本研究利用1994及2000年主計處的家庭收支原始調查資料,分析不同所得群家計單位的一般消費及食品需求結構並作跨期比較,方法上應用Gaoetal.(1996)的兩階段LES-AIDS需求體系(two-stage LES-AIDS)衡量台灣家戶單位的消費預算配置,為了反應家庭品質差異,Cox and Wohlgenant(1986)的品質調整(quality adjusted)價格作為橫斷面資料估計需求函數的價格變數,家戶等值規模(household equivalent scale)變數將作為橫斷面家戶間偏好差異的替代變數。實證結果顯示:所得較低的家戶單位比高所得者須花費較高比例的消費支出於食物及醫療保健等維持基本生活條件的支出上;而高所得者則花費較大比例的消費支出在衣著、娛樂教育及交通運輸等屬服務性質的消費支出上。另外,低收入戶花費在主食費及副食品費的比例佔食品類的比例高達56.3%-62.8%,所得較高的家戶花費較高食品比例於在外伙食費上。再者,所得較高的中高收入戶的食品費的支出彈性比低及中低收入戶收入者具彈性。值得注意的是醫療保健的支出彈性,低收入戶從政府實施全民健保前的1994年,缺乏彈性的0.40上升至2000年全民健保實施五年後的1.06,中低及中高收入戶則分別從1.46及1.35下降至1.17及0.83,三種所得別有趨近的趨勢。最後,低所得的家庭其主食類的所得彈性明顯的高於非低所得家庭,外食對低所得群為奢侈品但對非低所得家庭為正常財。
The purpose of this study is to analyze the structure of household consumption and food demand in Taiwan households segmented by income. Nationwide Household Revenue and Expenditure Survey data of 1994 and 2000 is analyzed in this study and households will be ranged from lowincome, medium-low to medium-high income groups according to government poverty guideline using demand system to estimate the household consumption and food sub-demand system. Gao et al. (1996) two-stage budget allocation method will be employed to estimate the demand function (two-stage LES-AIDS). Cox and Wohlgenant (1986) quality-adjusted prices for each commodity are adopted to reflect variations in household quality. In addition, Household adult equivalent scale calculated by household characteristics serves as proxy variable of taste effect in cross-section demand model. Finally, demand elasticity for different income groups is calculated. The results show that food demands of low-income households are more responsive to income and prices than are those of medium-low and medium-high households in Taiwan.