Technology adoption,impact, and extension in developing countries’ agriculture: A review of the recent literature

Given the stagnant agricultural productivity and persistent food insecurity in low-income countries—notably in sub-Saharan Africa (SSA)—there has been continued interest in the adoption of new technology and its impact on productivity in these regions. To increase crop yields and sustain yield gains, recent case studies of technology adoption unanimously recommend the adoption of integrated farm management systems, particularly in SSA. On the other hand, there have been increasing numbers of studies on social network or farmer-to-farmer technology extension. These studies explore more efficient extension systems than traditional public-sector extension approaches. This article reviews both recent case studies of technology adoption and its productivity impacts as well as studies on agricultural extension to identify common findings, shortcomings, and major remaining issues.     

Perfect foresight dynamics in binary supermodular games

The present paper considers equilibrium selection in binary supermodular games based on perfect foresight dynamics. We provide complete characterizations of absorbing and globally accessible equilibria and apply them to two subclasses of games. First, for unanimity games, it is shown that our selection criterion is not in agreement with that in terms of Nash products, and an example is presented in which two strict Nash equilibria are simultaneously globally accessible when the friction is sufficiently small. Second, a class of games with invariant diagonal are proposed and shown to generically admit an absorbing and globally accessible equilibrium for small frictions.     

Encoding of high-frequency order information and prediction of short-term stock price by deep learning

Predicting the price trends of stocks based on deep learning and high-frequency data has been studied intensively in recent years. Especially, the limit order book which describes supply-demand balance of a market is used as the feature of a neural network; however these methods do not utilize the properties of market orders. On the other hand, the order-encoding method of our prior work can take advantage of these properties. In this paper, we apply some types of convolutional neural network architectures to order-based features to predict the direction of mid-price trends. The results show that smoothing filters which we propose to employ rather than embedding features of orders improve accuracy. Furthermore, inspection of the embedding layer and investment simulation are conducted to demonstrate the practicality and effectiveness of our model.     

Corporate restructuring in Japan: Who monitors the monitor?

Peek and Rosengren [Peek, J., Rosengren, E., 2005. Unnatural selection: Perverse incentives and the misallocation of credit in Japan. American Economic Review 95, 1144–1166] showed that, when the bubble economy era ended, regulatory forbearance and perverse incentives allowed Japanese banks to engage extensively in evergreening. This is the first comprehensive study to empirically analyze the economics of private debt restructurings of financially distressed companies in Japan, where the corporate monitoring mechanism is not market based but large-stakeholder based – typically, banks and affiliated companies. These stakeholders are expected to efficiently resolve potential bankruptcy or collapse with better information resulting from long-term relationships with the distressed firms. Our study, however, finds that private restructurings led by them failed because of delays in implementing fundamental solutions. Forbearance in addressing the needs of distressed firms demonstrates the weakness of such stakeholders in instituting discipline, hence the need for a system to “monitor the monitor”.     

Economic geography and endogenous determination of transport technology

This paper studies the interdependence of economic geography and transport technology. A two-region model is used to obtain the conditions for the modern transport technology to be adopted in an economy. In particular, the impact of economic geography upon the adoption of the modern technology is examined. Furthermore, I discuss what combination of economic geography (symmetric or core–periphery pattern) and transport technology (traditional or modern technology) is to be realized in an economy.     

Pricing average options on commodities

This study proposes a new approximation formula for pricing average options on commodities under a stochastic volatility environment. In particular, it derives an option pricing formula under Heston and an extended λ‐SABR stochastic volatility models (which includes an extended SABR model as a special case). Moreover, numerical examples support the accuracy of the proposed average option pricing formula. © 2010 Wiley Periodicals, Inc. Jrl Fut Mark Mark 31:407–439, 2011     

Efficient static replication of European options under exponential Lévy models

This study proposes a new scheme for the static replication of European options and their portfolios. First, a general approximation formula for efficient static replication as an extension of Carr P. and Chou A. (1997, 2002) and Carr P. and Wu L. (2002) is derived. Second, a concrete procedure for implementing the scheme by applying it to plain vanilla options under exponential Lévy models is presented. Finally, numerical examples in a model developed by Carr, P., Geman, H., Madan, D., and Yor M. (2002) are used to demonstrate that the replication scheme is more efficient and more effective in practice than a standard static replication method. © 2008 Wiley Periodicals, Inc. Jrl Fut Mark 29:1–15, 2009     

A Pacific free trade area

Great Britain's desire to join the Common Market has given a fresh impetus to the plans of a Pacific-Asiatic free trade area. Members of PAFTA are to be Japan, the United States, Canada, Australia, and New Zealand. By means of an economic integration of these nations, particularly Japan is interested in stabilising its position in the world economy and not to stand completely outside regional unions. Already last year, INTERECONOMICS published a critical comment to the PAFTA plans written by the Australian professor, H. W. Arndt. In view of the manifold problems and the economic disadvantages to be anticipated, he declared against an Australian participation in this project. In the following article, Professor Kojima, the initiator of the Pacific integration plans, takes a different point of view.     

Budget constraint of a firm and economic theory

Summary Firms in reality are subject to budget constraints which general equilibrium theorists have paid little attention. Using Morishima (1950, 1992) model, this paper deals with firms that are subject to budgets pertaining to sales and investment decisions, and proves the existence of a general equilibrium. We show that an economy with firms subject to budgets does not necessarily satisfy the efficiency proposition, and clarify how the total profit maximum condition in the Arrow-Debreu (1954) type economy ensures an efficiency in a limited dynamic sense.The author is grateful to Professors J. Iritani, H. Nagatani, and K. Urai who gave useful comments on occasions of Saturday Workshop on Economic Theory and Mathematics. He is also grateful to Professor M. Kaneko for his useful comments on an earlier version of the paper Kuga (1993), to which this article is closely related.