Scholars' Bank :: Browsing by Author "Cameron, Trudy Ann"

Browsing by Author "Cameron, Trudy Ann"

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Open Access
Appendices to Superfund Taint and Neighborhood Change: Ethnicity, Age Distributions, and Household Structure
(University of Oregon, Dept. of Economics, 2003-12) Cameron, Trudy Ann; Crawford, Graham D.
Certain sociodemographic groups often seem to be relatively more concentrated near environmental hazards than in the surrounding community. It is well-known that snapshot cross-sectional statistical analyses cannot reveal how residential mobility for these different groups reacts to changing public perceptions of environmental hazards. Decennial panel data over four census periods, for census tracts surrounding seven different urban Superfund localities, allow us to examine how ethnicities, the age distribution and family structure vary over time with distance from these major environmental disamenities. If the slope of the distance profile decreases over time, the group in question could be argued to be “coming to the nuisance.” We find a lot of statistically significant movement, including some evidence of minority move-in and increasing relative exposure of children, especially those in singleparent households. However, it appears to be hard to make generalizations, across localities, about the mobility patterns for different groups. This heterogeneity may account for the difficulty other researchers have experienced in identifying systematic effects in data that are pooled across different environmental hazards. Changes over time in the sociodemographic mix near Superfund sites may also help explain differences in the extent to which housing prices rebound after cleanup commences.
Open Access
Consumer Willingness to Pay for Transitional Organic Produce
(University of Oregon, 2013-10-03) Williams, Marissa; Cameron, Trudy Ann
United States agriculture is continuing to shift toward organic production techniques to align with consumer demand, yet organic products make up an insignificant portion of the food market. This disparity has been examined via consumer willingness to pay for organic products and research on the costs and benefits of organic operations; however, little has been investigated about a potential transitional organic market. In shifting from conventional to organic agriculture there is a substantial transition phase of at least three years, during which producers cannot label their products as USDA organic. This research therefore examines consumer willingness to pay for transitional organic produce based on a Lane County representative adult population (n = 200). Results of the conjoint choice stated preference survey suggest that there exists a viable market for transitional organic products, revealing systematic heterogeneity in preferences for produce labeled as transitional USDA organic.
Open Access
Differential Attention to Attributes in Utility-theoretic Choice Models
(University of Oregon, Dept of Economics, 2008-10) Cameron, Trudy Ann; DeShazo, J. R.
We show in a theoretical model that benefits of allocating additional attention to evaluating the marginal attribute with in choice set depend upon the expected utility loss from making a suboptimal choice as a result of ignoring that incremental attribute. Guided by this analysis, we then develop a very general and practical empirical method for measuring the individual's propensity to attend to attributes. As a proof of concept, we offer an empirical example of our method using a conjoint analysis of demand for programs to reduce health risks. Our results suggest that respondents differentially allocate attention across attributes, as a function of the mix of attribute levels in a choice set. This behavior can cause researchers who fail to model attention allocation to incorrectly estimate the marginal utilities derived from selected attributes. This illustrative example is a first attempt to implement an attention-corrected choice model with a sample of field data from a conjoint choice experiment.
Open Access
Directional Heterogeneity in Distance Profiles in Hedonic Property Value Models
(University of Oregon, Dept. of Economics, 2003-07-01) Cameron, Trudy Ann
Failure to allow for directional heterogeneity can obscure otherwise statistically significant distance effects in hedonic property value models. If ambient pollution data are unavailable, researchers often rely upon distance from a point source of pollution as a proxy for ambient environmental quality. However, damages from all types of point-source disamenities may exhibit directional heterogeneity. We generalize conventional distance models to allow for directional effects and show that commonly used linear and quadratic spatial trend variables capture directional heterogeneity in a manner that has not previously been recognized. Appropriate spatial models can also inform the social planner’s problem of optimal allocation of source reduction across polluters. When independently calibrated tranport functions are not available, individual properties can be viewed as ambient receptor sites. Hedonic models can yield estimates of the product of marginal social damages from ambient concentrations and the change in ambient concentration per unit of emissions from each source. Optimal emissions depend upon the spatial distribution of all affected properties relative to each source, the parameters of the hedonic model, and marginal abatement costs.
