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Full-Text Articles in Life Sciences

The Economic And Social Values Associated With Small South Dakota Lakes, Aaron Patrick Sundmark Jan 2019

The Economic And Social Values Associated With Small South Dakota Lakes, Aaron Patrick Sundmark

Electronic Theses and Dissertations

The valuation of small fishing lakes is a vital component in understanding the importance of fishing and of recreational resources, in general. Knowing the values associated with such lakes is essential when prioritizing management activities. The overall value of a lake as a resource for human benefit is estimated as the summation of both instrumental and non-instrumental values. Instrumental values consist of economic and utilitarian values, as well as the values that a lake provides from ecosystem services. Non-instrumental values consider what the lake is worth as a good of its own, such as aesthetic, moral, and spiritual values gained ...


An Empirical Analysis Of Climatic, Geographic, And Cultural Determinants Of International Tourism, Ethan Straus Jun 2018

An Empirical Analysis Of Climatic, Geographic, And Cultural Determinants Of International Tourism, Ethan Straus

Honors Theses

Each year, billions of people visit different countries all around the world. For many of those countries, tourism is their primary industry, leading to millions of jobs and dollars in revenue. It is expected that by 2020 total International Tourism Receipts will reach 2 trillion US dollars annually. Currently, tourism employs an estimated 200 million people around the world. With the continued progression of climate change, the tourism industry is facing a newfound threat. Global temperatures and the seal level are both expected to rise significantly by the end of the century. Additionally, the Intergovernmental Panel on Climate Change has ...


New Models To Estimate Costs Of Us Farm Programs, Xiaohong Zhu Jan 2016

New Models To Estimate Costs Of Us Farm Programs, Xiaohong Zhu

Graduate Theses and Dissertations

In this study, I extended the stochastic model built by Babcock and Paulson (2012) to conduct a one-year cost projection for crop insurance in order to investigate its feasibility of being solely provided by private firms. Based on the 52 years’ yield data from 1961 to 2012, the risk consequences from insuring crop yield and revenue against losses are estimated to be far beyond what private insurers could bear on their own. However, reinsurance from the government provides an attractive incentive to insurance firms. Among the six insurance policies researched in this study, the minimum expected net underwriting gains to ...


Honey Bees’ Impact On The U.S. Economy, James T. Chisel Jul 2015

Honey Bees’ Impact On The U.S. Economy, James T. Chisel

Economics Theses

Since Colony Collapse Disorder became front-page news in 2006, popular literature ranging from news articles to White House documents has cited the value that honey bees provide. These numbers in articles often are inconsistent and rarely cite the origin of the stated value. This paper examines the major studies on the economic impact that honey bees have in the United States. Then it discusses the existing errors in these studies’ methodologies and offers a preliminary model that incorporates the full economic effects of honey bees. It then offers some policy suggestions in order to better address the needs of honey ...


Three Essays On Modeling Biofuel Feedstock Supply, Wei Zhou Jan 2015

Three Essays On Modeling Biofuel Feedstock Supply, Wei Zhou

Graduate Theses and Dissertations

The general theme of this dissertation is modeling biofuel feedstock supply. All three essays focuses on different topics relating to the theme. The first essay considers supply of corn stover for a commercial production of a cellulosic ethanol plant. The economic trade-offs in determining the plant size under uncertain future corn stover yields and cellulosic ethanol prices are analyzed. We also estimate the impacts on optimal plant sizes under two payment schemes for corn stover procurement: plant pays for transportation cost and farmers pay for the transportation cost. My second essay analyzes the impact of ethanol mandates on corn prices ...


Implementing Green Roofs On Movie Theaters And Shopping Centers: Business Cases In Profitable Sustainability, Ryan J. Miller Jan 2014

Implementing Green Roofs On Movie Theaters And Shopping Centers: Business Cases In Profitable Sustainability, Ryan J. Miller

Pomona Senior Theses

This thesis presents the business case for installing green roofs on movie theaters and shopping centers. These businesses can then derive increased profits from the environmental benefits of reduced energy use and increased stormwater retention. After presenting the basic design and benefits of a green roof, the thesis develops stand-alone business plans for a movie theater and shopping center. The author finds that green roofs are a profitable sustainability solution for the commercial enterprise.


