about
> education
- Ph.D., University of Maryland, 2015
- M.S., University of Maryland, 2014
- M.S., North Carolina State University, 2011
- B.A., Ithaca College, 2009
> appointments
- [2023–present] — Associate Professor, School of Economics, Georgia Institute of Technology
- [2019–present] — University Fellow, Resources for the Future
- [2020–2023] — Assistant Professor, School of Economics, Georgia Institute of Technology
- [2019–2020] — Research Director, Energy & Environment Lab, University of Chicago
- [2015–2019] — Fellow, Resources for the Future
research
> publications
[abstract] In this review, I explore the economic dimensions of equity and affordability in urban residential water pricing. I summarize the growing literature on water affordability and discuss its relationship to more common studies of distributional issues in water demand. I also explore how utilities use various rate structures, such as increasing block rates, to address affordability concerns, emphasizing empirical evidence on the ineffectiveness of these rate structures in achieving equity goals. Moreover, I discuss the design of customer assistance programs in alleviating burdens on low-income households and summarize the scant evidence of the effectiveness of these programs. Ultimately, I highlight the need for more empirical evaluations of equity-focused programs and a greater focus on the distributional consequences of water management strategies to ensure equitable access to this essential resource.
[abstract] Public good provision is often determined through referendums by voters, who weigh benefits against costs. However, perceptions of benefits and costs may be incorrect, which could in turn lead to voter error and misallocation of public goods. Using real-world referendums, we evaluate voter perceptions of the private costs of providing public goods by conducting three exit polls of New England voters and an online survey of California voters. By comparing cost perceptions to actual tax incidence, we find pervasive evidence that voters misperceive costs. Fewer than 20% of voters in our samples reported perceived costs within 25% of estimated actual costs. These findings are unsurprising given the ubiquity of opaque language explaining the financial consequences of public good referendums. In addition, our analysis suggests that actual costs have no statistical bearing on voter choice, but at least in the New England sample, voter approval is affected by perceived costs. Thus, a substantial proportion of voters are making decisions based in part on inaccurate costs, which in some cases lead to people voting against their preferences and potential misallocation of public funds. Further, researchers who match voter approval with estimated actual cost are unlikely to obtain accurate cost responsiveness or valuation estimates.
[abstract] Can automation complement economic incentives? We explore this question by randomly encouraging households to activate a feature on their existing smart thermostat that automates responsiveness to time-of-use electricity pricing. The feature reduces air conditioning use during the highest-priced afternoon period, raising indoor temperatures above a household's preferred temperature, primarily for customers who are typically home during the day. Customers infrequently override the feature when they experience discomfort, suggesting that they are willing to trade off monetary savings for small increases in discomfort. Automation thus enables low-cost changes in household energy use, with potentially large electricity supply-cost reductions at scale.
[abstract] Visitation to National Parks in the United States increased by more than 25% since 2010, rising from roughly 70 to 90 million annual visitors. Anecdotes suggest that this increase was driven by the advent of social media in the early-to-mid 2010s, generating a new form of exposure for parks, and has led to concerns about overcrowding and degradation of environmental quality. However, there is little empirical evidence on the role of social media in influencing recreation decisions. Here, I construct a dataset on social media exposure (SME) for each National Park and relate that exposure to changes in visitation over the last two decades. High SME parks see visitation increase by 16 to 22% relative to parks with less exposure, which comes with a concomitant increase in revenue. Low SME parks have no, or negative, changes in visitation. These estimates account for unobserved park heterogeneity and are based on an instrumental variables strategy that predicts exposure with a park's online popularity prior to the social media era. Additional analysis suggests that recent social media posts that include media attachments increase visitation, while posts with negative sentiment reduce visitation. These results provide insight for the National Park Service--which faces more than $22 billion in deferred maintenance costs and is considering policy options to manage demand--as well as for management of recreation on other public lands.
[abstract] We provide new evidence on motivations for voluntary contributions to public goods in a natural setting. Using natural language processing on users' Twitter posts, we measure revealed sentiment changes before and after making a donation to Wikipedia. We find strong evidence that sentiment improves in the hour and minutes directly before contributing, which we call 'preheating'. Results are robust to alternative fixed effects and approaches to inference and supported by a complementary online experiment with randomised mood inducement among Twitter users. Preheating suggests that affective states influence giving in addition to reward-seeking, utility-maximising behaviour that has been documented in other contexts.
