factors influencing differences between survey and market based environmental value measures a unique us database combining survey and housing data is used to obtain household level stated and market based willingness to pay wtp measures to avoid living near landfills systematic differe

the theory of mixed demand functions abstract the properties of samuelson s mixed demand functions which express demand as a function of a mixed set of prices and quantities are derived by analyzing compensated or substitution effects and uncompensated effects the relationships between mixed demand functions and conditional or rationed demands are examined this provides insights on the behavioral implications of consumer theory for alternative demand specifications

deriving a flexible mixed demand system the normalized quadratic model this article deals with the specification of a locally flexible and theory consistent system of mixed demand functions a framework that allows for a rich set of possibilities about what is assumed as exogenous in a demand model a coherent mixed demand system is derived by using the restricted expenditure function typically studied in the related area of rationed demands the method is implemented by a new normalized quadratic nq parameterization of the restricted expenditure function the resulting nq mixed demand system is illustrated with an application to a nine good model of the italian demand for vegetables

public goods as characteristics of non market commodities in benefit cost analysis it is useful to model public goods as the quality of privately consumed nonmarketed goods this strategy is often pursued in valuing environmental amenities the theoretical foundations of this model have not been fully developed in this paper comparative statics results are derived for quality changes of nonmarket goods the results reveal some common misconceptions about welfare measurement of quality changes conditions are presented for a quality induced change in the marshallian consumer surplus of the nonmarket good to approximate the true compensated welfare measure the conditions are equally necessary for obtaining exact welfare measures copyright 1993 by royal economic society

comment on cameron s censored logistic regression model for referendum data abstract t a cameron a new paradigm for valuing non market goods using referendum data maximum likelihood estimation by censored logistic regression j environ econom management 15 355 379 1988 presents what she terms a new paradigm for interpreting referendum data derived from contingent valuation surveys for nonmarket resources we show that since her model is a reparameterization of the usual logistic regression model asymptotic standard errors can be derived for the maximum likelihood estimators of the parameters in either model from the other we also argue that computational convenience in deriving demand relationships or elasticities depends more on the choice of welfare measure than on the choice of a parameterization

separability partial demand systems and consumer s surplus measures abstract in practice complete demand systems are not estimated rather either an incomplete demand system is estimated or separability is invoked and a partial demand system is estimated this paper considers the relationship between the conventional compensating variation equivalent variation and the corresponding welfare measure that can be derived from a partial demand system and the current budget allocation to the separable group even assuming the separability assumption invoked is appropriate these partial measures provide in general only a limited amount of information about the compensating variation and no information about the equivalent variation great care is therefore needed when using partial welfare measures to evaluate policy

monte carlo benchmarks for discrete response valuation methods this paper argues that the belief that discrete contingent valuation cv questions yield substantially larger estimates of the mean and the median willingness to pay wtp for nonmarket resources in comparison to open ended cv questions is unfounded monte carlo experiments estimate the factors influencing the performance of wtp estimates based on discrete response models most of the error arises from the specification errors common to the empirical models in the literature these experiments suggest models where wtp is dominated by nonuse or passive use values are likely to have smaller errors than where large use values influence these decisions

estimating willingness to pay for a cycling event using a willingness to travel approach abstract this study examines the monetary value of nonmarket benefits to participants of an active sport tourism event such as happiness and pride from participating in an event willingness to travel wtt greater distances for future events is assessed and converted into willingness to pay wtp estimates using travel costs using survey data from the 2014 and 2015 blood sweat gears bike ride the intended visitation models show that changes in travel cost have a significant negative effect wtp to revisit the event was between 41 and 57 the likelihood of return visit decreases as travel costs increase indicating that wtp estimates are internally valid wtp estimates stemming from two years of data collection are stable suggesting that they are also temporally reliable this study demonstrated the feasibility of using stated preference wtt questions to assign a monetary value to nonmarket benefits of active sport tourists

the individual travel cost method with consumer specific values of travel time savings the treatment of the opportunity cost of travel time in travel cost models has been an area of research interest for many decades our analysis develops a methodology to combine the travel distance and travel time data with respondent specific estimates of the value of travel time savings vtts the individual vtts are elicited with the use of discrete choice stated preference methods the travel time valuation procedure is integrated into the travel cost valuation exercise to create a two equation structural model of site valuation since the travel time equation of the structural model incorporates individual preference heterogeneity the full structure model provides a travel cost site demand model based upon individualized values of time the methodology is illustrated in a study of recreational birdwatching more specifically visits to a stork village in poland we show that the usual practice of basing respondents vtts on 1 3 of their wage rate is largely unfounded and propose alternatives including a separate component of the travel cost survey aimed at valuation of respondents vtts or as a second best asking if they wish if their journey was shorter and for those who do use full hourly wage as an indicator of their vtts

utility consistent discrete continuous choices in soil conservation a utility consistent model of participation and participation intensity choices for a voluntary soil conservation program is developed a modified form of roy s identity is used to derive a two equation system that links the discrete dichotomous choice participation and the continuous choice intensity to the same utility function the model corrects for selectivity bias that arises in single equation approaches an application to a filter strip program in two counties in illinois and michigan demonstrates that different factors affect responses to the program across the sample regions estimated willingness to accept payments for participation in the program suggest policy impacts are not uniform across locations

a note on choice of residential location in travel cost demand models where x is number of visits to a site p is price y is a k x 1 vector of observed individual characteristics and e is a random component 1 is a 1 x k parameter vector and p is a scalar parameter hundreds of models with this basic demand relationship as a basis have been estimated see smith s 1989 review my concern is that the price used in this model may be endogenous because people base decisions about where to live in part on proximity to recreation sites if so unobserved taste characteristics in the error term e will be

valuing environmental resources through demand for related commodities we examine the revealed preference theory underlying the welfare analysis of public goods e g environmental quality by observing the consumption of related commodities inspired by larson 1991 and ebert 1998 and extended from eom and larson 2006 an empirical strategy is formulated consistent with the theory of uniquely deriving use and nonuse values for a change in the public good we show that the weak complementarity assumption and the willig condition the common preference assumptions used to support the revealed preference methods for non market valuation may be tested as parameter restrictions a study of water quality valuation is presented to illustrate the proposed empirical strategy results show that the weak complementarity assumption and the willig condition generally do not hold in the case study and the consumer surplus derived from the indirect valuation method deviates largely from the exact welfare measures