Alternative Approaches For Sharing Machinery, Labor, And Other Resources Among Small- And Medium-Sized Agricultural Producers, Greg Colson Jan 2008

Alternative Approaches For Sharing Machinery, Labor, And Other Resources Among Small- And Medium-Sized Agricultural Producers, Greg Colson

Retrospective Theses and Dissertations

As the U.S. agriculture industry continues to become increasingly concentrated, the viability of small- and medium-sized farms faced with diminishing profit margins per unit of output hinges in part on their ability to expand operations. In this study, the solution to this problem of taking advantage of economies of scale through farm-level resource sharing arrangements is considered. Through a two phase data collection procedure, Midwestern farmer groups engaged in resource sharing arrangements were identified and investigated through a case study approach. Evidence from the case studies suggest that sharing of equipment and labor can yield not only financial benefits ...


Essays On Fall Fertilizer Application, Mira Nurmakhanova Jan 2008

Essays On Fall Fertilizer Application, Mira Nurmakhanova

Retrospective Theses and Dissertations

Increased use of nitrogen fertilizer in agricultural production has contributed to increased food production but also contributed to elevated concentration levels of nitrates in groundwater and surface water. High concentration levels of nitrates in drinking water supplied from groundwater and surface water have become a public concern because of their risks to human health.;One way to reduce nitrogen losses is to develop and apply technologies that enable farmers to more accurately match the amount and timing of fertilizer application to crop growth needs. It is best to apply nitrogen as close as possible to when crop needs it most ...


Three Essays On Contract Farming In China, Jianhua Zhu Jan 2007

Three Essays On Contract Farming In China, Jianhua Zhu

Retrospective Theses and Dissertations

Contract farming in China has grown rapidly over the past 10 years. The first part of this dissertation examines the evolution of contract farming, and explores the incentives to engage in contract farming, preferred contract provisions, and contract performance from the perspective of both Chinese farmers and contracting firms. Firm and household perceptions of contracting are assessed using data obtained from village and firm level surveys. Farmers identify price stability and market access as the key advantages to contracts, while firms consider improved product quality as the primary incentive to use contracts.;In Part II, the survey data are used ...


Three Essays On Food Quality And Transaction Costs , Chengyan Yue Jan 2006

Three Essays On Food Quality And Transaction Costs , Chengyan Yue

Retrospective Theses and Dissertations

Product quality and product differentiation have become increasingly important to producers and policymakers for explaining consumer choice over food products. Consumers are often willing to pay large price premiums for products with preferred attributes. Heterogeneity in quality increases the diversity of goods for consumers and can improve welfare. However, variation in quality also leads to higher transaction costs for consumers, producers and policymakers because quality attributes are hard to identify precisely and vary when the state of the world changes. The first essay addresses the issue of food-quality attributes driven by protectionist policy that inhibits exchange between two countries. Technical ...


Micro-Level Econometric And Water-Quality Modeling: Simulation Of Nutrient Management Policy Effects , Christopher Sean Burkart Jan 2006

Micro-Level Econometric And Water-Quality Modeling: Simulation Of Nutrient Management Policy Effects , Christopher Sean Burkart

Retrospective Theses and Dissertations

Large surface areas of lakes and streams are impaired by nutrient contributions from agricultural nonpoint sources. This research develops a fully integrated economic and water quality model of an actual watershed to assess alternative nutrient abatement polities in terms of their economic efficiency and water quality effects. The policies examined include fertilizer taxes, application rate caps, uniform reductions, and a cap-and-trade fertilizer application right trading scheme. A micro-econometric field scale model of nutrient application is estimated using USDA Agricultural Resource Management Survey (ARMS) data combined with prices and spatially detailed soil data. Estimation results are interfaced with the Soil and ...


An Analysis Of The Iowan Angler's Fishing License Renewal Decision, Ryan R. French Jan 2006

An Analysis Of The Iowan Angler's Fishing License Renewal Decision, Ryan R. French

Retrospective Theses and Dissertations

The number of annual fishing licenses sold in Iowa has been in decline for two decades and has limited the amount of funds available to the Iowa Department of Natural Resources for fisheries management. The Iowa DNR is focused on reversing this trend through targeted marketing and efficient management of fishing resources. An analysis of Iowa anglers is performed with these goals in mind using past surveys and current customer data. The product of this analysis is a model which predicts whether a past customer will renew their license in the upcoming year. A logit model is developed using license ...


Essays On International Trade, Endogenous Quality And Invasive Species Risk , Anh Thuy Tu Jan 2005

Essays On International Trade, Endogenous Quality And Invasive Species Risk , Anh Thuy Tu

Retrospective Theses and Dissertations

This dissertation studies the relation between international trade and two issues that have become the active fields of economic research: the firms' quality decisions and the invasive species risk.;On the quality choice, the dissertation focuses on the impact of Voluntary Import Expansions (VIEs) on firms' quality decisions. I model a vertically differentiated international duopoly, with one firm in each country. A domestic and an exporting firm choose the quality of their goods and then compete in the domestic market. Both quantity and price conjectures are considered. The paper investigates the case where the government of the exporting country imposes ...


