本文建構1995-1999年台灣公用氣體燃料事業廠商別的panel data。利用Translog成本函數模型,探討產業的規模、密度與範疇經濟,並且考量網路效果。此外,本文衡量廠商的最小有效規模,藉以推估合理的廠商家數。並且,進一步運用事前模擬合併,評估台灣北中南三區域天然氣廠商合併前後的效率。實證結果顯示,此產業具有規模、密度與範疇經濟的特性。根據最小有效規模產出與天然氣實際需求量,估測出天然氣廠商的最適家數,北部為3家,中部為1家,南部亦為1家。最後,我們比較合併前後的擴大型規模經濟係數,顯示合併後的區域廠商具擴大型規模經濟的效益。
This paper constructs a firm-level panel data set of the Taiwanese natural gas industry during 1995-1999. A translog cost function is used to investigate the effects of economies of scale, density and scope. The network effect is also taken into account. We measure the minimum efficient scale to estimate the optimal number of firms. Furthermore, we apply the simulated mergers to evaluate the efficiency pre- and post-merger of firms in the north, central and south regions of Taiwan. Empirical results show that, this industry possesses the characteristics of economies of scale, density and scope. According to the MES output and actual natural gas demand, we conclude the optimal number of firms in the north, central and south regions are 3, 1, and 1 respectively. Finally, we compare the coefficients of augmented scale of economies, pre- and post-mergers, and the results show that regional firms have the efficiency of economies of scale after merger.