determinants of participation in accelerated vehicle retirement programs one potential way to reduce hydrocarbon emission is through accelerated vehicle retirement programs however it is difficult to forecast participation rates in these programs because the number and characteristics of participants are likely to vary with the price offered to attract old cars this paper presents a theoretical model of the owner s car tenure and scrappage decision an econometric model of participation is then developed and estimated using data from a recent old vehicle scrap program in delaware participation rates at different possible offer prices are then predicted

demand fluctuations in the ready mix concrete industry i investigate the role of demand shocks in the ready mix concrete industry using census data on more than 15 000 plants i estimate a model of investment and entry in oligopolistic markets these estimates are used to simulate the effect of eliminating short term local demand changes a policy of smoothing the volatility of demand has a market expansion effect the model predicts a 39 increase in the number of plants in the industry since bigger markets have both more plants and larger plants a demand smoothing fiscal policy would increase the share of large plants by 20 finally the policy of smoothing demand reduces entry and exit by 25 but has no effect on the rate at which firms change their size

sparkling wine choice from supermarket shelves the impact of certification of origin and production practices we report the results of a study based on revealed and stated preference data on choice of prosecco wines in retail stores close to the origin of production in northern italy emphasis is placed on ability to reconcile the utility structure of stated preference data with that underlying revealed preference data we extend the analysis to cover nonattendance of key attributes such as price and certification of origin while controlling for the large range of brand effects

perceptions versus objective measures of environmental quality in combined revealed and stated preference models of environmental valuation abstract this study examines perceptions and objective attribute measures in discrete choice models of recreation site choice behavior these forms of attribute measurement are examined in individual and combined revealed preference stated preference models our results suggest that the model based on perceptions slightly outperforms the models based on objective attribute measures however issues such as the definition of the choice set and the measurement of welfare present significant challenges when using perceptions data

combining revealed and stated preference data to estimate the nonmarket value of ecological services an assessment of the state of the science this paper reviews the marketing transportation and environmental economics literature on the joint estimation of revealed preference rp and stated preference sp data the rp and sp approaches are first described with a focus on the strengths and weaknesses of each recognizing these strengths and weaknesses the potential gains from combining data are described a classification system for combined data that emphasizes the type of data combination and the econometric models used is proposed a methodological review of the literature is pursued based on this classification system examples from the environmental economics literature are highlighted a discussion of the advantages and disadvantages of each type of jointly estimated model is then presented suggestions for future research in particular opportunities for application of these models to environmental quality valuation are presented

low energy efficiency in rental properties asymmetric information or low willingness to pay abstract asymmetric information may explain low energy efficiency in rented properties energy ratings while a solution to the information problem will only lead to higher efficiency levels if renter s willingness to pay wtp exceeds landlord s investment costs using a sample of renters from one university this paper estimates this wtp using a discrete choice experiment where respondents choose from a hypothetical set of single bedroom apartments that differ according to a number of attributes including the energy rating results show that there is a strong disutility associated with the least efficient properties and that renters will pay significantly more for efficiency improvements at the lower end of the efficiency scale importantly our wtp estimates are calculated in a setting where respondents were informed about the energy rating system prior to choosing and where the rating was shown for every property therefore in order to maximise the impact of energy rating systems policymakers are encouraged to ensure that both these informational characteristics are in place

state abortion rates the impact of policies providers politics demographics and economic environment abstract this paper uses data on abortion rates by state from 1974 1988 to estimate two stage least squares models with fixed state and year effects restrictions on medicaid funding for abortion are correlated with lower abortion rates in state and higher rates among nearby states a maximal estimate suggests that 19 25 of the abortions among low income women that are publicly funded do not take place after funding is eliminated parental notification laws for teen abortions do not significantly affect aggregate abortion rates a larger number of abortion providers in a state increases the abortion rate primarily through inducing cross state travel

an economic analysis of the demand for abortions research in estimating the demand for abortions is conducted by using an economic model and examining socioeconomic factors some suggest that a households fertility control decision is decided by a comparison of the costs and benefits of an additional child over a period of time therefore abortion is a choice related to the interaction of preference cost and income a womans marital status is another factor in the abortion decision an unmarried women may having a greater demand for abortion since the demands on her are greater another factor is a womans employment status an employed woman more likely having a higher abortion religious affiliation may be another determinant in lower demand for abortion since most religions oppose abortion however in surveys of catholic women 74 believed that a woman less than 3 months pregnant should make her own choice on abortion educational status was also thought to effect abortion demand but results showed no significance if the laws were changed abortion were illegal and the price increased 50 the abortion rate would drop by 40 5 the prohibiting of government funding for abortions would cause a 17 5 decrease future trends in abortion are likely to increase however due to the declining marriage rates and increased divorce rate other factors that will effect these trends include sexual behavior patterns contraceptive availability and the perceived risks involved in birth control

willingness to pay for curbside recycling with detection and mitigation of hypothetical bias in this article we estimate willingness to pay for curbside recycling using a unique data set we also test for and detect significant hypothetical bias using stated and revealed preference data a short scripted cheap talk statement is used to mitigate the bias and provide more efficient estimates of the welfare impacts of curbside recycling programs copyright 2003 oxford university press

a difficulty with the travel cost method instead of observable prices of recreational visits travel cost method tcm re searchers are obliged to substitute researcher assigned visitation cost estimates i argue that visitation costs are inherently subjective but are ordinally measurable so long as the cost in creases with distance travelled it follows that traditional tcm yields only ordinally measur able welfare estimates the household produc tion function formulation of tcm resolves this problem only by imposing severe and un testable analytical restrictions tcm cannot serve as a stand alone technique for estimating recreation benefits rather it must be calibrated using information generated with fundamentally different methods jel q26

an empirical investigation into students experience of fuel poverty abstract the trend of expansion in higher education in the uk since 1992 has created a massive demand for accommodation for students where the housing stock is one of the oldest and least efficient in europe and the private rented sector is often singled out for containing some of the least energy efficient and in worst condition properties the extent to which students factor in energy efficiency and fuel poverty concerns into their accommodation choices is explored in this paper along with the perception of the phenomena by students from a survey of 286 students it was revealed that while students themselves may not consider themselves to be living in fuel poverty the activities taken in their day to day lives suggest the opposite the impact of the housing stock on student quality of life is investigated as well