[abstract] We investigate how successfully machine-learning (ML) prediction algorithms can be used to estimate causal treatment effects in electricity demand applications with nonexperimental data. We use three prediction algorithms--XGBoost, random forests, and LASSO--to generate counterfactuals using observational data. Using those counterfactuals, we estimate nonexperimental treatment effects and compare them to experimental treatment effects from a randomized experiment for electricity customers who faced critical-peak pricing and information treatments. Our results show that nonexperimental treatment effects based on each algorithm replicate the true treatment effects, even when only using data from treated households. Additionally, when using both treatment households and nonexperimental comparison households, standard two-way fixed effects regressions replicate the experimental benchmark, suggesting little benefit from ML approaches over standard program evaluation methods in that setting.
[abstract] We estimate time-for-money tradeoffs for cyclists by exploiting revealed behavior in response to a bikesharing program's discontinuous, "notched" pricing structure. The cost of a bicycle trip increases from $0 to $1 after 30 min. We observe cyclists adding time to their trip by checking-in at an intermediate station along their route to avoid the price, thus revealing their value of saving time (VST) cycling. Estimates of the VST for cycling are close to the minimum wage or roughly 20% of hourly wages implied by median incomes. These estimates are smaller than comparable estimates for automobiles, likely driven by leisure benefits of cycling. Although bicycle commuters exhibit somewhat larger VSTs, our results across user type, time, and route-specific characteristics are relatively homogeneous, suggesting a more fundamental time–-money tradeoff. Additionally, we estimate small changes along extensive margins in response to a large price increase, but changes along intensive margins are virtually nonexistent.
[abstract] In the US, the cost of water and wastewater services is rising three-times faster than inflation. Over the next 20–-25 years, required investments in water infrastructure are estimated to exceed $1 trillion, further increasing service costs. Combined with stagnating income levels, especially for poor households, increased costs will likely aggravate water affordability issues. Here, we document the extent of water affordability concerns in the US across income, geography, and race. We find that 10% of households face water affordability concerns, defined as expenditures on essential water and sewer services greater than 4.5% of annual household income. Households in the lowest income decile pay on average 6.8% of their annual income on water and sewer service. Our estimates are based on a large-scale data set on water and sewer rates matched with Census block-group-level socioeconomic characteristics and covering approximately 45% of the US population. We demonstrate that using median household income at the county level drastically understates the extent of the water affordability problem. Additionally, we find that the number of households facing affordability concerns is positively associated with the proportion of black residents and negatively associated with Hispanic residents even after conditioning on prices and poverty levels. Lastly, we show that self-sufficient water affordability policies that provide a lump-sum rebate to low-income households and are paid for by income taxes redistribute the burden borne by low-income customers with fewer unintended consequences for non-essential consumption than policies that change marginal incentives for water and sewer consumption.
[abstract] Nonmarket damages are largely missing from aggregate climate impact estimates, especially those related to outdoor recreation. One simple approach to measuring these missing impacts is to estimate dose-response functions to weather, and then to combine these functions with benefits transfer approaches to value the gained or lost recreational opportunities. In this paper, we analyze the potential and shortcomings of such an approach. Although seemingly simplistic, we show that this approach has attractive theoretical properties and can provide exact or conservative estimates of surplus changes under standard assumptions that are commonly used in the valuation literature. We assess the accuracy of this approximation in the context of several prior studies of environmental quality changes, and we also use this framework to generate illustrative climate impacts for outdoor recreation using nationally representative time-use data.
[abstract] Research on the economics of climate change has advanced drastically in the last 20 years, but how has treatment of climate change evolved in the classroom? Many economics, environmental studies, and public policy departments now offer climate economics and climate policy courses, but it is unclear what topics are covered, what resources are used, and with what knowledge students are expected to walk away. In this paper, we assess what topics are (or should be) taught in climate economics courses, how those topics have shifted over time, and what learning goals are articulated for students. Our assessment is based on a review of common teaching materials, an informal collection of syllabi, and the results from a survey of environmental and resource economists. Overall, there is a reasonable degree of consensus on the key topics for inclusion across survey respondents, although some topics may complement or crowd out those in standard courses in environmental and resource economics. Despite relatively broad consensus on topics, we find that climate economics courses can diverge greatly in practice, perhaps because there is no central teaching resource used across courses. We conclude constructively by proposing a set of learning goals that instructors can draw from and build upon, which we hope will aid in developing shared expectations for what students will learn in a climate economics course.
