T HIS article is based on a milk supply adjustment study. A primary objective was to test the use of linear programming techniques on the problems of farmers: how useful it would be for telling farmers what production adjustments would pay in response to changes in technical and economic conditions. The empirical results illustrate particular extensions in the application of programming techniques, but, more important, the results are of interest from two viewpoints: first, they indicate profitable lines of change in production when facing a range of changes in conditions of factor supply, prices of labor, prices of milk, and technical possibilities. Second, they offer reasonable explanations of changes taking place in important sectors in the southern states. The data were drawn largely from dairy farms in the Piedmont areas of North Carolina, but the empirical results should also apply in general to the much larger Piedmont region of the South and, to a somewhat lesser extent, to the larger areas in which cotton and tobacco are major crops. Production of milk for fluid use increased rapidly on these farms in the North Carolina Piedmont areas between I949 and I954. Expansion of dairying was accompanied by certain changes: enlargement of smaller farms by the renting of additional land, an increase in production of pasture and hay, shifts from lower-producing breeds to the Holstein breed, elimination of cotton or tobacco on many of the dairy farms, reduction in labor supply, and an increase in use of tractors. Assumptions

THE basic question to which this paper is addressed is "What is the importance of distance in determining the pattern of Western European trade?"The importance of distance in the pattern of trade has, of course, always been recognized.The assumption of "no transport costs," which has always been necessary in expositions of theories of international trade, is a recognition of the fact that transport costs, that is, the costs of covering distance, exist and are significant; so that abstraction from them has to be made quite explicitly in order to analyze other elements such as factor endowments.' 0 0 t 0 0 0 "inCq 0 e oo HO ~, "d0 80 8 00 0 * .. 99"o 'A-.

Minimum-variance hedging of a contingent claim in discrete time is suboptimal when the contingent claim is hedged for multiple periods and the objective is to maximize the expected utility of cumulative hedging errors. This is because the hedging errors are not independent. The difference between a minimum-variance hedge and the optimal multiperiod hedge is called the hedging demand and depends on the hedger's preferences, the characteristics of the contingent claim, the trading frequency and horizon, and most importantly the joint distribution of the contingent claim and the underlying security prices. Since modeling this joint distribution is empirically controversial, I examine nonparametrically the economic importance of hedging demands in the case of hedging Standard & Poor's 500 index options.

The nature and characteristics of economic fluctuations in Eastern European Centrally Planned Economies are analyzed. When cycles are identified by the deviation from a fitted deterministic trend, they are seen to coincide temporally. This common variation is found for Net Material Product (NMP) and Investment. The implications of the common variation of CPE cycles are discussed. Possible explanations of this phenomenon are discussed with emphasis on a possible link via trade. We then examine the possibility that the time series contain unit roots. We are unable to reject this hypothesis for the variables in question. This suggests using procedures for detrending nonstationary time series suggested by Beveridge and Nelson. Such an analysis is performed and the implications are discussed. We find that there remains some common variation in the cyclical component of output, but to a lesser extent. The implications of these findings for future research on CPE cycles are discussed.

A presidential vote function and a presidential approval ratings function are jointly estimated for U.S. post-war observations. The estimation technique treats the two equations as seemingly unrelated regressions with unequal numbers of observations. Cross-equation restrictions implying that voters and poll respondents use identical standards in judging the economic performance of incumbents are imposed and tested. Estimates show that both votes and approval ratings are influenced by GNP growth and inflation. The results suggest that poll respondents are more inflation averse than voters; however, tests of this hypothesis are not conclusive.