Showing 51 - 60 of 84 Items
Projected land-use change impacts on ecosystem services in the United States
Date: 2014-05-20
Creator: Joshua J. Lawler, David J. Lewis, Erik Nelson, Andrew J. Plantinga, Stephen, Polasky, John C. Withey, David P. Helmers, Sebastián Martinuzzi, Derric Penningtonh
Access: Open access
- Providing food, timber, energy, housing, and other goods and services, while maintaining ecosystem functions and biodiversity that underpin their sustainable supply, is one of the great challenges of our time. Understanding the drivers of land-use change and how policies can alter land-use change will be critical to meeting this challenge. Here we project land-use change in the contiguous United States to 2051 under two plausible baseline trajectories of economic conditions to illustrate how differences in underlying market forces can have large impacts on land-use with cascading effects on ecosystem services and wildlife habitat. We project a large increase in croplands (28.2 million ha) under a scenario with high crop demand mirroring conditions starting in 2007, compared with a loss of cropland (11.2 million ha) mirroring conditions in the 1990s. Projected land-use changes result in increases in carbon storage, timber production, food production from increased yields, and >10% decreases in habitat for 25% of modeled species. We also analyze policy alternatives designed to encourage forest cover and natural landscapes and reduce urban expansion. Although these policy scenarios modify baseline land-use patterns, they do not reverse powerful underlying trends. Policy interventions need to be aggressive to significantly alter underlying land-use change trends and shift the trajectory of ecosystem service provision.
Using 'big data' to explain visits to lakes in 17 US states
Date: 2020-07-01
Creator: Erik Nelson, Maggie Rogers, Spencer Wood, Jesse Chung, Bonnie, Keeler
Access: Open access
- We use large dataset on US lakes from 17 states to estimate the relationship between summertime visits to lakes as proxied by social media use and the lakes' water quality, amenities, and surrounding landscape features and socioeconomic conditions. Prior to estimating these relationships we worked on 1) selecting a parsimonious set of explanatory variables from a roster of more than 100 lake attributes and 2) accounting for the non-random pattern of missing water quality data. These steps 1) improved the interpretability of the estimated visit models and 2) widened our estimated models' scope of statistical inference. We used Machine Learning techniques to select parsimonious sets of explanatory variables and multiple imputation to estimate water quality at lakes missing this data. We found the following relationships between summertime visits to lake and their attributes across the 17-state region. First, we estimated that every additional meter of average summer-time Secchi depth between 1995 and 2014 was associated with at least 7.0% more summer-time visits to a lake between 2005 to 2014, all else equal. Second, we consistently found that lake amenities, such as beaches, boat launches, and public toilets, were more powerful predictors of visits than water quality. Third, we also found that visits to a lake were strongly influenced by the lake's accessibility and its distance to nearby lakes and the amenities the nearby lakes offered. Finally, our results highlight the biased results that "big data"-based research on recreation can generate if non-random missing observation patterns in the data are not corrected.
Invisible Women: Entrepreneurship, Innovation, and Family Firms in Nineteenth-Century France
Date: 2016-02-25
Creator: B. Zorina Khan
Access: Open access
- The French economy has been criticized for a lack of integration of women in business and for the prevalence of inefficient family firms. A sample drawn from patent and exhibition records is used to examine the role of women in enterprise and invention in France. Middle-class women were extensively engaged in entrepreneurship and innovation, and the empirical analysis indicates that their commercial efforts were significantly enhanced by association with family firms. Such formerly invisible achievements suggest a more productive role for family-based enterprises, as a means of incorporating relatively disadvantaged groups into the market economy as managers and entrepreneurs. This business model .... melds entrepreneurial passion with a long family tradition. - Wendel Company (1704-2014) 1
Exchange Rate Regimes and Nominal Wage Comovements in a Dynamic Ricardian Model
Date: 2013-10-28
Creator: Yao Tang, Yoshinori Kurokawa, Jiaren Pang
Access: Open access
- We construct a dynamic Ricardian model of trade with money and nominal exchange rate. The model implies that the nominal wages of the trading countries are more likely to exhibit stronger positive comovements when the countries fix their bilateral exchange rates. Panel regression results based on data from OECD countries from 1973 to 2012 suggest that countries in the European Monetary Union (EMU) experienced stronger positive wage comovements with their main trade partners. When we restrict the regression to the subsample of the EMU countries, we find a significant increase in wage comovements after these countries joined the EMU in 1999 compared to the pre-euro era. In comparison, when the sample is restricted to the non-EMU countries, we find no evidence that non-currency union pegs affected the wage comovements.