Open Access
Effects of Behavioral and Environmental Factors on Infant Health
(University of Oregon, 2015-08-18) Cil, Gulcan; Cameron, Trudy Ann
Health at birth is considered an important indicator of health outcomes in adulthood. It is also shown to have a strong association with future educational attainment and labor market outcomes. I examine the effects of behavioral and environmental factors on infant health. The factors I focus on include alcohol consumption during pregnancy, extreme weather events associated with climate change, and pollution that may result from unconventional oil and natural gas development. In Chapter II, I examine the effects of point-of-sale alcohol warning signage that alcohol retailers are required to post in some states on alcohol use during pregnancy and on birth outcomes. I find that point-of-sale warning signs discourage alcohol consumption among pregnant women and are associated with a decrease in the odds of newborns having very low birth weight or being very pre-term. The findings of this research inform decision makers about a potentially effective mechanism through which alcohol consumption among pregnant women can be reduced. They also suggest causal evidence for the link between prenatal alcohol exposure and inferior health at birth. Chapter III documents that exposure to heat waves during pregnancy is associated with increased likelihood of the mother experiencing an adverse health condition during pregnancy and the newborn having an abnormal condition at birth. The results provide an assessment of the magnitude and timing of the effects of extreme heat events associated with climate change on infant health which is potentially helpful in enhancing the effectiveness of adaptation efforts. Finally, Chapter IV provides an empirical investigation of the link between unconventional oil and natural gas development and infant health. The results indicate that unconventional drilling activity is associated with a small, but statistically significant, decline in birth outcomes, especially for those living in rural areas. Given that it is estimated that the rapid expansion in unconventional oil and gas extraction will continue for at least a few more decades, the results of this study may contribute to the discussions related to initiation or tightening of regulations and monitoring efforts to control pollution. This dissertation includes previously unpublished co-authored material.
Open Access
Eliciting Individual-Specific Discount Rates
(University of Oregon, Dept. of Economics, 2003-01-01) Cameron, Trudy Ann; Gerdes, Geoffrey R.
Longstanding debate over the appropriate social discount rate for public projects stems from our lack of knowledge about how individual discount rates vary across people and across choice contexts. Using a sample of roughly 15,000 choices by over 2000 individuals, we estimate utility theoretic models concerning private tradeoffs involving money over time that reveal individual specific discount rates. We control for experimentally differentiated choice scenarios, sociodemographic heterogeneity, and elicitation formats, and complex forms of heteroscedasticity. Statistically significant heterogeneity in discount rates is quantified for both an exponential discounting model and a competing hyperbolic model, but neither specification clearly dominates.
Open Access
An Empirical Model of Demand for Future Health States when Valuing Risk-Mitigating Programs
(University of Oregon, Dept. of Economics, 2004-03) Cameron, Trudy Ann; DeShazo, J. R.
We develop a structural option price model in which individuals choose among competing risk-mitigating programs to alter their probability of experiencing future years in various degraded health states. The novel aspects of this model include separate estimates of the marginal utilities of avoiding years of morbidity and lost life-years. With these marginal utilities, we may evaluate a broad spectrum of probabilistic health outcomes over any period of an individual’s future life. The model also reduces potential biases associated with singleperiod, single-risk models typically used to produce estimates of the Value of a Statistical Life (VSL) by allowing individuals to substitute risk mitigation across competing sources of risk and across future years of their lives. We evaluate this model using data from a national survey that contains a choice experiment on demand for the mitigation of illness-specific risks.