the relationship between the income elasticities of demand and willingness to pay abstract the relationship between income and willingness to pay for collectively provided public environmental goods is investigated we show that while the income elasticity of willingness to pay and the ordinary income elasticity of demand are related knowledge of one is insufficient to determine the magnitude or even the sign of the other the income elasticity of willingness to pay is influenced by additional factors which are generally unobservable examples are provided to illustrate the degree to which the two income elasticities may diverge our results indicate that even when goods are demand luxuries they may or may not have income elasticities of willingness to pay which are greater than one

weak separability in applied welfare analysis the focus of this paper is the impact on welfare measurement of a common assumption in applied demand analysis weak separability a standard empirical practice is to estimate conditional demand models for a set of goods which are assumed to be weakly separable from all other goods with expenditure as a right hand side variable tacitly assuming that expenditure is predetermined alston and chalfant 1987 1991 alston carter green and pick blackorby boyce and russell blisard and blaylock brown and heien cashin choi and sosin clements and e selvanathan clements and s selvana than deaton 1975 goddard and amuah gould cox and perali 1990 1991 heien heien and pompelli 1988 1989 murray safyurtlu john son and hassan theil 1976 1980 van ko oten yen and chern once estimated such separable demand models often are used to cal culate exact welfare measures or changes in the true cost of living index of the economic effects on consumers due to changes in the prices of the goods under study heien heien and pom pelli 1989 van kooten blisard and blaylock this practice is shown here to produce biased results there are two sources of the bias and both can be traced to the inappropriate treatment of expenditure as predetermined in an empiri cal application to the u s dairy program a comparison of estimates from an incomplete demand system specification versus a weakly separable specification suggests a negative bias of around 17 of the compensating variation due to eliminating price discrimination in federal milk marketing orders in 1990 results from a monte carlo simulation suggest that the downward bias is closer to 40 i first present the analysis of weak separability then the empirical application and a summary and conclusions this abstract was borrowed from another version of this item

fuel poverty and energy efficiency obligations a critical assessment of the supplier obligation in the uk energy efficiency obligations or white certificates are increasingly used to reduce carbon emissions while the energy efficiency obligations were originally intended as carbon reduction and not fuel poverty policies due to recognition of the potential for regressive outcomes they often include provisions for vulnerable and low income customers intuitively reducing carbon emissions and alleviating fuel poverty seem to be two sides of the same coin there are however considerable tensions between the two when addressed through energy efficiency obligations particularly arising from the potentially regressive impacts of rising energy prices resulting from such obligations but also the complexity of targeting fuel poor households and the implications for deliverability despite those tensions the uk government decided to use energy efficiency obligations the supplier obligation as the main policy for reducing fuel poverty in light of the proposals this paper provides an analysis of the main tensions between carbon reduction and fuel poverty alleviation within energy efficiency obligations outlines the fuel poverty provisions of the british supplier obligation assesses its rules for identifying the fuel poor and provides a critical analysis of the planned policy changes based on this analysis alternative approaches to targeting fuel poverty within future supplier obligations are proposed

willingness to pay for quality improvements comparative statics and interpretation of contingent valuation results this paper extends variation function theory by examining the effects of changes in prices quality and income on willingness to pay for quality change comparative static effects are found for both on site users and nonusers of the resource these results are used to interpret contingent valuation empirical models for example the substitution and complementary relationships between trips to natural resource sites can be identified this paper also suggests tests for comparison of contingent valuation with recreation demand models and other tests of validity

delivering energy efficiency and carbon reduction schemes in england lessons from green deal pioneer places against a background of growing international and national carbon reduction legislation the uk government introduced the green deal to deliver a significant increase in housing energy efficiency and reduction in carbon emissions this paper reflects on one english local authority s experience delivering a programme intended to foster local interest in the green deal drawing on social surveys and pre and post green deal intervention interviews with five demonstrator homes households that applied to receive a green deal package fully funded by the scheme providing a test bed for the green deal recruitment and installation process this paper shows that awareness and understanding of the green deal scheme is low there is opposition to the cost of finance offered but a strong interest in improving household warmth and for funding improvements through payments added to the electricity bill demonstrator home residents perceived green deals had improved the warmth and quality of their home but saving money was the primary motivator for their involvement not increasing warmth whilst green deal has not delivered the level of success that was hoped much can be learned from the scheme to improve future energy efficiency schemes that will be necessary to deliver emission reduction commitments

teen motherhood and abortion access it is argued that the net effect of any restriction of abortion access on birth rates is an empirical question this study examines the impact of access to abortion on county teenage birth rates birth rates are expected to decrease by 1 among white adolescents aged 15 19 years for a 25 mile increase in the distance to the nearest abortion provider particularly among in wedlock births data are obtained from 1973 88 national natality local area summary files for counties in the us and four other national sources data did not provide useful information on the empirical relationship between access and birth rate for densely populated urban areas cross sectional findings that had omitted variable bias indicate that an increase of 25 miles in distance to a provider was associated with an additional 1 4 births per 1000 white teenage women or a 3 increase in the average teen birth rate of 45 1000 white teenagers the findings from a county fixed effects model that controlled for omitted variable bias indicate that an increase of 25 miles was associated with a reduction in teen births of 0 5 1000 or about 1 of the mean birth rate both medicaid restrictions and parental consent laws were negative and significant and more negative in poor and more isolated counties the state year effects models did not change findings on distance and medicaid restriction effects the effects of changes in timing of laws suggests that laws followed preexisting trends changes in distance to provider were primarily in the first 2 years following the change out of wedlock births were unaffected by changes in distance to providers the out of wedlock teen birth rate increased with a complete ban on abortions fewer wanted births were associated with small restrictions findings imply that closing of clinics during 1977 88 had an impact on teen birth rates of under one tenth of 1 the 20 increase in teen births was unexplained

precision of dichotomous choice contingent valuation welfare measures some simulation results the purpose of this research is to examine the roles of individuals heterogeneous economic factors and model misspecification in dichotomous choice contingent valuation welfare measurement willingness to pay for an improvement of environmental quality is studied simulation results indicate that the precision of welfare estimates increases with individuals income levels and decreases with the price of the quality related good the dependence of the consumption of the quality related good on the environmental quality also affects the reliability of welfare estimates

estimating the demand for a new technology bt cotton and insecticide policies this article examines the potential demand for bt cotton in the southeast from information gathered in the first year of commercialization we combine revealed preference rp data on adoption of bt cotton varieties with stated preference sp data on willingness to adopt to estimate demand using a double bounded maximum likelihood procedure using estimated demand equations we simulate the costs of reducing conventional insecticide applications through subsidization of bt cotton results indicate that reducing cotton insecticide applications by 40 in the southeast would require a 21 acre subsidy with total annual program costs between 53 million and 60 million

