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Asserting that “elementary teachers are going to become increasingly involved with economic concepts, and that economic education at the elementary level is at an important developmental state,” Professor Ramsett explains how economics can be included in the elementary school curriculum without taking other subject matter out, and suggests approaches to the training of elementary teachers. He describes some innovative techniques being used at North Dakota's New School of Behavioral Studies, illustrates methods for motivating pupils, shows how economic concepts can be related to other subjects (such as arithmetic), and calls for cooperation between educators and liberal arts faculties in preparing the elementary teacher. 相似文献
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This paper presents a framework for estimating an indirect production function and then applies it to aggregate US agriculture. Issues addressed include tests of standard hypotheses about the underlying technology (homotheticity, neutral technical change, etc.) as well as examination of consistency in aggregation and the effects of changes in the level of aggregate expenditure on farm output. Since there already exist several studies empirically describing agricultural production technologies with indirect objective functions, one might fairly ask whether this paper really breaks any new ground? We feel that it does. One reason is that existing studies (e.g. Binswanger, 1974; Lopez, 1980; Ball and Chambers, 1982; Ray, 1982; and Weaver, 1983) all rely on either profit or cost functions. To date there appears to be only one study using an indirect production (Appelbaum, 1979), and it is not in agriculture. This seems unfortunate because there are many instances in agriculture for which an indirect production function (or revenue function approach) seems more appropriate. The reason why relates directly to one's belief about the objective function and constraints farmers face. Ultimately, it seems plausible in a certainty framework that producers maximize profits. And since cost minimization and output maximization are just constrained versions of profit maximization, both cost and indirect production functions are more appropriately viewed as restricted profit functions. What differs is the constraint. Assuming cost minimization implies that farmers are constrained by a fixed output which they must produce; in most instances, this is implausible. More likely, the level of output is itself a choice variable. Output maximization, on the other hand, suggests that the main constraint is the amount of money that producers can muster to hire resources. In other words, farmers may face binding constraints in obtaining the profit maximizing level on expenditure on input utilization. One might think that expenditure may not be a binding constraint because there exists a relatively active US credit market. However, the US credit market is far from being perfectly competitive in a stylized sense, and thus, the possibility of a farmer being able to finance a given level of expenditure may be limited. Readers familiar with the dual approach to production problems may already be asking why these ideas rule out cost functions since it is well known that the cost function is the distance function of the indirect production function (Blackorby et al., 1978)? In principle, therefore, one could always estimate a cost function and then invert it to obtain the indirect production function. There are two problems with this approach: the first is that if output maximization is truly the objective, output is not predetermined and cannot be treated as exogenous in cost function estimation. Second, estimation of direct and indirect functions using the same data set does not always yield comparable results. Estimation of a transcendental logarithmic (translog) indirect production function and a translog cost function, separately, does not generally yield identical estimates of the Allen elasticities of substitutions. Solving the first problem in simple, but the second suggests that estimation should proceed on the basis of the objective function the researcher deems most appropriate. Therefore, if output maximization is more plausible than cost minimization an indirect production function should be used. The plan of the paper is as follows. We first outline the theoretical developments necessary to our approach (included are conditions necessary for consistent aggregation over firms). We then present estimates of an indirect production function and use these estimates to investigate the plausibility of various restrictions on the technology, consistency in aggregation, substitution possibilities in agricultural production, and the effect of expenditure on agricultural input utilization. The paper closes with a discussion of the results and suggestions for future research. 相似文献
980.
The existence of persistent technical inefficiency offers the opportunity for a ‘free lunch’ not typically implied by the neoclassical theory of the firm. When external effects are related to the use of particular inputs, reduction of persistent technically inefficient levels of input use represents a means of reducing external impacts. An important example is found in agriculture where substantial environmental impacts are generated by particular inputs. Within this context, this paper considers the usefulness of data envelopment analysis (DEA) for estimation of potential input reductions and assessment of potential reductions of environmental impacts of agricultural inputs. An application for French cereal production provides estimates that indicate that substantial potential exists for reduction of input use and environmental impacts. 相似文献