Open Access
Essays in Environmental and Public Economics
(University of Oregon, 2012) Vander Naald, Brian; Vander Naald, Brian; Cameron, Trudy Ann
Benefit-cost analysis of environmental policies typically focuses on benefits to human health and well-being. When it comes to humans' willingness to pay (WTP) for improvements in the quality of life for other species, however, the evidence is limited. We argue that the other-species morbidity-reduction component of WTP should be calculated net of any "outrage" component associated with the cause of the harm. This net WTP is likely to be correlated with the premium that people are willing to pay for chicken products from birds for which the quality of life has been enhanced by improved animal welfare measures. This paper uses a conjoint choice stated preference survey to reveal the nature of systematic heterogeneity in preferences for "humanely raised" versus "conventionally raised" chicken. We also use latent class analysis to distinguish between two classes of people - those who are willing to pay a premium for humanely raised chicken and those who are not. Proposition 21 on California's 2010 ballot concerned an $18 annual surcharge on vehicles to support state parks. Prop 21 failed, implying 25% of these parks risk closure. Voting patterns at the Census tract level depend on gross price, incomes, age profiles, political ideology, environmental preferences, the availability of local substitutes, and park salience. We simulate counterfactual scenarios under which Prop 21 might have passed and use county-level hold-out samples to illustrate the predictive ability of our model. The California Air Resources Board is slowly phasing out perchloroethylene as the main input in dry cleaning operations in the state. Exploiting differential implementation of this regulation between SCAQMD (South Coast Air Quality Management District) and the rest of the state, we examine the effect of this regulation on the propensity for dry cleaning businesses to exit the industry. We find that regulation has encouraged early exit from the industry in some cases. We also find that regulation decreased ambient concentrations of perchloroethylene in the atmosphere. This dissertation contains both published and unpublished co-authored material. It also contains an appendix for chapter II as a supplemental file.
Open Access
Essays in Environmental Economics
(University of Oregon, 2018-09-06) Mueller, Rosie; Cameron, Trudy Ann
This research examines both health effects and market responses from local changes in environmental quality. Both can be of significant interest to policy makers. I examine the health effects of population exposure to pollution from a primary resource-extraction industry and the housing-market effects when an area is officially designated as being at risk from water pollution exposure. In Chapter II, I examine how adult mortality rates are affected by coal-mining activity in Appalachia. I find increased surface coal-mining activity leads to increased mortality attributable to internal causes, specifically among the population over age 65. Increased surface coal mining is most significantly associated with increases in mortality from cardiovascular disease, suggesting air pollution as a plausible mechanism. Chapter III documents the association between infant health and coal-mining activity in Appalachia. Descriptive evidence implies infant health outcomes are worse in certain Appalachian coal counties compared to other parts of the U.S., but after controlling for other sources of observed and unobserved heterogeneity, I find no evidence that changes in surface coal-mining activity directly affect birth outcomes in these counties. In Chapter IV, I evaluate the effect of a policy intervention in Oregon which provided information to residents regarding potential exposure to groundwater pollution from agricultural runoff. I find that this policy led to an increase in home prices for properties that were more likely to be reliant on public water supplies, suggesting that consumer demand shifted away from well-water-dependent properties that were at risk of contamination. The heterogeneity of the policy effect is consistent with a heightened awareness of groundwater quality among residents and housing market participants after the information was announced.
Open Access
Essays on Development and Health Economics
(University of Oregon, 2022-10-04) Mitchell-Nelson, Joseph; Cameron, Trudy Ann
This research examines the role of culture in two specific contexts--World Bank project management and preferences for pandemic mitigation strategies--and contributes a novel econometric method for sample selection correction for choice experiments. Chapter 2 explores how the cultural background of World Bank project leaders affects the success of foreign aid projects, using a constructed measure of cultural proximity between project leaders and the countries where their projects take place. A principal-agent model of project leaders' incentives predicts that cultural proximity and a recipient country's institutional quality will interact to affect project quality. This prediction is borne out in data on project evaluations of 1,946 World Bank projects. Chapter 3 examines individual preferences for local COVID-19 lockdown policies that force trade-offs between, on the one hand, deaths and illnesses averted, and, on the other hand, employment and income. We field a choice experiment to 993 respondents to determine individuals' willingness to make these trade-offs, and we specifically examine the effect of federal unemployment insurance on these decisions. We find that a stronger social safety net for the unemployed makes individuals, on average, \textit{more willing} to accept county-level income losses but \textit{less willing} to accept increases in county-level unemployment rates in exchange for reduced COVID-19 deaths and illnesses. Split sample regressions reveal that this puzzling change in preferences is driven almost entirely by politically moderate and conservative respondents. Finally, chapter 4 proposes a new method for sample selection correction for conditional logit models based on mixed logit estimation methods. Survey-based research methods can produce biased estimates if the responding sample is systematically different from the population of interest. A seminal paper by \cite{Heckman_Ecta79} demonstrates how an explicit response/non-response model can be combined with a least-squares-based outcome model to correct for selection bias, but this approach is inappropriate for the conditional logit choice models typically used to analyze the data from choice experiments. Our new method, however, is appropriate for addressing sample selection in choice experiments, which are often used to value goods, services, and social policies that are not traded in markets. This dissertation includes previously unpublished co-authored material.
