

Whitehead and Blomquist (1991)

Sampled population

Good

Author

I#

househol d interview

Payment vehicle

annual payment to a special trust find #I

Elicitation method

openended

I#

Mean annual nonuse WTP/hh (year of $1, method (m),b sample size (n)

Mean annual use WTPIhh, method

Ratio: nonuse

(m),'

to use

sample size (n)

WTP

WTP~

$22.00 (1983) m=l n=40

$6.00 m= 1 n=40

3.67

$56.00 m= 1 n-59

$53.00 m= I 11x59

1.06

1.04

annual increase in taxes and prices3

bidding game

$24.00 (1983) m=l n=198

$23.00' rn- l n-198

annual contribution to the Wetland Preservation Fund for Clear Creek wetland

dichotomous choice

$17.48 (1989) m=2a2 n=118

na

(-67%)' mail (31%)

-

same, but without prior information

#I

lo

I@

$5.56 m=2az n=96

'

I#

--

--

I Appendix.

Sampled population

Whitehead and Groothuis (1 992)

\O

u

1

Contingent Valuation Studies Since 1980 Measuring Nonuse Valuea

reduction in nonpoint . source pollution in TarPamlico River (NC) allowing anglers to catch twice as many fish per

residents of counties in Tar-Pamlico basin

Survey administration (response rite)

Payment vehicle

I annual contribution to a preservation find for compensating . farmers who use pollution control practices

Elicitation method

openended

.

Mean annual nonuse WTPhh (year of $1, : method ( m): sample size (n)

Mean annual use WTP/hh, method (m),= sample size (n)

Ratio: nonuse WTP to use WTP~ 1.50

'na" indicates not available (not reported); I" indicates hou! "Nonuse value" refers to %TP ior therknowledge that a thing exists (usually called "existence value") and for the desire to make the thing available for otllcr (usually called "bequest value"). "Use value" refers to WTP for current and future use, and for the option of future use (usually called "option value"). Nonuse values were estimated by one of six methods: 1. asking respondents to allocate their total value into categories of value (nonuse value includes existence and bequest value), or asking a separate qucstioi about nonuse value; 2. asking total WTP to a sample including only persons who (a) had not used the resource or (b) would not use the resource; 3. asking total WTP to respondents who are asked to assume that they would not use the resource; 4. assuming all respondents are nonusers; 5. statistically separating total value into categories of value based responses about relevant attitudes and behavior; . 6. asking separate questions about nonuse value. ' Use values were estimated by one of five methods: 1. asking respondents to allocate their total value into categories of value (use value includes option value); 2. the difference: total WTP of the subsample who reported that they had or would use the resource minus total WTP of the subsample who reported they had not or would not use the resource (where the latter is listed in the nonuse column); 3. the difference: total WTP when respondents are assumed to use or have the option to use the resource minus total WTP when respondents are asked to assume that they will not use the resource; 4. there is no value counterpart to nonuse value method 4; 5. statistically separating categories of value based responses about relevar~tattitudes and behavior; 6. asking separate use value questions. 7he components for this ratio are taken fidm the two columns to the left. Note that the ratios reflect various methods of separating use fro111 nonusc WIT.

,,-J~A!J aql asn 1aAau plnom,, Xaql amnsse 01 alaM auapuodsa~'anle~a3uajs!xa JOJ -sluapuodsa~ 01 paquxap Xl[ya~:,slam anlerz jo sa!lo%alm aualaya .anleA a~uais!xa~ o pasn j SEM uo!isanb papua-uado us Aluo a s n q a a q papodar am sasuodsa~papua-uado aql AIUO ' a l q q a ~uo %u!puadap Xlap!~ p a p h sasuodsax - p m ~ u a d e d(p) pue 'uopsanb papuauado (Q 'lyod 8 u ~ m SZI$ s ~ I ! M a m %%mpp!q (z) ' i ~ o d% u ~ mSZ$ s qam\+w~~% Ou!pp!q (I) 01 papuodw a q s pnba Alateqxo~ddej o salduresqns 'anle~am JOJ =rea6 1sed ay) u! JaAu ayl %msnu o d a ~~ o up!p Latp J! uana 'anpn am e pappold oqm asoq are slam se papnpy o q y (£861) 'Ie la =%sno~aa

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*.raAu dn-paueal:, e am plnom JO u a m ~ulsardare oqm snos~adJOJ sem ( 0 0 . ~ ) 1~]ot,srasn 'aq 01 q aqq plnom Aaq se neap se-aram I! J! uaha xmolod a q asn 1ou ppom Law p!es o q suoslad ~ 103 s! a n p asnuou a u *.~aq~nex p w laqsy jo s a1m UIOJA *uo@u!qsefi 'puelq3!~'rClomoqg ~ s a ~ q =y!zd u o ~ ,,'k!pnb Jawm p a ~ o ~ d ml o! j s a n p auais!xa pue 'uo!ldo 'asn aql Bu!i~mpsg, pappua laded (2861 u!) %u!uxm~~.'oj e '~UOQ Xq laded layiow moy Lmmuns q a y j o amos ayel,osle oqm '(~861)iaqsney pue ~ a q s X ! q~ pauodar.sy (286 1) U!UOJ3