Investment In The Stock Market And Value-Added Agricultural Businesses As Portfolio Investment Alternatives To Farm Expansion, Joshua David Roe Jan 2005

Investment In The Stock Market And Value-Added Agricultural Businesses As Portfolio Investment Alternatives To Farm Expansion, Joshua David Roe

Retrospective Theses and Dissertations

In the past decade, farmers have increasingly invested in value-added agriculture. Analysis of these investments compared to farm expansion by farmers was conducted from a portfolio optimization standpoint. Farms with similar investment patterns were identified by cluster analysis. When individual farm characteristics were analyzed to determine how these attributes affected investment choices, clear influences were found. In general, value-added agricultural investments were found to be an efficient investment alternative to farm expansion. Because of their larger risk, stock market investments play a smaller role in an optimized producer portfolio.


Three Essays On Rural Economic Growth , Georgeanne Michael Artz Jan 2005

Three Essays On Rural Economic Growth , Georgeanne Michael Artz

Retrospective Theses and Dissertations

This dissertation is a collection of three papers, each analyzing a particular issue related to economic growth in rural America. The first paper explores the problem of defining rural and the implications for measuring rural growth. It discusses the sample selection problem inherent in using classification methods based on population that change over time. Fast growing rural areas grow out of their rural status, so using the most recent definition of rural in an analysis of growth excludes the most successful places. The findings demonstrate that average economic performance of the areas remaining rural significantly understates the true performance of ...


Three Essays On The Economics Of Innovation , Harun Bulut Jan 2005

Three Essays On The Economics Of Innovation , Harun Bulut

Retrospective Theses and Dissertations

We have identified three specific problems in the economics of innovation and addressed each of them in separate essays in this thesis.;Essay 1 revisits the problem of inefficient diversification efforts of firms in a R&D race setting (Dasgupta and Maskin, 1987)1 by taking into account the fact that firms have the option of trade secrecy in addition to patents in protecting their inventions. This essay is theoretical in nature as we use a game-theoretic modeling of firms' project and IP choices in a R&D race. We find that the availability of multiple IPR protection instruments can move the paths chosen by firms engaged in a R&D race towards the social optimum.;Essay 2 refers to the adoption and diffusion stages of the innovation process as we look at the economic effects of the introduction of Genetically Modified (GM) food in the European Union (EU) agricultural and food system. We develop a partial equilibrium modeling of European agro food sector and calibrate the model's parameters by using the EU data in year 2000. We find ...


A Statistical Regression Model To Determine Financial Cash Flow For Wind Energy Based On Tax Structure, Matthew Dae Joong Ritsema Jan 2004

A Statistical Regression Model To Determine Financial Cash Flow For Wind Energy Based On Tax Structure, Matthew Dae Joong Ritsema

Retrospective Theses and Dissertations

A financial cash flow for wind turbines is based on an energy entity's tax structure. Using statistical regression of various wind turbines and wind maps, a theoretical model for energy output was calculated. The turbines were separated by the rated size of the turbine. With the theoretical model, financial output was generated for four different types of tax structures. A total of eight test cases were simulated. Special consideration was given to the impact of Production Tax Credits (PTC) and Renewable Energy Production Incentives (REPI). The object is to determine what type of business and tax structure would have ...


The Food Chain Of Sheep And Policy Implications On The Sheep Sector In Syria In Highlight Of International Arrangements, Samir Grad Jan 2004

The Food Chain Of Sheep And Policy Implications On The Sheep Sector In Syria In Highlight Of International Arrangements, Samir Grad

Retrospective Theses and Dissertations

The sheep sector in Syria is considered as one of the most important sectors in animal production because it is the first source of meat, the second source of milk, and an export-oriented sector. Therefore, the need has emerged to study its supply chain in order to identify its weaknesses and bottlenecks and make suggestions for improvement. Accordingly, the theoretical background of food marketing is briefly presented including the functions and tools used by analyzing the marketing process. Hereby, the focus is on the approaches used by analyzing the food chains from various perspectives. In this context, the major actors ...