policy evaluation with combined actual and contingent response data the city of marietta georgia experimentally switched from flat fee financing to volume based pricing for its trash services in january 1994 both before and during the experiment detailed data on individuals observed responses to the actual introduction and contingent behavioral responses to a hypothetical introduction of volume based pricing were collected this study applies these data and investigates the methodology of collecting contingent behavior data and their use in policy analysis in particular this study empirically evaluates the effect of experience with the policy on responses to contingent behavior questions and tests for potential bias in the contingent behavior data

combining revealed and stated preference methods to value environmental amenities at residential locations this paper combines an established revealed preference method discrete choice he donic analysis and a relatively new stated refer ence method choice based conjoint analysis in order to estimate more accurately the aesthetic benefits generated by the presence and quality of environmental amenities associated with residen tial locations it applies the combined approach to the housing market of fairfield connecticut which contains several environmental amenities and is experiencing an improvement in the quality of its coastal wetlands due to active restoration efforts jel q26

is meta analysis a noah s ark for non market valuation this paper describes meta analytical methods as they have been applied to non market valuation research these studies have been used to review and synthesize literature and more recently in benefit transfer this second use imposes a higher standard on the consistency in economic concepts being summarized and in the resources included in a meta analysis to meet this need the paper proposes and illustrates a structural framework using a generalized method of moments estimator to estimate the parameters of a preference function with the benefits estimates usually encountered in meta analytic summaries

a semi parametric estimator for revealed and stated preference data an application to recreational beach visitation abstract we present a semi parametric approach for jointly estimating revealed and stated preference recreation demand models the discrete factor method dfm allows for correlation across demand equations and incorporates unobserved heterogeneity our model is a generalized negative binomial with random effects the random effect is composed of a discrete representation of unobserved heterogeneity and a factor loading that translates the heterogeneity measure into a demand effect our empirical application is to beach recreation demand in north carolina statistical evidence supports our dfm specification which imposes less restriction on model dispersion and incorporates unobserved heterogeneity in a flexible manner elasticity estimates are smaller than those derived from models with parametric specifications for unobserved heterogeneity and welfare estimates are slightly larger and less precise while parametric models clearly dominate if the specification of unobserved heterogeneity is correct the semi parametric dfm provides a flexible alternative in cases where mis specification is a potential problem

convergent validity and the time consistency of preferences evidence from the iowa lakes recreation demand project we examine the consistency of preferences over time and as implied by revealed versus stated preference contingent behavior data studies in this area are typically based upon a single site and focus on consumer response to changes in travel cost or site access we use data from the iowa lakes project which provides information on usage patterns over several years and for 132 lakes along with detailed water quality data this allows us to test for convergence in how individuals respond to changing site characteristics as well as the consistency of preferences over time and between actual versus contingent trips

evaluation of nonmarket goods recovering unconditional preferences a new approach is proposed for the evaluation of nonmarket goods starting from a complete or incomplete conditional demand system for market goods which is observable and depends on nonmarket goods this information is not sufficient to recover the underlying preference ordering of the representative consumer the central idea is to employ additional marginal willingness to pay functions for the nonmarket goods since they can be estimated either together with the demand system or in a separate step they are less arbitrary than the assumptions or hypotheses usually made if the entire system is weakly integrable the underlying ordering and appropriate welfare measures can be derived in this article i investigate the relationship between conditional and unconditional demand systems present sufficient conditions for weak integrability and demonstrate the practicability of the procedure proposed by means of three examples

a new paradigm for valuing non market goods using referendum data maximum likelihood estimation by censored logistic regression abstract this paper challenges the w m hanemann amer j agr econom 66 332 341 1984 and c sellar j p chavas and j r stoll j environ econom management 13 382 390 1986 utilizations of logit models to estimate the value of non market resources from referendum survey data these data are more informative than conventional choice data the random utility interpretation of logit models is therefore too restrictive bypassing the utility function entirely it will be shown that parameters and standard errors for utility theoretic inverse hicksian demand functions can be extracted directly and much more simply estimated demand functions need not be limited to those corresponding to the linear in parameters utility difference specifications which can be handled by packaged logit programs

improving environmental valuation estimates through consistent use of revealed and stated preference information abstract environmental valuation data from stated and revealed preference methods are integrated into a unified model of preferences for environmental quality improvement that identifies the use and nonuse components of the total value estimate this articulates clearly what parts of the total value estimate come from each type of data and permits tests of whether estimated preferences satisfy weak complementarity between the environmental good of interest and related private goods the statistical advantages of using more information for the valuation problem are exploited while retaining flexibility to identify value estimates from any individual method of analysis

quantifying the severity of fuel poverty its relationship with poor housing and reasons for non investment in energy saving measures in ireland fuel poverty has generally been calculated by quantifying the number of households spending in excess of 10 of income on home heating this definition has a number of significant practical and scientific limitations this paper employs self reported data to calculate the severity of fuel poverty in ireland to identify chronic fuel poor households from occasional sufferers it also assesses domestic energy efficiency levels ireland is a useful case study as it demonstrates the highest variations in seasonal mortality and morbidity in northern europe both of which are associated with fuel poverty ireland is also experiencing extreme difficulties meeting its environmental emissions targets in light of recent spectacular economic growth reducing fuel poverty would lower energy related emissions assisting policy makers achieve these challenging targets furthermore little empirical research has been undertaken on fuel poverty in ireland this paper identifies key social groups at risk by conducting detailed socio economic and socio demographic analyses the relationship between fuel poverty and adverse housing conditions damp condensation is also examined moreover the reasons behind householders not investing in energy saving measures are reported the results show that ireland suffers from similar levels of fuel poverty as the uk with low income households suffering the greatest the key policy implications are outlined

combining revealed preference data with stated preference data a latent class approach a substantial literature exists combining data from revealed preference rp and stated preference sp sources aimed either at testing for the convergent validity of the two approaches used in nonmarket valuation or as a means of drawing on their relative strengths to improve the ultimate estimates of value in doing so it is assumed that convergence of the two elicitation approaches is an all or nothing proposition i e the rp and sp data are either consistent with each other or they are not the purpose of this paper is to propose an alternative framework that allows for possible divergence among individuals in terms the consistency between their rp and sp responses in particular we suggest the use of a latent class approach to segment the population into two groups the first group has rp and sp responses that are internally consistent while the remaining group exhibits some form of inconsistent preferences an em algorithm is employed in an empirical application that draws on the alberta and saskatchewan moose hunting data sets used in earlier combined rp and sp exercises the empirical results suggest that somewhere between one third and one half the sample exhibits consistent preferences we also examine differences in welfare estimates drawn from the two classes

another theorem on using market demands to determine willingness to pay for non traded goods abstract this paper contains a proof of the following theorem let e1 and e1 denote an agent s expenditures on two groups of goods which are substitutes and complements to a non traded good suppose that both the agent s income and the quantity of the non traded good provided him have a positive effect on these two amounts then these effects can be used to place upper and lower bounds on the agent s marginal willingness to pay for the non traded good

spring cleaning rural water impacts valuation and property rights institutions the brief summarizes the spring cleaning rural water impacts valuation and property rights institutions the first two rounds of spring protection occurred in january april 2005 and august november 2005 the author measure health impacts of spring protection an investment that improves source water quality the author also estimate households valuation of spring protection and simulate the welfare impacts of alternatives to the current system of common property rights in water which limits incentives for private investment spring infrastructure investments reduce fecal contamination by 66 percent but household water quality improves less due to recontamination child diarrhea falls by one quarter travel cost based revealed preference estimates of households valuations are much smaller than both stated preference valuations and health planners valuations and are consistent with models in which the demand for health is highly income elastic the author estimate that private property norms would generate little additional investment while imposing large static costs due to above marginal cost pricing private property will function better at higher income levels or underwater scarcity and alternative institutions could yield pareto improvements

conditional choice probability estimation of dynamic discrete choice models with unobserved heterogeneity we adapt the expectation maximization algorithm to incorporate unobserved heterogeneity into conditional choice probability ccp estimators of dynamic discrete choice problems the unobserved heterogeneity can be time invariant or follow a markov chain by developing a class of problems where the difference in future value terms depends on a few conditional choice probabilities we extend the class of dynamic optimization problems where ccp estimators provide a computationally cheap alternative to full solution methods monte carlo results confirm that our algorithms perform quite well both in terms of computational time and in the precision of the parameter estimates

specification tests for mixed demand systems with an emphasis on combining contingent valuation and revealed data abstract in a world characterized by r unrationed goods i e market goods and n r rationed goods such as most environmental goods necessary and sufficient conditions for the existence of an underlying rational preference structure are derived based on a system of mixed demand functions with complete information with incomplete information the case of a partial demand system is addressed and a test for separability is proposed the implications for testing rationality in a world characterized by combined rp and sp individual data are examined for data consistency testable conditions are derived

combining revealed and stated data to examine housing decisions using discrete choice analysis abstract this paper uses stated preference and revealed preference data separately and jointly to examine individuals housing choices in particular it combines an established revealed preference approach discrete choice analysis of actual housing purchases and a relatively new stated preference approach choice based conjoint analysis of hypothetical housing purchases to provide us with a better understanding of the factors driving housing decisions these methods are appropriately combined since they reflect the same decision process households select the dwelling that provides the best combination of attributes from the feasible set of alternatives in total this paper analyzes three data sets only actual housing purchases only hypothetical housing purchases and both types of purchases combined analysis finds that actual and hypothetical housing purchases are similar decision processes with respect to some attributes yet are dissimilar with respect to other attributes nevertheless combining the two types of data improves identification of both categories of attributes journal of economic literature classification number r21

attitudes and behaviours of private sector landlords towards the energy efficiency of tenanted homes abstract the uk s housing stock generates approximately 27 of the country s total annual carbon emissions in light of the legally binding targets to reduce carbon emissions new housing is subject to a tightening of regulations governing energy demand and efficiency resulting in a gradual improvement in carbon emissions the question is how to achieve the deep carbon emission reductions from existing domestic properties of which 75 will still be in use in 2050 government has sought to provide incentives to homeowners to improve the energy efficiency of their households and mandate improvements in socially rented housing using a range of fiscal measures most recently the green deal there has however been little consideration of the 18 of uk households who privately rent their home a tenure that is growing fast the aim of this research is to investigate the factors that influence private sector landlords when considering energy efficiency improvements to their tenanted homes the results indicate that government policy has consistently failed to engage private sector landlords in the issue of energy efficiency and thus measures must be taken to understand the motivations of landlords in order to design effective incentives and interventions

time is money improved valuation of time and transportation costs the proper valuation of time isimportant for estimating the demand for severaleconomic goods this paper explores the propervaluation of time when estimating recreationaldemand where time costs represent asubstantial portion of the purchase price toestimate demand this paper uses a travel costframework to analyze actual behavior revealedpreference data and hypothetical behavior stated preference data which is induced byhypothetical increases in access fees traveltime and travel distance by comparing theresponses to these three contingencies theanalysis adjusts and improves the valuation oftime costs as evidence of this improvement this analysis demonstrates a great increase inthe consistency between the revealed and stateddata similarly this paper improves thevaluation of transportation related costs

accounting for stochastic shadow values of time in discrete choice recreation demand models abstract in this paper a discrete choice recreation demand model that explicitly accounts for a stochastic shadow value of time function is proposed using data from a survey of san diego beach users the stochastic shadow value of time labor supply and beach choice are jointly estimated results from this joint estimation approach are compared with the familiar two step approach that estimates labor supply first and uses predicted values of time in the recreational site choice model the approaches produce markedly different welfare measures with the two step model which does not account for unobserved variability of time values predicting significantly higher values a monte carlo simulation illustrates how ignoring the stochastic nature of shadow value of time in discrete choice recreation demand models can bias model parameters and hence welfare estimates

weak complementarity path independence and the intuition of the willig condition abstract weak complementarity is usually invoked for valuing public goods using information on private goods however using uncompensated demands requires a second condition the willig condition this paper present an intuitive explanation of the willig condition and shows that the alternative versions are equivalent to a path independence condition for line integrals this condition is fulfilled for compensated demands but not uncompensated demands except in restrictive special cases it is shown that this is a type of quasi homotheticity and requires that the income flexibility of quality must equal the income elasticity of the weak complement the importance and restrictiveness of the willig condition are shown using three alternative functional forms

