Price cointegration in spatial markets: An application to milkfish markets in Taiwan

Abstract

The objectives of this study are to analyze the interdependent behavior of lead‐lag milkfish price adjustments between vertically‐related markets (from production to consumption) as well as between five major horizontally‐related wholesale markets. Empirical results show that there is a two‐way lead‐lag cointegrating price relationship between milkfish wholesale and retail markets. Since the fish wholesale market cannot completely and quickly assimilate the retail market information, the speed of response of wholesale prices to retail price changes is relatively slow, inducing low pricing efficiency. The Taipei wholesale market appears to cause the greatest leadership impact on the milkfish price formation compared to other wholesale markets in both the long‐run and short‐run. The results also reveal that there is a high degree of integration relationship between the horizontally integrated wholesale markets (Chiayi, Changhwa and Taichung) for milkfish in the southwestern region within a short distance.     

“Indirect selection” for genetic change: A quantitative analysis illustrated with Macrobrachium rosenbergii

“Indirect selection” is exerted on a trait indirectly, by means other than artificial selection for the trait itself. Expressions are derived for calculating the intensity of indirect selection in aquaculture environments. The calculations are illustrated with growth-rate data on M. rosenbergii from farm ponds in Thailand, and with computer-generated data which simulate measurements made during a multiple mark-recapture experiment. Indirect selection for growth is probably negligible in Thai prawn farms and hatcheries at present, but small changes in management practice could exert strong indirect selection on growth rate. One very effective change appears to be collecting broodstock as early in the production cycle as possible. Control of indirect selection may be useful for the genetic improvement of aquaculture stock, especially in developing countries and other situations where an intensive artificial selection program is not economically or biologically desirable. Like all selection programs, the probability of success is critically dependent on the genetics of the traits being selected.     

Distribution and habitat characteristics of three sympatric cetacean species in the coastal waters of Matang,Perak, Peninsular Malaysia

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Einfluss selektiver mechanischer Fruchtbehangsregulierung auf Ethylensynthese als Stressindikator sowie Ertrag und Fruchtqualität bei Kernobst

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