[abstract] We estimate economic impacts from decaying water infrastructure in the United States. Using water main breaks in Washington, DC, and a yearlong panel of hourly traffic speeds, we estimate causal effects of water main failures on traffic congestion. We use k-means clustering to create clusters of streets that are similar to each other: treated observations are compared to other units in the cluster. We identify heterogeneous treatment effects algorithmically while retaining straightforward standard error calculations. We find strong evidence of heterogeneous treatment effects across clusters but small welfare impacts of water main breaks on traffic patterns overall.
[abstract] There is extensive research documenting the economic consequences of climate change, yet our understanding of climate impacts on nonmarket activities remains incomplete. Here, we investigate the effect of weather on recreation demand. Using data from 27 million bicycle trips in 16 North American cities, we estimate how outdoor recreation responds to daily weather fluctuations. We find empirically that cyclists dislike cold temperatures much more than hot temperatures, suggesting potential gains from warming. However, the overall response to extreme heat is mitigated, in part, by intraday adaptation towards recreating during cooler times of day. Combining these estimates with time-use survey data and climate projections, our models suggest annual surplus gains of $894 million from climate-induced cycling by mid-century.
[journal link] [blog]
[abstract] Applied econometricians frequently apply the inverse hyperbolic sine (or arcsinh) transformation to a variable because it approximates the natural logarithm of that variable and allows retaining zero-valued observations. We provide derivations of elasticities in common applications of the inverse hyperbolic sine transformation and show empirically that the difference in elasticities driven by ad hoc transformations can be substantial. We conclude by offering practical guidance for applied researchers.
[abstract] Observed changes in weather can reveal marginal impacts of climate change on economic outcomes and the potential for adaptation. When modeling the nonlinear relationship between weather and changes in economic outcomes empirically, model choice can confound the interpretation of marginal and percentage effects and their respective confidence intervals. I present a simple solution for better characterizing semi-elasticities of nonlinear climate damages, and evaluate its relevance in interpreting empirical climate damages. For small marginal effects, the implications of this interpretation error is small; for larger effects, however, the misinterpretation error can be substantial.
[abstract] Water withdrawals for the energy sector are the largest use of fresh water in the United States. Using an econometric model of monthly plant-level electricity generation levels between 2001 and 2012, we estimate the effect of water scarcity on the US electricity fuel mix. We find that hydroelectric generation decreases substantially in response to drought, although this baseline generation is offset primarily by natural gas, depending on the geographic region. We provide empirical evidence that drought can increase emissions of CO2 and local pollutants. We quantify the social costs of water scarcity to be $330,000 per month for each plant that experiences a one-standard deviation increase in water scarcity (2015 dollars), a relationship that persists under future projections of water scarcity.
[abstract] This study explores the impact of bicycle-sharing infrastructure on urban transportation. We estimate a causal effect of the Capital Bikeshare on traffic congestion in the metropolitan Washington, D.C., area. We exploit a unique traffic dataset that is finely defined on a spatial and temporal scale. Our approach examines within-city commuting decisions as opposed to traffic patterns on major thruways. Empirical results suggest that the availability of a bikeshare reduces traffic congestion upwards of 4% within a neighborhood. In addition, we estimate heterogeneous treatment effects using panel quantile regression. Results indicate that the congestion-reducing impact of bikeshares is concentrated in highly congested areas.
[abstract] In this study, I estimate a causal effect of increased billing frequency on consumer behavior. I exploit a natural experiment in which residential water customers switched exogenously from bimonthly to monthly billing. Customers increase consumption by 3.5–5% in response to more frequent information. This result is reconciled in models of price and quantity uncertainty, where increases in billing frequency reduce the distortion in consumer perceptions. Using treatment effects as sufficient statistics, I calculate consumer welfare gains equivalent to 0.5–1% of annual water expenditures. Heterogeneous treatment effects suggest increases in outdoor water use.
[abstract] TWe compare experimental and nonexperimental estimates from a social and informational messaging experiment. Our results show that applying a fixed effects estimator in conjunction with matching to pre-process nonexperimental comparison groups cannot replicate an experimental benchmark, despite parallel pre-intervention trends and good covariate balance. The results are a stark reminder about the role of untestable assumptions–-in our case, conditional bias stability-–in drawing causal inferences from observational data, and the dangers of relying on single studies to justify program scaling-up or canceling.