Open Access
Essays on Economic Development and Climate Change
(University of Oregon, 2015-08-18) Fitch-Fleischmann, Benjamin; Cameron, Trudy Ann
The first essay considers the relative effectiveness of government and non-governmental organizations (NGOs) as channels to allocate resources. I use a catastrophic climate-related shock--Hurricane Mitch--to examine the political economy of these channels of aid distribution at the micro level. I combine extensive data on aid received by Nicaraguan households with data on municipal election outcomes and an exogenous, precipitation-based measure of hurricane impact. I find that the hurricane had long-lasting effects on the aid received by households from both NGOs and the government. In the short term, however, the government did not provide aid according to the objective measure of hurricane damage but instead provided aid along political lines. The second essay presents estimates of a relationship between extreme hot temperatures during gestation and a child's subsequent physical well-being in a sample of children in Peru, thus extending existing evidence constructed from U.S. data. Estimates are constructed using high-resolution gridded climate data and geo-coded household surveys. The results suggest that a period of extreme heat (a month whose average temperature is more than 2 standard deviations above the local average) in the period 1 to 3 months before birth is associated with lower weight at birth and a reduction in height (measured 1 to 59 months after birth) that cannot be fully explained by birth weight. There is no evidence of differential maternal investment, as measured by duration of breastfeeding, according to a child's exposure to extreme heat during gestation. The third essay asks whether improved treatment of HIV/AIDS in Africa can be achieved simply by paying health workers to do more. I present estimates of the impact of financial incentives paid to individual workers at public health facilities in Mozambique. The results suggest that piece-rate incentives increased the delivery of five out of fourteen health services for which treatment effects can be identified, with estimated increases ranging from 34 to 157 percent, depending on the particular service. I find no evidence of a corresponding decrease in the delivery of services that are not financially incentivized, suggesting that there is no "crowding out" of intrinsic motivation.
Open Access
Essays on Income Inequality and the Environment
(University of Oregon, 2016-10-27) Voorheis, John; Cameron, Trudy Ann
This dissertation considers two of the most pressing concerns of the current time, income inequality and exposure to pollution, and provides evidence that these two concerns may in fact be causally linked. In order to do this, I assemble novel datasets on income inequality and pollution exposure, and propose an strategy for causally identifying the effect of the former on the latter. In the first substantive chapter, I develop a new dataset on income inequality measured at the US state and metropolitan area level. I compare the trends in income inequality measured using different income definitions. In general, pre-tax, pre-transfer income inequality has increased in most states since 1980, but post-fiscal income inequality has seen slow or no growth since about 2000. I conduct inference on how income inequality has changed using a semi-parametric bootstrap method, and consider potential correlates with state-level income inequality. I find that de-unionization is perhaps the most important factor driving rising inequality. In the second substantive chapter, I leverage satellite-derived remote sensing data on ground-level concentrations for two important pollutants (NOx and PM2.5) to measure the distribution of pollution exposure. I propose a dashboard approach to measuring environmental inequality and environmental justice, proposing and applying several candidate measures to the satellite datasets. I find that environmental inequality has largely decreased since 1998, as has average exposure. I consider potential correlations between neighborhood demographics and the distribution of exposure, but find inconclusive results. In the third substantive chapter, I attempt to resolve this ambiguity by considering whether rising income inequality within metropolitan areas (the subject of the first chapter) might causally affect the distribution of exposure across people (the subject of the second). Using a simulated instrumental variables identification strategy designed to address potential endogeneity due to locational sorting, I find that income inequality decreases the average level of exposure, but increases environmental inequality. I argue this is consistent with the benefits of pollution reduction accruing to the most advantaged, and provide evidence that this may work through the political system: inequality increases the responsiveness of politicians to the environmental demands of the rich.
