傳統電信產業中，電信事業多被視為自然獨占產業並由政府經營。但隨著資訊通信技術的進步，電信自由化成為必然的趨勢。當廠商的數目愈來愈多時，便產生了接續費的訂價問題。然而，目前大多數的文獻中，追隨廠商的零售價格都是視為給定的，因此，本文主要在研究追隨廠商非價格接受者時，廠商之間的接續費該如何訂定，而此接續費的訂價和廠商為價格接受者時又有何不同。
本文以 Armstrong, Doyle and Vickers (1996) 的一般模型為主，分為簡單模型與加入固定成本的模型，其中再以追隨廠商非價格接受者與價格接受者時，分別去探討社會福利最大化的最適接續費並且比較之。
結果發現，在簡單模型下：(1) 當追隨廠商非價格接受者時，最適接續費等於 ECPR 加上領導廠商為了壓倒追隨廠商市場力之補貼；(2) 追隨廠商為價格接受者時，最適接續費等於邊際訂價。而在加入固定成本的模型中：(1) 追隨廠商非價格接受者時，最適接續費等於 ECPR 加上領導廠商為了壓倒追隨廠商市場力之補貼；(2) 追隨廠商為價格接受者時，最適接續費會等於 ECPR 加上一正的 Ramsey 項，此結果和 Armstrong, Doyle and Vickers (1996) 的一般模型類似，即最適接續費會大於 ECPR。
另外，在簡單模型中的比較發現，領導廠商的零售價格，在追隨廠商非價格接受者時大於其為價格接受者時，也就是愈競爭時，管制者傾向將領導廠商的零售價格訂定較小；但是接續費的大小則不一定，要視領導廠商的機會成本大小以及補貼的大小而定。而在固定成本模型中的比較發現，若領導廠商的零售價格，在追隨廠商非價格接受者時小於其為價格接受者時，則接續費在追隨廠商非價格接受者時也會小於其為價格接受者時。

The telecommunication industry is most likely to be a natural monopoly industry and is usually regulated by government. With the technology progress in communication industry, the regulation may not be social desirable. As the number of firms in a telecommunication industry increases, the interconnection among firms are desirable and access pricing issue arises. In most of the previous research in telecommunication industry, the retail price of the followers is assumed to be fixed. The purpose of this paper is to discuss the access pricing policy when the retail price of followers is not given. In addition, we compare the access prices in cases of given retail price and variable retail price. Based on Armstrong, Doyle and Vickers’ (1996) model, we discuss the incumbent’s optimal access prices when there are many price taking followers and also when there is only one follower.
We have found in our model that: (1) when the follower is not a price taker, the optimal access charge is ECPR plus the subsidy on access paid to the follower in order to maintain its market power. (2) when the followers are price takers, the optimal access charge is marginal cost pricing. When we consider the existence of the fixed cost of an incumbent in the simple model, we have found that: (1) when the follower is not a price taker, we have the same as in the simple model without fixed cost. (2) when the followers are price takers, the optimal access charge is ECPR plus a positive Ramsey term, i.e., optimal access charge is greater than the ECPR.. This result is similar to the result in Armstrong, Doyle and Vickers (1996). In addition, comparing with the price taking followers case, we have found that the leader’s retail price is higher when the follower is not a price taker. However, the comparing of the access charges between two cases is not possible. It depends both on the leader’s opportunity costs subsidy to the followers. With the fixed cost, the leader’s retail price is higher when the followers are price takers, the optimal access charge is also higher when the follower are price takers.

1.李秋薇，「電信自由化發展比較與借鏡」，《通訊雜誌》第57期，1998年10月。
2.彼得潘，「我國電信自由化現況與展望」，《通訊雜誌》第68期，1999年9月。
3.廖賢洲，「通信費營收歸屬原則調整之探討」，《通訊雜誌》第95期，2001年12月。
4.盧群育 (2000)「電信網路市場接續費定價之研究」， 國立中央大學產業經濟研究所碩士論文。
5.Armstrong, M., C. Doyle and J. Vickers, “The Access Pricing Problem: A Synthesis”, The Journal of Industrial Economics, June 1996, vol.44, pp 131-50.
6.Armstrong, M., “Network Interconnection in Telecommunication”, The Economic Journal, May 1998, vol.108, pp 545-64.
7.Baumol, William J. and J. Gregory, Sidak, “Toward Competition in Local Telephony”, