Effect of Low pH on the Acid-Base Balance,Osmolality and Ion Concentrations of Giant Freshwater Prawn Macrobrachium Rosenbergii

Abstract

This study addresses the demand for fishery products in Taiwan.The generalizedmodels are selected with dynamic specification to analyze the demand structure for fisheryproducts,using quarterly data for the period 1979-1998.The empirical results show thatthe generalized inverse demand system with prices dependent on quantities is suitable forthe demand system of fish products in Taiwan.Also,the generalized inverse model fitsthe data better than do the other four nested models.The adjusting coefficient of dynamicbehavior is highly significant level within the models,implying that the fish consumption wasto be affected by both inertia and habit persistence.The own price flexibilities of all thefishery products are less than one which indicates that both the quantity of consumerdemand and the revenue of the fishermen are proceeding in parallel.The fishermen'srevenue can be increased only by the increase of the quantity demanded.本研究著重於台灣水產品消費需求量結構關係之實證估計，利用1979至1999年季別資料，建立一般化動態模型，推估需求彈性與分析。實證結果顯示台灣地區水產品需求體系模型選擇以一般化動態模型為最合適。動態行為的調整係數在模型中具有統計上的顯著性，表示漁產品的消費支出無法隨著當其消費數量與規模的變動迅速調整，會受到前期消費習慣及前期消費數量及規模影響，使短期的消費支出無法立即調整至最適。所以業者應依據這種需求行為的僵固性來促銷，配合重要傳統節日。所有漁產品自身數量彈性小於一，但消費數量增減對漁民收益的影響仍需依漁產品量價關係而定，水產品所推估自身數量彈性不具彈性，表示消費數量與漁民收益是同向變動，所以漁產品消費數量的增加，才能有助於漁民收益增加。