energy poor or fuel poor what are the differences abstract energy poverty and fuel poverty are descriptors of problems of households energy consumption they are both distinct problems and have been addressed by many researchers organizations and governments cross use of the terms of energy poverty and fuel poverty in published papers is common as an accurate descriptor is the presupposition of research and policy development especially for those who just started to pay attention to this issue this paper compares the definitions research priorities status quo and problems of these two concepts and summarizes the relationship between them the paper suggests that only when the research targets are households who are living in a cold climate and have difficulty in getting access to electricity or modern cooking facilities and in supplying indoor heating with appropriate cost the concepts of energy poverty and fuel poverty have the chance to be broadened and mutually integrated

dynamic product positioning in differentiated product markets the effect of fees for musical performance rights on the commercial radio industry this article predicts how radio station formats would change if as was recently proposed music stations were made to pay fees for musical performance rights it does so by estimating and solving using parametric approximations to firms value functions a dynamic model that captures important features of the industry such as vertical and horizontal product differentiation demographic variation in programming tastes and multi station ownership the estimated model predicts that high fees would cause the number of music stations to fall significantly and quite quickly for example a fee equal to 10 of revenues would cause a 4 6 drop in the number of music stations within 2 1 2 years and a 9 4 drop in the long run the size of the change is limited however by the fact that many listeners particularly in demographics that are valued by advertisers have strong preferences for music programming publication abstract

structural benefit transfer an example using vsl estimates abstract this paper describes and illustrates a method for benefits transfer referred to as preference calibration or structural benefits transfer this approach requires selection of a preference model capable of describing individual choices over a set of market and associated non market goods to maximize utility when facing budget constraints once the structure is selected the next step involves defining the analytical expressions for the tradeoffs being represented by the set of available benefit measures these algebraic relationships are used with the benefit estimates from the literature to calibrate the parameters of the model the calibrated model then offers the basis for defining the new tradeoffs required for the policy analysis i e for transferring benefits a new application is used to illustrate the structural benefits transfer logic it involves the benefits for mortality risk reductions measured with labor market compensation a worker would accept to be willing to work with added risk the measure is usually labeled the value of a statistical life vsl our application indicates that we should not have expected differences in these measures for the economic value of risk reductions with age the calibrated estimates were not greatly different for combinations of risk levels labor supply choices wages and non wage income for older adults thus simple adjustments relying on value per discounted life year remaining seem questionable

combining revealed and stated preference data to estimate preferences for residential amenities a gmm approach we show how stated preference information obtained from a choice experiment and revealed preference information based on housing market transactions can be combined via generalized method of moments gmm estimation specifically we use a moment condition matching the predicted marginal willingness to pay wtp from a first stage hedonic model to the marginal wtp formula implied by the choice experiment utility function this is coupled with other moments from the choice experiment to produce gmm based estimates of parameters that reflect the strengths of each data source our application values remediation of a contaminated site in buffalo new york and we find evidence in support of estimates arising from our approach jel q51 q53

the effect of medicaid abortion funding restrictions on abortions pregnancies and births this paper considers whether state medicaid abortion funding restrictions affect the likelihood of getting pregnant having an abortion and bearing a child we exploit a natural experiment afforded by supreme court decisions and employ more traditional multivariate models with alternative fixed effect specifications an analysis of 12 years of state level data indicate that restrictions are associated with a reduction in abortions and either no change or a reduction in births implying fewer pregnancies subsequent analysis of the national longitudinal survey of youth nlsy is consistent with these findings and show the response is concentrated among the low income population

models for referendum data the structure of discrete choice models for contingent valuation abstract in 1979 bishop and heberlein introduced an appealing variant of the contingent valuation method which required only yes or no responses hanemann developed a utility theoretic interpretation of the yes no responses which has helped popularize the approach recently cameron has offered another interpretation also utility theoretic which she argues is more general than the hanemann random utility model this paper compares the deterministic models suggested by hanemann and cameron showing them to be dual to each other it shows that correct specification of either function must exclude endogenous variables such as quantity demanded it also demonstrates that using utility theoretic models allows one to compare travel cost models and contigent valuation models on the basis of their implied behavior not on the unobservable surplus or variation measure

empirical strategies for incorporating weak complementarity into consumer demand models abstract this article appraises existing empirical strategies for incorporating weak complementarity into consumer demand models the repackaging integrating back and discontinuity approaches are evaluated in terms of their behavioral implications and potential usefulness for applied research the appraisal suggests that the repackaging approach offers the most flexibility and tractability in the multi good demand system framework but the integrating back approach holds considerable promise in the single good context a multi good empirical comparison suggests that qualitatively similar policy inference arises from different repackaging approaches

the dual structure of incomplete demand systems integrability of incomplete demand systems is discussed the concepts of weak integrability quasi expenditure function quasi indirect utility function and quasi utility function are defined their relationships to the expenditure function indirect utility function and utility function are developed the dual structure of the quasi functions permits exact welfare analysis and reveals the conditional preference structure for the commodities of interest new results relating the uniqueness and exactness of consumer s surplus to the structure of the expenditure and indirect utility functions are obtained

modeling discrete choices with augmented perception hurdles through creating latent perception hurdles associated with each attribute considered in a stated conjoint experiment this article describes a model that augments the conventional approach by utilizing the importance ratings provided by respondents prior to the discrete choice stage the resulting perception hurdle logit phl model has both advantages and disadvantages compared to the conditional logit cl and mixed logit models although the proposed model may not have the best within sample fit it outperforms the other two models in predicting choices in a hold out sample in addition the proposed model is also used to reveal that depending on their own characteristics and the process of the survey respondents may employ an array of different decision strategies

combining revealed and stated preferences consistency tests and their interpretations this article models the recreation demand for iowa wetlands combining survey data on both actual usage patterns i e revealed preferences rps and anticipated changes to those patterns under hypothetical increases in trip costs i e stated preferences sps we formulate and test specific hypotheses concerning potential sources of bias in each approach and discuss what can be learned about the validity of the models from such tests

measuring market power in the ready to eat cereal industry the ready to eat cereal industry is characterized by high concentration high price cost margins large advertising to sales ratios and numerous introductions of new products previous researchers have concluded that the ready to eat cereal industry is a classic example of an industry with nearly collusive pricing behavior and intense nonprice competition this paper empirically examines this conclusion in particular i estimate price cost margins but more importantly i am able empirically to separate these margins into three sources i that which is due to product differentiation ii that which is due to multi product firm pricing and iii that due to potential price collusion the results suggest that given the demand for different brands of cereal the first two effects explain most of the observed price cost margins i conclude that prices in the industry are consistent with noncollusive pricing behavior despite the high price cost margins leading firms are able to maintain a portfolio of differentiated products and influence the perceived product quality it is these two factors that lead to high price cost margins

