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on Agricultural Economics |
Issue of 2009‒01‒03
24 papers chosen by |
By: | Kassie, Menale (Department of Economics, School of Business, Economics and Law, Göteborg University); Zikhali, Precious (Department of Economics, School of Business, Economics and Law, Göteborg University); Manjur, Kebede (Tigray Agricultural Research Institute); Edwards, Sue (Institute for Sustainable Development,) |
Abstract: | In the wake of resource constraints faced by farmers in developing countries in using external farm inputs, sustainable agricultural production practices that rely on local or farm renewable resources present desirable options for enhancing agricultural productivity. In this paper we use plot-level data from the semi-arid region of Ethiopia, Tigray, to investigate the factors influencing farmers' decisions to adopt sustainable agricultural production practices, with a particular focus on conservation tillage and compost. While there is heterogeneity with regards to factors influencing the choice to use either practice, results from a multinomial logit analysis underscore the importance of both plot and household characteristics on adoption decisions. In particular we find that poverty, and access to information, among other factors, impact the choice of farming practices significantly. We also find evidence that the impact of gender on technology adoption is technology specific while the significance of plot characteristics indicate the decision to adopt specific technologies is location-specific. Furthermore the use of stochastic dominance analysis supports the contention that sustainable farming practices enhance productivity -they even prove to be superior to the use of chemical fertilizers- justifying the need to investigate factors that influence adoption of these practices and use this knowledge to formulate policies that encourage adoption.<p> |
Keywords: | Sustainable agriculture; Adoption; Productivity; Compost; Conservation tillage; Ethiopia |
JEL: | Q12 Q16 Q24 |
Date: | 2008–12–16 |
URL: | http://d.repec.org/n?u=RePEc:hhs:gunwpe:0335&r=agr |
By: | Steven Haggblade; T.S. Jayne; David L. Tschirley; Steven Longabaugh |
Abstract: | This working paper explores the prospects for regional maize trade in helping to stabilize food availability and prices in Zambia. It reviews these general prospects within the maize economy of southern Africa. Given the important regional differences in Zambia’s food economy, it explores spatial differences in national food production, consumption and marketed surpluses. It also evaluates the impact of regional maize trade on price stability and food security in different parts of Zambia. The empirical evidence from Zambia, summarized in this paper, suggests that both consumers and farmers stand to benefit from the reduced price volatility that results from opening borders to regional trade in food staples. |
Keywords: | maize, trade, Africa, Zambia |
JEL: | Q18 |
Date: | 2008–11 |
URL: | http://d.repec.org/n?u=RePEc:msu:icpwrk:zm-fsrp-wp-35&r=agr |
By: | Kassie, Menale (Department of Economics, School of Business, Economics and Law, Göteborg University); Zikhali, Precious (Department of Economics, School of Business, Economics and Law, Göteborg University); Pender, John (International Food Policy Research Institute, (IFPRI)); Köhlin, Gunnar (Department of Economics, School of Business, Economics and Law, Göteborg University) |
Abstract: | Organic farming practices, in as far as they rely on local or farm renewable resources, present desirable options for enhancing agricultural productivity for resource-constrained farmers in developing countries. In this paper we use plot-level data from semi-arid area of Ethiopia to investigate the impact of organic farming practices on crop productivity, with a particular focus on conservation tillage. Specifically we seek to investigate whether conservation tillage results in more or less productivity gains than chemical fertilizer. Our results reveal a clear superiority of organic farming practices over chemical fertilizers in enhancing crop productivity. Thus our results underscore the importance of encouraging resource-constrained farmers in developing countries to adopt organic farming practices, especially since they enable farmers to reduce production costs, provide environmental benefits, and as our results confirm, enhance crop productivity.<p> |
Keywords: | Conservation tillage; Chemical fertilizer; Crop productivity; Matched observations; Ethiopia |
JEL: | C21 Q12 Q15 Q16 Q24 |
Date: | 2008–12–16 |
URL: | http://d.repec.org/n?u=RePEc:hhs:gunwpe:0334&r=agr |
By: | Avalos-Sartorio, Beatriz; Blackman, Allen (Resources for the Future) |
Abstract: | Economic policies that boost the return to mixed agroforesty, thereby creating financial incentives for land managers to favor these systems over less environmentally friendly land uses, could, in theory, have ancillary environmental benefits. This paper analyses primary and secondary data to determine whether a voluntary price support program for Mexican coffee—mostly grown in shaded systems that supply important ecosystem services—has had such “win-win” benefits by stemming rampant land-use change in the coffee sector. We find that although the program attracted the types of growers associated with land-use change, it attracted only a relatively small number of them, did not target growing areas hardest hit by conversion to other land uses, and provided subsidies that were probably too small to affect land-use decisions. These results raise serious questions about the ability of a mixed agroforestry price support program with a modest price floor to have a significant conservation impact. |
Keywords: | mixed agroforestry, shade-grown coffee, Mexico, price supports |
JEL: | Q23 Q56 Q57 O13 |
Date: | 2008–12–22 |
URL: | http://d.repec.org/n?u=RePEc:rff:dpaper:dp-08-48&r=agr |
By: | KAMINSKI Jonathan; THOMAS Alban |
Date: | 2009–01 |
URL: | http://d.repec.org/n?u=RePEc:ler:wpaper:09.01.277&r=agr |
By: | Frank J. Dooley (Department of Agricultural Economics, College of Agriculture, Purdue University) |
Abstract: | The rapid expansion of the ethanol industry in Indiana has saturated the local market for the principal co-product, distillers grains with solubles (DDGS). In the near term, Indiana’s livestock industry can be expected to consume up to 895,000 tons of DDGS per year. But given production of 2.7 million tons, Indiana’s ethanol producers will rely on railroads and barges to ship excess production to out-of-state destinations. Livestock producers will have a ready access to DDGS across the state. |
Keywords: | Staff market potential, distillers grains, Indiana, livestock |
JEL: | Q10 Q13 |
Date: | 2008 |
URL: | http://d.repec.org/n?u=RePEc:pae:wpaper:08-11&r=agr |
By: | Qiujie Zheng; C. Richard Shumway (School of Economic Sciences, Washington State University) |
Abstract: | Biofuels, as alternative transportation fuels, are now being used globally. Taking advantage of in-state feedstock supply is an efficient way to stimulate in-state biofuel industries and the local economy. This paper uses several models to estimate supply equations for major biofuel feedstock crops in Washington. We estimate expected utility maximization models, expected profit maximization models, and several pragmatic models. We examine the comparative statics results of the models, and use the results to draw important implications for Washington policy makers and for farmers who are considering production of biofuel feedstocks. |
Keywords: | biofuel feedstock, output uncertainty, price uncertainty, profit maximization, supply |
Date: | 2008–12 |
URL: | http://d.repec.org/n?u=RePEc:wsu:wpaper:shumway-9&r=agr |
By: | Valerie Kelly; David L. Tschirley |
Abstract: | This Policy Brief summarizes evidence reported in a recent study on the links between seed cotton market structures and selected cotton sector performance indicators in nine African countries (Tschirley et al. 2008). The purpose of the study is to contribute to better design and implementation of cotton sector reforms by building a reliable, broad assessment of cotton sector performance from detailed empirical information collected and analyzed by independent researchers and cotton sector experts. |
Keywords: | cotton, seed, market, Africa |
JEL: | Q18 |
Date: | 2008–11 |
URL: | http://d.repec.org/n?u=RePEc:msu:icpbrf:wacip_pb002&r=agr |
By: | Tristan D. Skolrud; Erik O'Donoghue; C. Richard Shumway; Almuhanad Melhim (School of Economic Sciences, Washington State University) |
Abstract: | Growth and diversification patterns of size cohorts in four Washington state agricultural industries between the 1992 and 2002 agricultural censuses are examined. Three industries (wheat, apples, and beef) show similar growth patterns. Two (wheat and apples) show similar diversification patterns. Dairy is unique on both measures. |
Keywords: | opportunistic agricultural, diversification patterns, dairy |
JEL: | Q12 |
Date: | 2008–12 |
URL: | http://d.repec.org/n?u=RePEc:wsu:wpaper:shumway-8&r=agr |
By: | Cory G. Walters; C. Richard Shumway; Hayley H. Chouinard; Philip R. Wandschneider (School of Economic Sciences, Washington State University) |
Abstract: | Opportunistic behavior in crop insurance can arise due to asymmetric information between producers and the Federal Crop Insurance Corporation. Producers who insure fields using transitional yields based on county average yields or who select options such as buy-up coverage or revenue insurance may increase their return from crop insurance. Using field-level crop insurance contract data for several crops in five growing regions, we find evidence that producers can profit from using buy-up coverage, revenue insurance, and transitional yields and that the level of producer opportunism is crop but not necessarily land-quality specific and is greater due to premium subsidization. |
Keywords: | opportunistic behavior, crop insurance, buy-up, revenue, transitional yields |
JEL: | Q18 |
Date: | 2008–08 |
URL: | http://d.repec.org/n?u=RePEc:wsu:wpaper:shumway-7&r=agr |
By: | Roman Keeney; Thomas W. Hertel (Department of Agricultural Economics, College of Agriculture, Purdue University) |
Abstract: | We examine the determinants of own-price output supply response in policy models, focusing primarily on the OECD-PEM equilibrium displacement model. Reviewing expert assessments and econometric literature estimates we find that there is evidence to both support and challenge the relatively high supply response of a model like the OECD-PEM. We also consider possible avenues of reconciliation between evidence that supports and challenges the assumed supply response in the OECD-PEM model. Our analysis of supply response in the OECD-PEM case and from reviewing literature leads us to recommend that future econometric investigation be focused on the role of farm household owned resource mobility as it contributes to agricultural supply response. |
Keywords: | Supply response, Yield elasticity, Policy models |
JEL: | Q11 Q12 Q18 |
Date: | 2008 |
URL: | http://d.repec.org/n?u=RePEc:pae:wpaper:08-13&r=agr |
By: | Almuhanad Melhim; Erik J. O'Donoghue; C. Richard Shumway (School of Economic Sciences, Washington State University) |
Abstract: | Recent consolidation in agriculture has shifted production toward fewer but larger farms, reshaping business relationships between farmers, processors, input suppliers, and local communities. We analyze growth and diversification of U.S. corn, wheat, apple, and beef, farms by examining longitudinal changes in ten size cohorts through three successive censuses. We fail to reject Gibrat’s law in apple and wheat industries and the mean reversion hypothesis in beef and corn industries. Apple and wheat farms diversify over time. Findings suggest that scale economies diminish for large farms across all four industries and scope economies dominate scale economies for large apple and wheat farms. |
Keywords: | firm growth, diversification, scale economies, scope economies, Gibrat’s law, longitudinal data |
JEL: | Q12 |
Date: | 2008–04 |
URL: | http://d.repec.org/n?u=RePEc:wsu:wpaper:shumway-3&r=agr |
By: | Yucan Liu; C. Richard Shumway; Robert Rosenman; V. Eldon Ball |
Abstract: | Dynamic effects of health and inter-state and inter-industry knowledge spillovers, total factor productivity (TFP) growth and convergence in U.S. agriculture are examined using recently developed procedures for panel data and a growth accounting model. Strong evidence is found to support the hypothesis that TFP converges to a steady-state. Health care supply in rural areas and research spillovers from other states and from nonagricultural sectors are found to have significant impacts on the productivity growth rate both in the short-run and long-run. These results suggest richer opportunities for policymakers to enhance productivity growth. |
Keywords: | convergence, growth, pooled mean group estimator, total factor productivity |
JEL: | O30 D24 |
Date: | 2008–01 |
URL: | http://d.repec.org/n?u=RePEc:wsu:wpaper:shumway-2&r=agr |
By: | Angel Bujosa Bestard (Centre de Recerca Econòmica (UIB · Sa Nostra)); Antoni Riera Font (Centre de Recerca Econòmica (UIB · Sa Nostra)) |
Abstract: | The accuracy of environmental valuation studies relies, to a great extent, on the suitability of the proxy measures used to capture individuals’ preferences. While important advances have been achieved in last years concerning the characterization of the physical background in which recreational choices are made, Travel Cost Method applications have failed to consider the heterogeneity of landscape and the spatial configuration of land use. This paper presents an empirical application to forest recreation in Mallorca (Spain), implementing a random parameter logit model to evaluate —in terms of goodness-of-fit, model predictions and welfare measurements— the effects of environmental diversity on the recreational site-choice process. |
Keywords: | Travel Cost Method, random parameter logit, recreation demand, environmental diversity, forests |
Date: | 2008 |
URL: | http://d.repec.org/n?u=RePEc:pdm:wpaper:2008/5&r=agr |
By: | Gundersen, Craig; Kreider, Brent |
Abstract: | Previous research has estimated that food insecure children are more likely to suffer from a wide array of negative health outcomes than food secure children, leading many to claim that alleviating food insecurity would lead to better health outcomes. Identifying the causal impacts is problematic, however, given endogenous selection into food security status and potential classification errors in measuring true food security status. Using recently developed nonparametric bounding methods and data from the 2001-2006 National Health and Nutritional Examination Survey (NHANES), we assess what can be identified about the effects of food insecurity on child health outcomes in the presence of nonrandom selection and nonclassical measurement error. Under relatively weak monotonicity assumptions, we can identify that food security has a statistically significant positive impact on good general health and being a healthy weight. Our work suggests that previous research has more likely underestimated than overestimated the causal impacts on health. |
Keywords: | food insecurity; health outcomes; nonclassical measurement error; nonparametric bounds; average treatment effect |
JEL: | I1 I3 |
Date: | 2008–12–13 |
URL: | http://d.repec.org/n?u=RePEc:isu:genres:13008&r=agr |
By: | Olson, Kent D.; Badibanga, Thaddee; DiFonzo, Christina |
Abstract: | In response to the introduction and rapid spread of soybean aphid, farmers in the Upper Midwest were surveyed about their treatment of and knowledge about soybean aphids for crop years 2004, 2005, 2006, and 2007. Overall, the farmers showed a fairly good understanding of soybean aphids and their impact on soybeans. Over 80% said soybean aphids could be treated and repopulate in the same crop year. For 2004-2006, at least 75% of the farmers said aphids damaged their soybeans by sucking sap. However this percentage dropped to 59% for 2007 with a greater percentage pointing at a combination of damage methods. This lower percentage for 2007 may be due to a broader, randomly selected sample of farmers who received the surveys by mail versus farmers who attended meetings in the first three years. However, even though fewer seemed to have a clear understanding of how aphids damage soybeans, other measures indicate a stable or improved understanding of soybean aphid biology and control. Over 70% said the frequency with which aphids should be treated for profitable control depends on aphid counts, weather conditions and plant growth stage. About a third of the farmers believed that aphids inflict the most damage during early flowering through pod set (R1-R3); however, about a third also thought aphids could inflict the most damage at any stage. Over half the farmers considered the lowest aphid density for profitable aphid control to be 250 aphids per plant. Over 80% said scouting reports were very important for making a decision to treat for aphids; over half the farmers said plant growth stage was also very important. |
Keywords: | Crop Production/Industries, |
Date: | 2008–12 |
URL: | http://d.repec.org/n?u=RePEc:ags:umaesp:45803&r=agr |
By: | Lazarus, William F, |
Abstract: | Production costs and breakeven prices were calculated for four energy crops plus corn stover. The energy crop breakeven prices were calculated under two different scenarios regarding land costs and the opportunity costs of not utilizing the land for some other competing land use. One scenario is that the competing land use is pasture. The other is that the energy crops would compete with grain crops on more expensive land, and would need to provide a return over land costs equal to returns on the grain crops. Corn stover would be the cheapest of the energy biomass sources considered, at $50/ton to cover the additional machinery costs to shred, rake, bale, and transport 25 miles to a processing plant. Aside from stover, a grassland crop under high fertilization with a 4-ton yield has the lowest cost at $77/ton of dry matter. A grassland crop under low fertilization with a 2-ton yield but a longer stand life has the highest cost at $110/ton. Hybrid poplar comes in at $81/ton. Willow is at an early stage of development in Minnesota, but it would be the cheapest energy crop at $72/ton if it achieves a 5-ton yield with a 23-year stand life that has been reported in New York. These costs are based on the pasture land rental rate of $40/acre. The more expensive grain crop land translates directly into higher energy crop breakeven prices which are also presented in the paper. |
Keywords: | Crop Production/Industries, |
Date: | 2008–12 |
URL: | http://d.repec.org/n?u=RePEc:ags:umaesp:45655&r=agr |
By: | Hayes, Dermot J.; Klopfenstein, Terry J.; Erickson, Galen E.; Bremer, Virgil R.; Schingoethe, David J.; Stein, Hans H.; Bregendahl, Kristjan; Fox, John A.; Paulson, Nicholas D.; Dahlke, Garland; Lawrence, John D.; Dooley, Frank J.; Martens, Bobby J.; Shurson, Jerry; Alghamdi, Abdorrahman S. |
Abstract: | This book brings together in one publication the latest information and research findings of internationally renowned experts to help market participants understand how best to utilize distillers grains both in the U.S. domestic market and in international export markets. The book discusses how to optimize distillers dried grains with solubles (DDGS) to best suit the needs of beef cattle, dairy cattle, swine, and poultry, and how each species can best take advantage of current and improved DDGS products. The book also lays out export opportunities for DDGS and describes challenges and technological hurdles that need to be resolved for better nutritional value and best storage and transport practices. |
Keywords: | distillers grains, distillers dried grains with solubles, DDGS, livestock and poultry feed |
Date: | 2008–12–23 |
URL: | http://d.repec.org/n?u=RePEc:isu:genres:13009&r=agr |
By: | Clark P. Bishop; C. Richard Shumway; Philip R. Wandschneider (School of Economic Sciences, Washington State University) |
Abstract: | Anaerobic digestion technology addresses environmental issues of waste disposal and greenhouse gas emission reduction. This paper examines attitudes toward adoption of this conservation technology on dairy farms. To specify an appropriate dependent variable without a large number of adopters, an ordered probit model is constructed. The empirical analysis uses data from a 2006 survey of Northwest dairy farms. Aggregate variables are constructed based on behavioral economics and conservation adoption literature. Variables include private and social costs, social motives, capacity, innovation receptivity, and opportunity costs, most of which are found to be highly related to the decision to seriously consider adoption. |
Keywords: | adoption, anaerobic digestion, behavioral economics, conservation, dairy, environment, meta-utility, Northwest |
JEL: | Q55 Q53 Q54 |
Date: | 2008–08 |
URL: | http://d.repec.org/n?u=RePEc:wsu:wpaper:shumway-6&r=agr |
By: | Yucan Liu; C. Richard Shumway (School of Economic Sciences, Washington State University) |
Abstract: | The hypothesis of induced innovation is tested for U.S. agriculture using a high-quality state-level panel data set and three disparate testing techniques – time series, direct econometric, and nonparametric. We find little support for the hypothesis. That conclusion is robust across testing techniques. However, as with all empirical tests of this hypothesis conducted to date, ours focus only on the demand side of the hypothesis. The hypothesis could have been rejected simply because the marginal cost of developing and implementing input-saving technologies for the relatively expensive inputs is greater than for the relatively cheap inputs. |
Keywords: | econometric, induced innovation, nonparametric, time series, 2-stage CES |
Date: | 2008–05 |
URL: | http://d.repec.org/n?u=RePEc:wsu:wpaper:shumway-1&r=agr |
By: | Yucan Liu; C. Richard Shumway (School of Economic Sciences, Washington State University) |
Abstract: | The hypothesis of induced innovation has been empirically tested in many ways, using a wide variety of data and test periods for many industries in many countries. However, each test has maintained the hypothesis that the relative marginal cost of developing and implementing technologies that save one input is the same as for any other input. Lacking data on development and implementation costs of input-saving technologies, we develop and use a nonparametric procedure to estimate relative differences required for technical change in U.S. agriculture to be consistent with the induced innovation hypothesis. |
Keywords: | induced innovation, marginal cost, nonparametric |
JEL: | O30 D24 |
Date: | 2008–06 |
URL: | http://d.repec.org/n?u=RePEc:wsu:wpaper:shumway-4&r=agr |
By: | Marcos Vera-Hernández (Institute for Fiscal Studies); Aida Galiano (Universidad de Zaragoza) |
Abstract: | This paper investigates the effect of health shocks on household consumption and child nutrition. Using longitudinal data from rural Colombia we find that several items of household consumption, including medical expenditure, food consumption, and total consumption, increase following a recent illness event of an adult usually active in the labour market. In contrast to this, we find that girls¿ weight is negatively affected, as a consequence of the same illness event. The results on nutrition present an interesting gender bias, since we do not find any evidence that boys¿ nutritional status deteriorates. Our conclusion is that households make difficult intrahousehold choices when an illness shock hit them. The results have implications for the literature on testing for full insurance because it usually relies on household consumption net of medical expenditures as a measure of welfare. This fact shows that this literature might has underestimated the effects of health shocks on welfare. Este artículo investiga los efectos de los shock de salud sobre el consumo de los hogares y la nutrición infantil. A partir de una base de datos longitudinal que corresponde a datos del área rural de Colombia encontramos que varios elementos del consumo de los hogares, incluidos gastos médicos, consumo de alimentos y consumo total del hogar, aumentan después de que una reciente enfermedad afecte a un adulto del hogar activo en el mercado de trabajo. En contraposición a este resultado, encontramos que la nutrición de los niños se ve negativamente afectada. En concreto el peso de las niñas se reduce tras este shock de salud. Este resultado sobre nutrición presenta un interesante sesgo de género, ya que no encontramos evidencia de un deterioro nutricional en los niños. Nuestra conclusión es que los hogares tienen difícil elecciones dentro de los hogares cuando un shock de salud les sacude. Este resultado tiene implicaciones para la literatura que prueba la cobertura total de los hogares ya que esta atiende únicamente al consumo de los hogares, neto de los gastos médicos, como medida de bienestar. Este hecho muestra que esta literatura podría estar subestimando los efectos de los shock de salud sobre el bienestar de los hogares. |
Keywords: | Riesgo compartido, Nutrición infantil, Consumo del hogar, Shock de salud. Risk sharing, Child nutrition, Household Consumption, Intrahousehold, Health Shocks. |
JEL: | C23 C81 D13 |
Date: | 2008–12 |
URL: | http://d.repec.org/n?u=RePEc:ivi:wpasec:2008-14&r=agr |
By: | Skander Ben Abdallah; Pierre Lasserre |
Abstract: | We use a real option approach to determine optimally when a social planner has to stop or resume logging in situations where an endangered species relies on forest habitat for its survival, and that habitat evolves stochastically. The model incorporates economic, ecological and social features, and is calibrated to generate an optimal forest management rule that balances the benefits from commercial forest exploitation with the risks of extinction facing the endangered species. For the reasonable parameters used in our application to the Rangifer tarandus caribou, an endangered species in Central Labrador (Canada), the policy of banning logging temporarily is quite attractive as it does not require long banning periods while it drastically reduces the extinction risk and increases forest value. <P>Nous utilisons la méthode des options réelles pour déterminer quand un planificateur social doit interrompre ou reprendre l’exploitation d’une forêt, lorsque celle-ci constitue l’habitat stochastique d’une espèce menacée d’extinction. Le modèle présente des aspects économiques, écologiques et sociaux; il établit une règle optimale de gestion forestière qui fait l’arbitrage entre les bénéfices commerciaux de l’exploitation forestière et les risques d’extinction de l’espèce. Pour des paramètres correspondant au cas du Rangifer tarandus caribou, une espèce du centre du Labrador (Canada) menacée d’extinction, la politique optimale d’interruption et reprise de l’exploitation forestière est attractive; elle n’exige pas de longs arrêts dans l’exploitation, alors qu’elle réduit significativement le risque d’extinction et augmente la valeur de la forêt. |
Keywords: | real options, biodiversity, endangered species, extinction, forestry., options réelles, biodiversité, extinction, espèces menacées, aménagement forestier. |
JEL: | C61 C63 D81 Q23 Q28 |
Date: | 2008–12–01 |
URL: | http://d.repec.org/n?u=RePEc:cir:cirwor:2008s-30&r=agr |
By: | Almuhanad Melhim; Erik J. O'Donoghue; C. Richard Shumway (School of Economic Sciences, Washington State University) |
Abstract: | We analyze growth and diversification of U.S. dairy farms by examining changes in ten size cohorts and new entrants through three successive censuses. We reject Gibrat’s law and the mean reversion hypothesis of growth. Growth rates appear bimodal where the smallest and largest farm cohorts grow fastest. All cohorts diversify but the largest farms do not diversify as rapidly as medium-sized farms. New entrants are generally large, and they diversify more rapidly than comparably-sized incumbents. These data suggest that scale economies persist even for the largest cohort of U.S. dairy farms and scale economies dominate scope economies for large farms. |
Keywords: | : census, dairy, diversification, growth, scale, scope |
JEL: | Q12 |
Date: | 2008–07 |
URL: | http://d.repec.org/n?u=RePEc:wsu:wpaper:shumway-5&r=agr |