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.sreaA aanla lsel aqa u! slaAu SI aqa JO a ~ o wJO auo pasn peq mqruam p ~ o q m o qe pqa pavodar oqm aldumqng 'Xpws 1 poqIaru e Xlp!auassa s!tp % u g e u ~ pay= slam sluapuodsa~u a q ! a n p a u a q x a p w ' s a n p paurns pue'@np!ypu! aqa QWA 01 sam!1 'anje~lsanbaq ' a n p uoydo 'am JOJ u o d a 01 suoysanb %mpp!q alwedas y payse sem luapuodsx q q 51 a q j o Lue pasn 1ou peg iaqmam ploqasnoq e t e y ~pavodar oqm alduresqns (0661) auo@K P a Quo13 'srea6 a a w lse[ aqj u! =nu

,

. a n p auaiqxa opnlsy sp!q ,spsn l e g samnsse u!alaq z poyam sealaqm - a n p muapxa ou pauyucn =sn j o sp!q ayl wqa paurnsse u o q m ayl leqa aloN 'sapads aqj lung 01 ueld IOU p!p oqm suosrad Xq s a ! d s aqa j o uophlasqo loj sem a m yqa y asn .sa!mds aqa auasqo ot ~ m d x aIOU p!p oqm sauapuodsax .uo!tnqyum e 01 re~!u~!ssem d w s aql JO aseqand aeyl u!aaq paumsse s! 11 -am- L ~ V O eM01 p31nqyum peq laploq atp P ~ a%palmouy I aqj ueqa i a q ~ o'pap!~o~dduws aql pqm anoqe map IOU s! uodal aqa '(aaq pauoda~alnsal a q ) slalunquou a.wy JOJ ' J ~ A ~ M O H-%upunqJOJ pa+nba! sem dure]s s!q pq reap s! voda~aql 'sapads a q g o sra~unqawry JOJ .sapads arl, lunq 01 pauadxa oqm suoslad JOJ sllnsar s u y u m osp uodar a u -maX aAg u!tp!m pa~a!qz~enuama~o~dm! m!qeq ~ o sllnsal j su!eauo:, osle uodal a u I (£861) 'le P al!WiooJa

,

,

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,

,

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-uo!isanb ayoq3 snou101oq3!p aqa pamolIoj uoysanb papua-uado q '5 poqlam %u!sn (€661) *pla p l a g n a Xq pavodai suo!lenba moj a g % u o w saleuysa ( ~ 1 . 8 9 )MOI pm ( % L z ~ ) q8!q aql uaawaq ~u!odp!u aqa s! % g a~ u w a l a i q asnuou 01 alqelnqym sew (paurqmm sa~duresqnsJarlu -S pue a[8u!s aql p m 'srasnuou pue slasn ~sed)sauapuodsa~1p jo aj o % g n~q l aumsse a a q sayua a u .'sreaA E ise1 atp u!,, (s)larlu pay3ads atp p a g s ! ~IOU peq o q sluapuodsax ~ '1% Xed plnom Xayl j! payse aram lrmoure papod a q Xed 08 %UKII!M lou slam oqm sauapuodsax 'aloH s!ff

pue ~ o o u a n !a ~q papnpu! pq srarlu emuoyq uralsam ahy JO p s e no p q ayl pue ' l a h ~aIoH %!aa q uo Jaqoue ' ~ a r l !loonan!a ~ ..'arl) no pasn:,oj auo fsa~duresqnsaarq~jo n o p u ~ q m me JOJ am araq paluasard q n s a x

,

,

(£661) '@ p PIaBW

,,"'auotswo~~a~ u! JIOM e m q 10aas 01 p%~@!m X1puosrad noX pyl "' asoddng,, p ~ o slam l sauapuodsax , -mueam $on 'a~aqpatroda~s! ,-JJ.M ue!paul pyl a l o ~ ,;sarllom m q JO aas 01 &!uwoddo m arleq iou plnom Xl~euosladnoK n t p "' asoddng, plo1 aram auapuodsay.u!aJaq pauodai ale sa1nsaJ m!oq:, snomoloq3!p aqa Xluo lnq 'pwo11oj uogsanb papuauado u~ -1%Xed plnom bgj! payse aiam lunoure pa~!sod a g Xed 01 %u!ll!m IOU sauapuodsax pauo!~uam sew sarl~owayl jo a s n q s[em!ue Jaylo j o s s o ~pue pauo!luam a a f i (pal!un[un q 3 n a ' h u e ~ a s u o = a) r n 3 e ~ayl '.%.a) s p q JSW ~ a r p

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