estimation of dynamic discrete choice models in continuous time with an application to retail competition this paper provides a method for estimating and solving dynamic discrete choice models in a continuous time framework that is computationally light the method is particularly useful in dynamic games in the proposed framework players face a standard dynamic discrete choice problem at decision times that occur stochastically the resulting stochastic sequential structure naturally admits the use of ccp methods for estimation and makes it possible to compute counterfactual simulations for relatively high dimensional games we apply our techniques to examine the impact of walmart s entry into the retail grocery industry showing that even the threat of entry by walmart has a substantial eect on market structure

information and bargaining in markets for environmental quality this paper explores the role of information on residential real estate prices housing transactions from 1990 formed the sample frame for surveying home buyers on their knowledge of local environmental disamenities both at the time their homes were purchased and when the survey was conducted of particular interest was home buyers knowledge of nearby landfill sites because of clustering of survey responses a sample selection model that combines transaction data with 1990 census micro data was used the results suggest that home buyers are poorly informed about disamenities and that those who are informed bid down the price of a home

definitions of fuel poverty implications for policy abstract this paper outlines why the definition of fuel poverty is important in policy formulation and describes how the government s current definitions evolved from the original concept it discusses the determination of income and fuel costs and the possibilities for a relative and common european measure it examines problems inherent in assessing fuel costs as a percentage of income and puts forward the arguments for a budget standard approach the paper illustrates how the size of the problem depends on the definition and chosen threshold and suggests advantages for a rating scale it illustrates how the income composition and thresholds also govern the distribution of the target populations and the relative importance of the main causal factors and examines the consequent policy implications it explores the definition of vulnerable households and the importance of severity and questions whether the uk fuel poverty strategy is targeted at households least able to afford their fuel costs as the name implies or primarily those at risk from excess winter and summer mortality and morbidity finally after examining the role of supplementary indicators it looks at the opportunities for changing the definition and comments on the government review of the definition and targets

consistency in mixed demand systems contingent valuation and travel cost data in contrast to previous literature we propose a consistency test that does not impose any particular common functional form for the preference structure underlying the travel cost tc and contingent valuation cv models we derive testable consistency conditions between tc and cv data in the context of mixed demand systems when valuing changes in environmental quality these conditions are a subset of the rationality conditions the proposed consistency tests are implemented combining tc and cv data the empirical results show that it is possible to combine stated tc and cv but not revealed tc and cv data

willingness to pay for quality improvements should revealed and stated preference data be combined abstract in this article we propose theoretically consistent welfare measurement of use and nonuse values for an improvement in environmental quality with revealed and stated preference data an analytical model based on the comparative static analysis of the variation function that describes the relationship between recreation demand and dichotomous choice contingent valuation models is estimated our results show that revealed and stated data should not be combined under the same assumed preference structure unless the two decisions imply the same change in behavior induced by the quality change in addition our results indicate scope effects in willingness to pay measures estimated with stated preference data

the impact of state abortion restrictions on minors demand for abortions this study uses a weighted least squares model and a fixed effects model to estimate the impact of parental consent laws and laws governing medicaid funding of abortions on the adolescents demand for abortion in the united states during 1978 90 the focus is on adolescent pregnancy because 12 of total legal abortions in 1987 were to adolescents aged under 18 years the rate of abortion and types of abortion law range widely between states data are obtained from the us center for disease control on reported abortions from the naral foundation on the dates of actual enforcement restrictions and from the alan guttmacher institute on abortion providers the empirical model is based on a model developed by grossman and joyce proxy measures are used to represent abortion sentiment fixed effects models indicated that there was a decline of 13 17 in adolescents demand for abortion in states with enforced parental involvement laws compared to states without enforced laws the results implied a 9 15 decline in adolescents demand for abortion in states that restricted medicaid funding of abortion compared to states that did not there was a positive association between abortion demand and income and between abortion demand and the availability of abortion providers the inclusion of the abortion sentiment proxies did not change the signs and magnitudes of the impact very much in the fixed effects models it is posited that the negative impacts of abortion restrictions on adolescent abortion demand cannot be attributed to unobserved heterogeneity four methods of modeling are used to account for the potential role of unobserved heterogeneity

averting behavior in the presence of public spillovers household control of nuisance pests this paper empirically imple ments an averting behavior model for gypsy moth control explicitly recognizing the joint pri vate and public spillover motivations for con trol the results demonstrate that averting be havior models can capture complex behavioral influences suggesting that such models can be extended beyond health related applications the model yields a reduced form parameter which cannot be identified using actual behavior data alone a method combining models of ac tual behavior and contingent behavior is piro posed as a way to directly measure the produc tion and preference effects jel q23

combining contingent valuation and travel cost data for the valuation of non market goods the travel cost method tcm has long been used to infer the economic value of nonmarket resources and public goods more recently contingent valuation cvm survey methods have gained popularity for eliciting these values here cvm survey responses are combined with tcm data on actual market behavior to estimate jointly both the parameters of the underlying utility function and its corresponding ordinary demand function this is a prototypical empirical example of a new modeling strategy variants of which should prove useful in many applications especially where reliance on a single valuation method is undesirable

discrete choice survey experiments a comparison using flexible methods abstract this study investigates the convergent validity of discrete choice contingent valuation cv and contingent rating ranking cr methods using flexible econometric methods our results suggest that cv and cr can produce consistent data achieve convergent validity when respondent s preferred choices and the same changes in environmental quality are considered we also find that cr models that go beyond modeling the preferred choice and include additional ranks cannot be pooled with the cv models accounting for preference heterogeneity via random coefficient models and their flexible structure does not make rejection of the hypothesis of convergent validity less likely but instead rejects the hypothesis to about the same degree or perhaps more frequently than fixed parameter models commonly used in the literature

regulation and the optimal size and type of abortion provider between 1973 the year the supreme court ruled in roe v wade that women have the right to decide whether or not to terminate their pregnancies and 1982 the number of abortion providers increased by 81 per cent however between 1982 and 1992 a period of increasing state level abortion regulation the number of abortion providers decreased by 18 per cent we know very little about the factors that influence the willingness and ability of hospitals clinics and physicians to provide abortion services over time based on state data from 1978 to 1992 the results of this paper suggest that large abortion providers are better able to compete and survive in the market also clinics and physicians offices appear to be gaining market share relative to hospitals further this paper includes analysis of the impact of state level medicaid funding regulations on the number size and type of abortion provider these results have important implications for women s access to abortion services and thus have impor