The Impact Of Improved Nutrition On Labor Productivity And Gdp Growth Rate In Low- And Middle-Income Countries, Majd Abdulla Jan 2004

The Impact Of Improved Nutrition On Labor Productivity And Gdp Growth Rate In Low- And Middle-Income Countries, Majd Abdulla

Retrospective Theses and Dissertations

This study examined the effects of nutrition on the growth rate of country economies over time. Previous studies on this topic have resulted in debates among researchers over how significant nutritional effects are on individual country economies. For this study, data were collected for four decades (1960s, 1970, 1980s, and 1990s) for 43 low- and middle-income countries. The data were analyzed to determine the effect of nutrition, represented by dietary energy supply (DES), on the growth rate of gross domestic product (GDP) per worker and on labor productivity. The research utilized ordinary least squares, instrumental variables, and random effects regressions ...


Insuring Uncertainty In Value-Added Agriculture: Ethanol, Nicholas David Paulson Jan 2004

Insuring Uncertainty In Value-Added Agriculture: Ethanol, Nicholas David Paulson

Retrospective Theses and Dissertations

A wide variety of insurance products are currently available for agricultural producers to insure against yield or price risks in the markets for the raw commodities they produce. Value-added enterprises, such as ethanol production, have become increasingly popular among farmers over the last decade; however, insurance against declines in the value-added portion of their crops is not yet available. This paper outlines the development of an insurance product aimed at corn producers who are members of an ethanol production cooperative. The product mimics the gross margin level of a typical ethanol production facility, and has the potential to provide producers ...


The Economic Potential Of Switchgrass As A Viable Biofuel Alternative, Jennifer E. Reutzel Jan 2004

The Economic Potential Of Switchgrass As A Viable Biofuel Alternative, Jennifer E. Reutzel

Retrospective Theses and Dissertations

To be commercially viable as a bioenergy feedstock, switchgrass must be cost-competitive. Switchgrass production and delivery costs are calculated for the Chariton Valley Switchgrass Biomass Project located in the Chariton Valley, Iowa. Sensitivity analyses are performed to determine which variables have the greatest impact on cost. Switchgrass production costs would require higher than expected market prices, and therefore various incentive payment options are considered. The incentive payments attempt to encapsulate the positive environmental attributes from the production of switchgrass as well as using switchgrass as a clean energy coal substitute. A modified CRP payment, carbon payment, and green tag payment ...


Land Preservation Decisions: Theoretical And Empirical Analysis , Shikha Marwah Jan 2004

Land Preservation Decisions: Theoretical And Empirical Analysis , Shikha Marwah

Retrospective Theses and Dissertations

There is a great concern that human actions are leading to increased rates of extinction of species. Ecologists have pointed out that the most important threat to wildlife comes from habitat alteration. The rapidly increasing human population and the resulting pressing demand for food and living space are pushing highly diverse natural areas into agriculture and other alternative uses. Recognizing this, the Federal agencies and private organizations, such as the Nature Conservancy, are becoming increasingly engaged in programs for conservation of species, where habitat restoration is an important component. However, this conservation is costly and there is uncertainty in the ...


Panel Econometric Evidence Of Chinese Agricultural Household Behavior In The Later 1990s: Production Efficiency, Size Effects And Human Mobility , Zhuo Chen Jan 2004

Panel Econometric Evidence Of Chinese Agricultural Household Behavior In The Later 1990s: Production Efficiency, Size Effects And Human Mobility , Zhuo Chen

Retrospective Theses and Dissertations

The dissertation consists of three essays that analyze production efficiency, size effects and human mobility using a panel of 591 Chinese agricultural households in the later 1990s.;The first essay estimates technical efficiency through the framework of a translog stochastic production frontier with a behavioral inefficiency component. The results reveal a decreasing trend of output elasticities with respect to labor and fertilizer. The marginal effects of inefficiency terms show significant output gains by eliminating land fragmentation, improving access to education in rural area, and promoting specialization and mechanization.;The second essay examines land heterogeneities and the empirical inverse relationship in ...


Investment Analysis Of Deferring A Farmer Owned Ethanol Plant: Using Real Options, Ramanathan Shunmugavelu Jan 2003

Investment Analysis Of Deferring A Farmer Owned Ethanol Plant: Using Real Options, Ramanathan Shunmugavelu

Retrospective Theses and Dissertations

A farmers owned value-added (FOVA) business is often subject to changes in the political situations. So an investment analysis tool that incorporates uncertainty, such as real options is more appropriate. Application of real options is limited in FOVA businesses. In this thesis, the concept of real options is applied under the framework of a farmer owned ethanol plant. The impact of changes in the policy or political situations on ethanol industry is well known. Farmer investors that are currently interested in investing in an ethanol plant should decide whether it is worthwhile to invest now or wait for a year ...


A Stochastic Model Of Maize Gene Dispersal, David G. Ripplinger Jan 2003

A Stochastic Model Of Maize Gene Dispersal, David G. Ripplinger

Retrospective Theses and Dissertations

The spatial distribution of maize genes is predicted using a two dimensional Lagrangian stochastic (LS) model that meets sub-inertial and well-mixed conditions. Using wind data from central Iowa, a Weibull distribution is fit. From this distribution, a series of Monte Carlo simulations are run using the LS model in three forms. The final two forms of the model are based on USDA regulations for the production of pharmaceutical producing corn, demonstrating the model's suitability for analyzing the risk of transgene dispersal in maize. Special considerations are given to the large size of maize pollen, the likelihood of pollen seepage ...


Second Moment Characterization Of Agricultural Export And Income Projection Models, Andrew Dean Miller Jan 2003

Second Moment Characterization Of Agricultural Export And Income Projection Models, Andrew Dean Miller

Retrospective Theses and Dissertations

Agricultural outlook baseline projections published by FAPRI, USDA and the OECD are intended as policy analysis tools. It is shown that projections have been used as forecasts. Therefore, users of baseline projections need information about the past performance of baseline projections. This thesis measures the projection errors of baseline projections using RMSE and MAPE and assesses the ability of models to predict directional movements. The baseline model results are compared to corresponding results of naive models. For projection errors, a mixed model is used to estimate the mean bias and confidence intervals about the mean. Projections of corn, soybean, wheat ...


Factors Affecting Symbolic And Use Adoption Of Local Foods For Consumers In Black Hawk County, Iowa, Erin M. Tegtmeier Jan 2003

Factors Affecting Symbolic And Use Adoption Of Local Foods For Consumers In Black Hawk County, Iowa, Erin M. Tegtmeier

Retrospective Theses and Dissertations

A local food system may be an alternative to the increasingly globalized and concentrated food market and a means to augment the availability of fresh foods, create economically viable options for farmers and enhance the health of local ecosystems. Consumers are a vital component of these systems. Insight into the decision-making process surrounding the purchase of local foods can aid in efforts to build thriving local food systems. Studies on consumer attitudes show that, in general, consumers are aware and supportive of local foods. Abstract or civic factors, such as concern for the environment or food safety, are often identified ...


An Economic Perspective On Iowa Farm Diversification In The Twentieth Century, Matthew Edward Miller Jan 2003

An Economic Perspective On Iowa Farm Diversification In The Twentieth Century, Matthew Edward Miller

Retrospective Theses and Dissertations

The thesis examines farm-level diversification in Iowa over the past century. Economic theory is employed to propose explanations for observed trends in diversification. The hypothesis says that agricultural production technology has been the driving force behind the emergence of large, highly specialized farms in Iowa. Applications from portfolio theory, the theory of the farm, and agronomics are also utilized to flesh out the theory section. Two indexes, entropy and the Hirschman-Herfindahl index, are constructed using production and price data from the Census of Agriculture. The indices show diversification as relatively constant from 1885 to 1930, after which, a strong specialization ...


Identifying The Driving Forces Of Rural Economic Growth: The Impact Of Intellectual Spillovers, Technology, And Amenities On Employment Growth In The Us Midwest , Daniel Charles Monchuk Jan 2003

Identifying The Driving Forces Of Rural Economic Growth: The Impact Of Intellectual Spillovers, Technology, And Amenities On Employment Growth In The Us Midwest , Daniel Charles Monchuk

Retrospective Theses and Dissertations

This dissertation examines a number of issues related to economic growth in rural regions. The major themes explored are the roles of spatial technological externalities in the creation of new knowledge, the impacts of technology and technology spillovers on non-farm employment growth, and the role of amenities influencing non-farm employment growth. The theoretical model examines the interaction between rural and urban areas in an overlapping generations model allowing migration of high skill workers. The major theoretical conclusions reached suggests: (1) if technology spillovers exist in the urban market then high skill individuals will seek employment in the urban area where ...


Contract Design In Soybean Production, Nandini Ramesh Jan 2002

Contract Design In Soybean Production, Nandini Ramesh

Retrospective Theses and Dissertations

Although there is considerable interest in component pricing of soybeans from both the industry and the academia, it is not commonly observed in the soybean industry. In this thesis, the Principal Agent model is used to design a contract between a processor and grower. The processor provides incentives to growers to produce soybeans with higher components (protein and oil) in them. Under the assumption that growers are risk neutral, a contract is designed where the grower faces all the risk in the production of components. The contract also compensates the grower for the yield drag as a result of production ...