Embargo
Essays on the Recreational Value of Avian Biodiversity
(University of Oregon, 2016-10-27) Kolstoe, Sonja; Cameron, Trudy Ann
This dissertation uses a convenience sample of members of eBird, a large citizen science project maintained by the Cornell University's Laboratory of Ornithology, to explore the value of avian biodiversity to bird watchers. Panel data (i.e. longitudinal data) are highly desirable for preference estimation. Fortuitously, the diaries of birding excursions by eBird members provide a rich source of spatial data on trips taken, over time by the same individuals, to a variety of birding destinations. Origin and destination data can be combined with exogenous species prevalence information. These combined data sources permit estimation of utility-theoretic choice models that allow derivation of the marginal utilities of avian biodiversity measures as well as the marginal utility of net income (i.e. consumption of other goods and services). Ratios of these marginal utilities yield marginal willingness to pay (MWTP) estimates for numbers of bird species (or numbers of species of different types, in richer specifications). MWTP for levels of other attributes of birding destinations are also derived (e.g. ecosystem type, management regime, seasonal variations, a time trend).\\ The chapters are organized as follows: Chapter 2 is a stand-alone paper that demonstrates the feasibility of a travel-cost based random utility model with the eBird data. This chapter focuses on measuring the total number of bird species at each birding hotspot in Washington and Oregon states. This chapter does not differentiate among types of birders beyond using their recent birding activities in an analysis of habit formation or variety-seeking behavior. For this model, beyond past behavior, a representative consumer is postulated. Chapter 3 starts from the basic specifications identified in Chapter 2 and explores heterogeneous preferences among consumers as well as their preferences for species richness and for different categories of birds. This chapter explores whether different types of birds are relatively more attractive to different types of birders (for example, by gender or by age or by neighborhood characteristics and educational attainment). Chapter 4 is an extension of the work in Chapter 3 to explore how changing site attributes in the face of climate change effects birder welfare. This dissertation includes previously unpublished co-authored material.
Open Access
Evidence of Environmental Migration: Housing values alone may not capture the full effects of local environmental disamenities
(University of Oregon, Dept of Economics, 2005-01-01) Cameron, Trudy Ann; McConnaha, Ian
In hedonic property value models, economists typically assume that changing perceptions of environmental risk should be captured by changes in housing prices. However, for long-lived environmental problems, we find that many other features of neighborhoods seem to change as well, because households relocate in response to changes in perceived environmental quality. We consider spatial patterns in census variables over three decades in the vicinity of four Superfund sites. We find many examples of moving and staying behavior, inferred from changes in the relative concentrations of a wide range of socio-demographic groups in census tracts near the site versus farther away.
Open Access
Extreme Weather Events and Rural-Urban Migration
(University of Oregon, 2012) Saif, Raisa; Saif, Raisa; Cameron, Trudy Ann
In numerous regions around the globe, climate change can be expected to change the pattern of severe weather events. Migration flows have been systematically larger the higher the proportion of the population in urban areas in the destination county relative to the origin county. Richer models demonstrate that the effects of a number of different types of extreme weather events (i.e. flooding, heat waves, and wildfires) in the origin county on county-to-county migration flows are statistically significantly greater when the destination county is more urbanized. The effect of the number of fatalities from flooding and heat waves in the origin county on migration flows is also amplified when the destination county is more urbanized. Thus it appears that even in a developed country like the U.S. extreme weather events still exacerbate rural-to-urban migration flows.
Open Access
Individual Option Prices for Climate Change Mitigation
(University of Oregon, Dept. of Economics, 2002-07-20) Cameron, Trudy Ann
Willingness to pay for climate change mitigation depends on people's perceptions about just how bad things will get if nothing is done. Individual subjective distributions for future climate conditions are combined with stated preference discrete choice data over alternative climate policies to estimate individual option prices (the appropriate ex ante welfare measure in the face of uncertainty) for climate change mitigation. We find significant scope effects in the estimated option prices according to both expected conditions and degree of uncertainty.