computable markov perfect industry dynamics we provide a general model of dynamic competition in an oligopolistic industry with investment entry andexit toensurethatthereexistsacomputationallytractablemarkov perfectequilibrium we introduce firm heterogeneity in the form of randomly drawn privately known scrap values and setup costs into the model our game of incomplete information always has an equilibrium in cutoff entry exit strategies in contrast the existence of an equilibrium in the ericson and pakes model of industry dynamics requires admissibility of mixed entry exit strategies contrary to the assertion in their article that existing algorithms cannot cope with in addition we provide a condition on the model s primitives that ensures that the equilibrium is in pure investment strategies building on this basic existence result we first show that a symmetric equilibrium exists under appropriate assumptions on the model s primitives second we show that as the distribution of the random scrap values setup costs becomes degenerate equilibria in cutoff entry exit strategies converge to equilibria in mixed entry exit strategies of the game of complete information

estimating the private benefits of vaccination against cholera in beira mozambique a travel cost approach abstract this paper reports the results of the first study that estimates households private demand for cholera vaccines using the travel cost method we take advantage of an unusual natural experiment in january 2004 more than 41 000 residents from various locations in beira mozambique received two doses of oral cholera vaccine free of charge during the first vaccination trial to test its effectiveness in an endemic cholera zone of africa about 30 000 people participated from outside the target zone resulting in long queues and an average waiting time of about 85 min per dose we estimated travel cost models of the revealed demand for cholera vaccines among households informed of the trial using information collected in in person interviews conducted during the summer of 2005 to explore households participation in the trial we used standard and zero inflated household count models for all household members and dichotomous choice models for the head of the household our analysis shows that the quantity of vaccines obtained by households and the likelihood of participation decreased as travel cost in time and transport expenses rose our best estimates of per capita willingness to pay for the two required doses of cholera vaccine are about 0 85 usd these estimates are sensitive to the assumed value of time spent acquiring vaccines

augmenting travel cost models with contingent behavior data this paper proposes contingent behavior survey questions as a valuable supplement to observed data in travel cost models of non market demand for recreational resources a set of observed and contingent behavior results for each survey respondent allows the researcher to control for individual heterogeneity by taking advantage of panel data methods when exploring the nature of respondent demands the contingent scenarios also provide opportunities to a test for differences between observed and contingent preferences and or b assess likely demands under conditionsbeyond the domain of observed variation in costs or resource attributes most importantly contingent scenarios allow the researcher to imposeexogenously varying travel costs exogenous imposition of travel costs together with panel methods reduces the omitted variables bias that plagues observed data travel cost models of recreational demand using a convenience sample of data for illustrative purposes we show how to estimate the demand for recreational angling by combining observed and contingent behavior data we begin with simple naive pooled poisson models and progress to more theoretically appropriate fixed effects panel poisson specifications

coping with low incomes and cold homes abstract this paper presents findings from a study of low income households in great britain which explored households strategies for coping both with limited financial resources in the winter months when demand for domestic energy increases and in some cases with cold homes the study combined a national survey of 699 households with an income below 60 per cent of national median income with in depth interviews with a subsample of 50 households the primary strategy adopted by low income households to cope with financial constraint was to reduce spending including spending on essentials such as food and fuel and thereby keep up with core financial commitments while spending on food was usually reduced by cutting the range and quality of food purchased spending on energy was usually reduced by cutting consumption sixty three per cent of low income households had cut their energy consumption in the previous winter and 47 per cent had experienced cold homes improvements to the thermal performance of homes reduced but did not eliminate the risk of going cold as any heating cost could be a burden to households on the lowest incomes householders attitudes were central to their coping strategies with most expressing a determination to get by come what may

a joint latent class model combining likert scale preference statements with choice data to harvest preference heterogeneity in addition to choice questions revealed and stated choices preference surveys typically include other questions that provide information about preferences preference statement data include questions on the importance of different attributes of a good or the extent of agreement with a particular statement the intent of this paper is to model and jointly estimate preference heterogeneity using stated preference choice data and preference statement data the starting point for this analysis is the belief that the individual has preferences and both his her choices and preference statements are manifestations of those preferences our modeling contribution is linking the choice data and preference statement data in a latent class framework estimation is straightforward using the e m algorithm even though our model has hundreds of preference parameters our estimates demonstrate that 1 within a preference class the importance anglers associate with different green bay site characteristics is in accordance with their responses to the preference statements 2 estimated across class utility parameters for fishing green bay are affected by the preference statement data 3 estimated across class preference statement response probabilities are affected by the inclusion of the choice data and 4 both data sets influence the number of classes and the probability of belonging to a class as a function of the individual s type

incorporating generalized marginal budget shares in a mixed demand system this article extends a rotterdam type of mixed demand system by replacing its constant marginal budget shares with the ones derived from originally defined and specified mixed engel curves that take a generalized functional form using the box cox transformation an empirical illustration is given for japanese demand for fresh and processed fruits and vegetables the results show that the rotterdam parameterization of marginal budget shares which corresponds to those in linear mixed engel curves is preferred by the data and that improper assumptions of the form of mixed engel curves underlying a mixed demand system can bias its elasticities

regulation imperfect competition and the u s abortion market the u s abortion market has grown increasingly concentrated recently while many states tightened abortion laws using data on abortion providers i estimate an equilibrium model of demand price competition entry and exit to capture the effect of regulation on industry dynamics estimates show regulations played an important role in determining the abortion market structure and evolution counterfactual simulations reveal increases in demand aimed regulation were the most important observed factor in explaining recent abortion declines simulating utah s regulatory regime nationally shows tightening abortion restrictions can increase abortions in equilibrium mainly through tilting the competitive landscape toward low price providers

construct validity of dichotomous and polychotomous choice contingent valuation questions in this note we conduct construct validity tests for dichotomous choice dc and polychotomous choice pc contingent valuation questions contrary to previous results we find that dc and pc estimates of willingness to pay are theoretically valid convergent valid and similar in terms of statistical precision similar to previous results pc respondents are less sensitive to information than dc respondents we conclude that dc and pc valuation questions are construct valid for this study sequential pc valuation questions could be used in studies where obtaining information about the certainty or intensity of respondent preferences would be useful