From Microlevel Decisions to Landscape Changes: An Assessment of Agricultural Conservation Policies

The growth in conservation programs has created a need for modeling frameworks capable of measuring microlevel behavioral responses and macrolevel landscape changes. This paper presents an empirical model that predicts farmers' production practices and the resulting levels of agricultural runoffs at more than 42,000 agricultural sites in the upper-Mississippi river basin under alternative conservation policies. Results suggest that payments for conservation tillage and crop rotations increase the use of these conservation practices. However, the acreage response is inelastic and the programs are not likely to be cost effective on their own for addressing hypoxia problem in the Gulf of Mexico.     

Evaluating the Effect of Conservation Policies on Agricultural Land Use: A Site-specific Modeling Approach

This study evaluates quantitatively the effect of three policies (payments for cropland retirement, fertilizer use taxes and payments for crop rotations) on agricultural land use in the upper Mississippi River basin. This is done by estimating two logit models of land use decisions using data from the 1982, 1987,1992 and 1997 Natural Resource Inventories. The models predict farmers' crop choice, crop rotation and participation in the Conservation Reserve Program (CRP) at more than 48,000 Natural Resource Inventories sites under each of the three policies. Results suggest that an increase in the CRP rental rates would significantly increase the CRP acreage, but most of the acreage increase would come initially from less fertilizer‐intensive crops. In contrast, a fertilizer use tax would significantly reduce acreage planted to more fertilizer‐intensive crops, and thus would likely be cost effective for reducing agricultural chemical use and pollution. Although an incentive payment for a corn‐soybean rotation would raise acreage of this rotation and reduce the acreage of continuous corn, the acreage response is in general quite inelastic. Cette étude évalue quantitativement les effets rovoqués par les trois politiques (paiements pour le retrait des terres cultivables, taxes sur l'utilisation d'engrais et paiements pour l'alternance des cultures) sur les terres agricoles du bassin supérieur du Mississipi. Ceci est obtenu en évaluant deux modéles logit des décisions sur l'utilisation des terres provenant des données des «Natural Resource Inventories» de 1982, 1987, 1992 et 1997. Les modéles prédisent le choix des cultures des agriculteurs, l'alternance des cultures et la participation du «Conservation Reserve Program (CRP)» dans plus de 48 000 Natural Resource Inventories dans le cadre de chacune des trois politiques. Les résultats suggérent qu'une augmentation des taux de location du CRP accroisse de maniére significative la surface de CRP, mais la majeure partie de cet accroissement de surface provenaient initialement de cultures moins intensives sans engrais. Cependant, l'utilisation d'une taxe sur l'utilisation d'engrais pouvait réduire de maniére significative la surface plantée avec des récoltes intensives utilisant plus d'engrais, et ainsi ce serait sans doute plus économique pour réduire la pollution et l'utilisation de produits chimiques en agriculture. Bien que des paiements incitatifs à l'alternance maïs‐soja réduisent la surface d'une culture continue de maïs et augmentaient la surface de l'alternance maïs‐soja, les résultats aux transformations des surfaces des terres seraient tout à fait rigides.     

Asymmetric technological distance measure based on language model

This article introduces a novel technological distance measure between companies based on their patent portfolios. We describe the technological position or characteristics of companies by applying the framework of language modelling technique in information retrieval on their patent portfolios. The proposed novel approach is an asymmetric measure and better captures the technological characteristic of a company and hence is a more accurate distance measure.     

Retracted: Dynamics of Unclosed Triangles in Alliance Networks: Disappearance of Brokerage Positions and Performance Consequences

We depart from previous research on brokerage advantages in interorganizational networks by shifting focus to the dynamics of brokerage positions. We investigate causes of the disappearance of these positions and its influence on organizational performance. Using a subnetwork consisting of a broker and its two partners as the unit of analysis, we postulate that the brokerage position disappears either when the two partners develop ties or when the ties between the broker and the partners dissolve. We predict that the patterns of interactions in which this subnetwork is embedded exert multilevel influences on the disappearance, and that embedded structures promoting persistence constrain brokerage advantages. Our analysis of codeshare alliance data in the global airline industry supports the theory and demonstrates that the persistence of brokerage positions decreases broker performance. The findings explain why brokerage positions rarely persist and why the persistence of brokerage positions does not benefit brokers.     

On the computability of quasi-transitive binary social choice rules in an infinite society and the halting problem

This paper investigates the computability problem of the existence of a vetoer and an oligarchy for quasi-transitive binary social choice rules (Mas-Colell and Sonnenschein in Rev Econ Stud 39:185–192, 1972) in a society with an infinite number of individuals (infinite society) according to the computable calculus (or computable analysis) by Aberth (Computable analysis, McGraw-Hill, New York, 1980; Computable calculus, Academic Press, Dublin, 2001). We will show the following results. The problem whether a quasi-transitive binary social choice rule which satisfies Pareto principle and independence of irrelevant alternatives (IIA) has a vetoer or has no vetoer in an infinite society is a nonsolvable problem, that is, there exists no ideal computer program for a quasi-transitive binary social choice rule which satisfies Pareto principle and IIA that decides whether it has a vetoer or has no vetoer. And it is equivalent to nonsolvability of the halting problem. We also show that if for any quasi-transitive binary social choice rule there exists an oligarchy in an infinite society, whether it is finite or infinite is a nonsolvable problem. A vetoer is an individual such that if he strictly prefers an alternative to another alternative, then the society prefers the former to the latter or is indifferent between them regardless of the preferences of other individuals, and an oligarchy is the minimal set of individuals which has dictatorial power and its each member is a vetoer. It will be shown that an oligarchy is a set of vetoers if it exists. This research was partially supported by the Ministry of Education, Science, Sports and Culture, Grant-in-Aid for Scientific Research (C), 20530165, and the Grant-in-Aid from the Zengin Foundation for Studies on Economics and Finance in Japan.     

Product cycles, endogenous skill acquisition, and wage inequality

Abstract .  This paper presents an endogenous product cycle overlapping generations model, where the supply of skilled labour is endogenously determined. This is used to examine how production shifts through imitation by developing countries affect the domestic wage differential and supply of skilled labour in developed countries. In the model, production shifts increase the demand for researchers in developed countries and cause higher relative wages for skilled labour: this leads to more individuals acquiring the skills. As a consequence, the model helps to explain the simultaneous increase in the domestic wage gap and in the supply of skilled labour observed in developed countries.     

Empirical Analysis of Brands: A Survey

In this paper, we survey the empirical analysis of brands. The difficulty in this area of research is that even though a brand is easily identifiable, its economic roles are not directly observable. We first discuss methods where the effect of a brand is measured as the unobservable component of sales or price of a product, which researchers recover as a residual of the sales or price regression. We then describe the approaches to estimate the various roles of brands, such as providing information and increasing the utility of consumption. Finally, we provide examples of research that highlight the role of brands in exploiting the irrationality of consumers for profit.     

The cost-effectiveness of dulaglutide versus insulin glargine for the treatment of type 2 diabetes mellitus in Japan

Aims: Dulaglutide is a new once weekly glucagon-like peptide-1 (GLP-1) receptor agonist administered via a disposable auto-injection pen for the management of type 2 diabetes mellitus (T2DM). The objective of this study was to estimate the cost-effectiveness of dulaglutide vs insulin glargine for the management of T2DM from a Japanese healthcare perspective, in accordance with recently approved Japanese Cost-Effectiveness Guidelines.

Methods: The IQVIA CORE Diabetes Model (version 9) was used to estimate the long-term costs and effects of treatment with dulaglutide and insulin glargine. Direct comparative data from the Araki 2015 trial (NCT01584232) was used to inform the analysis. Costs associated with treatment and complications were derived from Japanese sources wherever possible and inflated to 2015 Japanese Yen (JPY). Utilities were based upon a European systematic review of diabetes utilities and adjusted for use in a Japanese population. One-way and probabilistic sensitivity analyses (OWSA and PSA) were conducted on all inputs and key modeling assumptions.

Results: Dulaglutide 0.75?mg was associated with higher quality-adjusted life years (QALYs), life years (LYs), and total costs, compared to insulin glargine, resulting in an incremental cost-effectiveness ratio (ICER) of 416,280 JPY/QALY gained. Treatment with dulaglutide increased the time alive and free from diabetes-related complications by 4 months. OWSA and PSA indicated that results were robust to plausible variations in input parameters and modeling assumptions.

Limitations: Key limitations of this study are similar to other cost-utility analyses of diabetes, including the extrapolation of short-term clinical trial data into lifelong durations. In addition, due to the lack of robust published Japanese data, some values were derived from non-Japanese sources.

Conclusions: This analysis suggests that dulaglutide 0.75?mg may be a cost-effective treatment alternative to insulin glargine for patients with T2DM in Japan.     

Long run equilibria in an asymmetric oligopoly

Summary. Consider an oligopolistic industry composed of two groups (or populations) of firms, the low cost firms and the high cost firms. The firms produce a homogeneous good. I study the finite population evolutionarily stable strategy defined by Schaffer (1988), and the long run equilibrium in the stochastic evolutionary dynamics based on imitation and experimentation of strategies by firms in each group. I will show the following results. 1) The finite population evolutionarily stable strategy (ESS) output is equal to the competitive (or Walrasian) output in each group of the firms. 2) Under the assumption that the marginal cost is increasing, the ESS state is the long run equilibrium in the stochastic evolutionary dynamics in the limit as the output grid step, which will be defined in the paper, approaches to zero. Received: September 19, 1997; revised: June 18, 1998