Observations beyond the 2-year impact window
Date: 2021-01-01
Creator: José Edwards, Stephen Meardon
Access: Open access
- In 2018, Clarivate Analytics, publisher of the Web of Science Journal Citation Reports (JCR), suppressed publication of the 2017 Journal Impact Factor (JIF) for three of the four journals that it then indexed in the academic field of history of economics. Clarivate judged one of the journals, History of Economic Ideas (HEI), to be the “donor” of citations that distorted the impact factors of the European Journal of the History of Economic Thought (EJHET) and the Journal of the History of Economic Thought (JHET). The other journal, History of Political Economy (HOPE), was not included in that judgment. Our purpose is to define the JIF, summarize the controversy that gave rise to this symposium, and discuss methodologically and historically some of the problems with the use of citation indexes in general and the JIF in particular. We show how these problems pertain differently to the scholarly field of the history of economics than to economics in general. In so doing we also introduce the following five articles of this symposium.
Environmental, economic, and energetic costs and benefits of biodiesel and ethanol biofuels
Date: 2006-07-25
Creator: Jason Hill, Erik Nelson, David Tilman, Stephen Polasky, Douglas, Tiffany
Access: Open access
- Negative environmental consequences of fossil fuels and concerns about petroleum supplies have spurred the search for renewable transportation biofuels. To be a viable alternative, a biofuel should provide a net energy gain, have environmental benefits, be economically competitive, and be producible in large quantities without reducing food supplies. We use these criteria to evaluate, through life-cycle accounting, ethanol from corn grain and biodiesel from soybeans. Ethanol yields 25% more energy than the energy invested in its production, whereas biodiesel yields 93% more. Compared with ethanol, biodiesel releases just 1.0%, 8.3%, and 13% of the agricultural nitrogen, phosphorus, and pesticide pollutants, respectively, per net energy gain. Relative to the fossil fuels they displace, greenhouse gas emissions are reduced 12% by the production and combustion of ethanol and 41% by biodiesel. Biodiesel also releases less air pollutants per net energy gain than ethanol. These advantages of biodiesel over ethanol come from lower agricultural inputs and more efficient conversion of feedstocks to fuel. Neither biofuel can replace much petroleum without impacting food supplies. Even dedicating all U.S. corn and soybean production to biofuels would meet only 12% of gasoline demand and 6% of diesel demand. Until recent increases in petroleum prices, high production costs made biofuels unprofitable without subsidies. Biodiesel provides sufficient environmental advantages to merit subsidy. Transportation biofuels such as synfuel hydrocarbons or cellulosic ethanol, if produced from low-input biomass grown on agriculturally marginal land or from waste biomass, could provide much greater supplies and environmental benefits than food-based biofuels. © 2006 by The National Academy of Sciences of the USA.