[abstract] Pro-environmental preferences are being used increasingly in environmental policy. In this paper, I consider the role of heterogeneous green preferences for private provision of environmental goods that have both private and public characteristics. Under different assumptions of information available to a regulator, I characterize equilibrium properties of several mechanisms. I find incentive-compatible Nash equilibria that provide socially optimal public goods provision when the regulator can enforce individual consumption contracts, as well as when reported consumption contracts are supplemented with group penalties. Throughout the paper, I ground the exposition with examples of consumer behavior in the context of green electricity programs and goal setting for energy conservation.
[abstract] The efficiency properties of price and nonprice instruments for conservation in environmental policy are well understood. However, there is little evidence comparing the effectiveness of these instruments, especially when considering water resource management. We exploit a rich panel of residential water consumption data to examine heterogeneous responses to both price and nonprice conservation policies during times of drought while controlling for unobservable household characteristics. Our empirical models suggest that among owners of detached, single-family homes in six North Carolina municipalities, relatively low-income households are more sensitive to price and relatively high-consumption households are less sensitive to price. However, prescriptive policies such as restrictions on outdoor water use result in uniform responses across income levels, while simultaneously targeting reductions from households with irrigation systems and historically high consumption.
[abstract] Under complicated billing structures, the price to which consumers respond remains inconclusive. In this paper, I exploit a quasi-experiment to estimate a causal effect of price for residential water customers during the introduction of increasing block rates for a North Carolina utility. Perceived price is identified through a billing anomaly in which changes in marginal and average prices move in opposite directions. Empirical results contribute evidence that residential water customers respond to average price. Average price elasticity estimates vary from −0.43 to −1.14 across the distribution of consumption in triple-difference models, with an estimate of −0.31 in the tightest bandwidth of regression discontinuity specifications.
> working papers
[abstract] Behavioral nudges are popular instruments to promote prosocial behavior, particularly in settings with unpriced externalities. Nudges may interact with existing incentives, however, by crowding out intrinsic motivation or increasing price salience. We investigate the interaction of prices and nudges for water conservation by evaluating a randomized behavioral treatment on top of exogenous variation in marginal prices introduced by lot-size thresholds in nonlinear water rate structures. We find no consistent evidence that social comparisons generate more conservation among households that face larger monetary cost savings. Higher prices cause small and insignificant decreases in the magnitude of the behavioral treatment effect. Our results suggest that behavioral nudges can work when monetary incentives are small or lack salience.
[abstract] Using price incentives to allocate scarce resources is a core tenet of economics but may result in unpalatable distributional outcomes. We analyze the efficacy of prices as a means of inducing water conservation during severe drought by studying the introduction of surcharges enacted within existing nonlinear rate structures. Embedding machine learning counterfactual prediction methods within a demand framework to isolate exogenous price variation, we find evidence that households exhibit a significant demand response despite the temporary nature of surcharges. However, further investigation reveals that surcharges alone cannot explain a majority of the conservation observed despite steep price increases. "Budget-based" rates undercut scarcity signals by shielding large users from binding price increases, and surcharges themselves do little to reduce the regressivity of water expenditures. Simpler rate structures can dominate along equity dimensions, and their progressivity can be enhanced via lump-sum transfers within the rate structure.
[abstract] Municipal water utilities choose rates to recover costs, encourage conservation, and reduce burdens on low-income customers, which may deviate from optimal two-part tariffs. Theory suggests that prices should equal marginal cost with fixed costs recovered via fixed fees or alternative tax revenues. Using rate structure and municipal finance data for more than 700 utilities, I show that prices are discounted severely for low levels of consumption within nonlinear rate structures, leading to suboptimal usage and budget deficits, particularly in poorer and smaller communities. Marginal-cost pricing corrects allocative inefficiencies, and equity and cost-recovery goals can be achieved through more progressive approaches to fixed costs, which are both highly regressive and a large share of total costs.
[abstract] Do short-run weather shocks affect migration? I estimate how snow influences county-level migration in the Great Lakes region since 1970. I isolate responses to snow by comparing its effect on net migration across regions exposed to lake-effect snow (LES)--where cold air moving over a Great Lake leads to heavy snow downwind. Higher-than-average snowfall in LES regions leads to net population loss the following year. This response is strongest for young adults and for late-season snow. Snow has virtually no effect on migration in non-LES regions, suggesting that repeated exposure matters more than anomalous weather events.