Open Access
Risk Aversion and Information Acquisition Across Real and Hypothetical Settings
(University of Oregon, 2012) Taylor, Matthew; Taylor, Matthew; Cameron, Trudy Ann
I collect data on subjects' information acquisition during real and hypothetical risky choices using process-tracing software called Mouselab. I also measure subjects' cognitive ability using the cognitive reflective test (CRT). On average, measured risk preferences are not significantly different across real and hypothetical settings. However, cognitive ability is inversely related to risk aversion when choices are hypothetical, but it is unrelated when the choices are real. This interaction between cognitive ability and hypothetical setting is consistent with the notion that some individuals, specifically higher-ability individuals, treat hypothetical choices as "puzzles" and may help explain why some studies find that subjects indicate that they are more tolerant of risk when they make hypothetical choices than when they make real choices. On average, subjects demonstrate a similar degree of consistency across settings, and there are also no significant differences across settings in the amount of time subjects take to make a choice, the amount of information they acquire, or how they distribute their attention. I also find evidence to suggest that subjects acquire information in a manner consistent with the implicit calculation of expected utility. Specifically, individuals do not merely make choices "as if" they are integrating probabilities and outcomes, it appears that they actually are. Moreover, as they progress through a series of choices in a commonly used risk preference elicitation method, their information acquisition becomes progressively more consistent with integration models. Finally, on average, individuals appear to acquire information in real and hypothetical settings in similar ways.
Open Access
Scenario Adjustment in Stated Preference Research
(University of Oregon, Dept of Economics, 2009-11-22) Cameron, Trudy Ann; DeShazo, J. R.; Johnson, Erica H.
Stated preference (SP) survey methods have been used increasingly to assess willingness to pay for a wide variety of non-market goods and services, including reductions in risks to life and health. Poorly designed SP studies are subject to a number of well-known biases, but many of these biases can be minimized when they are anticipated ex ante and accommodated in the study’s design or during data analysis. We identify another source of potential bias, which we call “scenario adjustment,” where respondents assume that the substantive alternative(s) in an SP choice set, in their own particular case, will be different than the survey instrument describes. We use an existing survey, developed to ascertain willingness to pay for private health-risk reduction programs, to demonstrate a strategy to control and correct for scenario adjustment in the estimation of willingness to pay. This strategy involves data from carefully worded follow-up questions and ex post econometric controls for each respondent’s subjective departures from the intended choice scenario. Our research has important implications for the design of future SP surveys.
Open Access
Superfund Taint and Neighborhood Change: Ethnicity, Age Distributions, and Household Structure
(University of Oregon, Dept. of Economics, 2003-12) Cameron, Trudy Ann; Crawford, Graham D.
Certain sociodemographic groups often seem to be relatively more concentrated near environmental hazards than in the surrounding community. It is well-known that snapshot cross-sectional statistical analyses cannot reveal how residential mobility for these different groups reacts to changing public perceptions of environmental hazards. Decennial panel data over four census periods, for census tracts surrounding seven different urban Superfund localities, allow us to examine how ethnicities, the age distribution and family structure vary over time with distance from these major environmental disamenities. If the slope of the distance profile decreases over time, the group in question could be argued to be “coming to the nuisance.” We find a lot of statistically significant movement, including some evidence of minority move-in and increasing relative exposure of children, especially those in singleparent households. However, it appears to be hard to make generalizations, across localities, about the mobility patterns for different groups. This heterogeneity may account for the difficulty other researchers have experienced in identifying systematic effects in data that are pooled across different environmental hazards. Changes over time in the sociodemographic mix near Superfund sites may also help explain differences in the extent to which housing prices rebound after cleanup commences.
Open Access
Test of Choice Set Misspecification for Discrete Models of Consumer Choice
(University of Oregon, Dept. of Economics, 2001-11-05) DeShazo, J. R.; Cameron, Trudy Ann; Saenz, Manrique, 1971-
We develop and evaluate a test of choice set misspecification for a multinomial logit choice model. This test determines whether the choice set designated by the researcher mistakenly assigns relevant substitutes to the numeraire good. We develop this test by generalizing the traditional McFadden-type conditional logit model to evaluate whether the traditional model is conditioned on an overly restrictive set of substitution possibilities. The test has a convenient feature: while it requires information on potentially relevant, but omitted, substitute goods, it does not require the researcher to observe consumers? choices among these omitted potential substitutes if they select the numeraire good (which contains these omitted substitutes). A comparison of the traditional multinomial logit choice model and our more general model suggests that choice set misspecification may produce biased parameters that distort welfare estimates to a consequential extent.