Projecting global land-use change and its effect on ecosystem service provision and biodiversity with simple models
Date: 2010-12-01
Creator: Erik Nelson, Heather Sander, Peter Hawthorne, Marc Conte, Driss, Ennaanay, Stacie Wolny, Steven Manson, Stephen Polasky
Access: Open access
- Background: As the global human population grows and its consumption patterns change, additional land will be needed for living space and agricultural production. A critical question facing global society is how to meet growing human demands for living space, food, fuel, and other materials while sustaining ecosystem services and biodiversity [1]. Methodology/Principal Findings: We spatially allocate two scenarios of 2000 to 2015 global areal change in urban land and cropland at the grid cell-level and measure the impact of this change on the provision of ecosystem services and biodiversity. The models and techniques used to spatially allocate land-use/land-cover (LULC) change and evaluate its impact on ecosystems are relatively simple and transparent [2]. The difference in the magnitude and pattern of cropland expansion across the two scenarios engenders different tradeoffs among crop production, provision of species habitat, and other important ecosystem services such as biomass carbon storage. For example, in one scenario, 5.2 grams of carbon stored in biomass is released for every additional calorie of crop produced across the globe; under the other scenario this tradeoff rate is 13.7. By comparing scenarios and their impacts we can begin to identify the global pattern of cropland and irrigation development that is significant enough to meet future food needs but has less of an impact on ecosystem service and habitat provision. Conclusions/Significance: Urban area and croplands will expand in the future to meet human needs for living space, livelihoods, and food. In order to jointly provide desired levels of urban land, food production, and ecosystem service and species habitat provision the global society will have to become much more strategic in its allocation of intensively managed land uses. Here we illustrate a method for quickly and transparently evaluating the performance of potential global futures.
Suspense-optimal college football play-offs
Date: 2014-01-01
Creator: Jarrod Olson, Daniel F. Stone
Access: Open access
- U.S. college football’s traditional bowl system, and lack of a postseason play-off tournament, has been controversial for years. The conventional wisdom is that a play-off would be a more fair way to determine the national champion, and more fun for fans to watch. The colleges finally agreed to begin a play-off in the 2014-2015 season, but with just four teams, and speculation continues that more teams will be added soon. A subtle downside to adding play-off teams is that it reduces the significance of regular season games.We use the framework of Ely, Frankel, and Kamenica (in press) to directly estimate the utility fans would get from this significance, that is, utility from suspense, under a range of play-off scenarios. Our results consistently indicate that play-off expansion causes a loss in regular season suspense utility greater than the gain in the postseason, implying the traditional bowl system (two team play-off) is suspense-optimal. We analyze and discuss implications for TV viewership and other contexts.
Accounting for Gender Differences in Cultural Industries: Evidence from Film and the Fine Arts Access to this record is restricted to members of the Bowdoin community. Log in here to view.
Date: 2020-01-01
Creator: Madeleine Rose Dupré
Access: Access restricted to the Bowdoin Community
Economic Costs of Elevated Public Debt Levels During Banking-Crisis Recessions
Date: 2021-01-01
Creator: Gavin T Shilling
Access: Open access
- The Great Recession of 2007 and 2008 exposed the risks of excessive borrowing. We learned the essential economic principle that greater leverage harbors greater risk. Although this global economic contraction was driven primarily by booming private credit expansion, economically inefficient incentives in the public sector, such as short-term reelection concerns, may lead politicians to engage in rash deficit- financed, fiscal spending. The primary purpose of this research is to assess the economic costs of heightened, preexisting government leverage on real economic outcomes during recessionary periods, focusing on both banking and non-banking crisis recessions. In both advanced economies and emerging economies, this study confirms that banking recessions are associated with more severe economic contractions and more persistent output declines than normal recessions. In advanced economies, GDP recovers quickly and strongly with expansionary and supportive fiscal policy during low debt recessions, even with depressed private investment. While GDP recovers slowly and weakly with less expansionary fiscal policy during high debt recessions, even with strong private investment. Thus, the social marginal benefit of public sector investment exceeds the social marginal benefit of private sector investment in advanced economies. In emerging economies, GDP recovers quickly and strongly with strong private investment during high debt recessions, even with weak fiscal spending. While GDP recovers slowly and weakly with depressed private investment during low debt recessions, even with expansionary and supportive fiscal policy. Thus, the social marginal benefit of private sector investment exceeds the social marginal benefit of public sector investment in emerging economies.