[abstract]
> research in progress
> other writing & publications
teaching
> georgia institute of technology
- Fall 2022 CIOS Honor Roll
- 2023 Annual CIOS Award (one of 40 faculty across Georgia Tech)
- If you're interested in teaching materials for this course, please email me.
> previous
news & press
[social media and national parks]
- The Nevada Independent [09.12.2024] "Indy Environment: Tahoe's greatest challenges? Managing transportation and tourism"
- KDNK [09.11.2024] "Social media stampede for beautiful views"
- Los Angeles Times [09.01.2024] "This Joshua Tree search and rescue team tries to head off calamity before it strikes"
- The Guardian [08.18.2024] "The number of hikers visiting US national parks is increasing. So is the challenge of keeping them safe"
- Resources Radio [07.09.2024] "Loved to Death? Social Media and Rising Visitation to National Parks, with Casey Wichman"
- Outside Magazine [06.04.2024] "A New Study Finds Crowds at National Parks May Be Due to Social Media"
- Men's Journal [05.18.2024] "Study Finds the Impact Social Media Is Having on U.S. National Parks"
- CBS News (Minneapolis) [05.17.2024] "Social media is boosting national park visits, study finds"
- Alaska Public Media [05.16.2024] "New study says social media drives visitation in national parks, especially in Alaska"
- Sierra (The Magazine of the Sierra Club) [05.10.2024] "Are Social Media Videos Ruining the National Park Experience?"
- Mountain West News Bureau [04.15.2024] "Social media steers more visitors to national parks in Mountain West and beyond, study finds"
- Outdoors.com [04.03.2024] "Influencers Are Driving National Park Visitation—How Do We Feel About This?"
[charitable giving]
- Associated Press [08.03.2023] "Does being in a good mood make you more generous? Researchers say yes and charities should take note."
- Fortune [08.03.2023] "Beyond 'sadvertising': Charitable giving is more likely if potential donors are in a good mood, research suggests."
- Quartz [08.04.2023] "People who donate to charity seem to have one thing in common."
[water]
- Boston Globe [03.03.2025] "Rising water bills could swamp household budgets."
- Inside Climate News [06.17.2023] "As the Colorado River Declines, Water Scarcity and the Hunt for New Sources Drive up Rates"
- China Daily [07.19.2022] "Water affordability affects low-income US communities."
- New Scientist [11.10.2020] "When water runs short, how do you get people to use their fair share?"
- Politico [03.17.2016] "Allow only a glass half full, or charge more to fill it up?"
- The Washington Post [09.24.2014] "Why inequality makes it harder to stop climate change"
- Vox [12.20.2014] "One small study that explodes the myth that inequality is efficient"
[energy & climate policy]
- Atlanta Journal Constitution [06.12.2025] "This tiny Georgia town worries cut in federal incentives will burst its bubble"
- New York Times [01.13.2025] "Are Smart Thermostats Worth the Money?"
- The Conversation [07.26.2023] "Persuading businesses and people to reduce climate emissions is key to slowing climate change"
- AARP [06.01.2021] "What You Need to Know About Climate Change"
- Bloomberg [07.26.2019] "Navigator: Baby It's Hot Outside."
- CityLab [07.26.2019] "It's getting too damn hot to have fun in the summer"
- National Academies of Sciences' Report, "Valuing Climate Damages," cited in President Biden's Executive Order on Protecting Public Health and the Environment [01.20.2021]
- The Washington Post [12.12.2017] "The Energy 202"
- Axios [12.11.2017] "One interesting thing: bike-sharing and global warming"
- Vox [10.17.2017] "Scott Pruitt's quest to kill Obama's climate regulations is deeply shady"
- Utility Dive [08.31.2017] "Carbon Calculus: More States Are Adding Carbon Costs to Utility Planning Guidelines"
[urban transportation]
- Interview on KJZZ (Phoenix Public Radio) [01.17.2018] "Bike Share Industry Evolution Playing Out In Phoenix Metro Area"
- The Economist [12.21.2017] "How bike-sharing conquered the world"
- Gas2.org [09.18.2015] "Bikesharing Programs Shown To Cut Traffic Congestion"
- Curbed DC [09.14.2015] "Capital Bikeshare is Booming—and Helping Traffic Too"
- Vox [09.06.2015] "Study: Bike Share Has (Slightly) Reduced Congestion in Washington, DC"
- WTOP [08.27.2015] "Study: Capital Bikeshare Easing Local Traffic Woes"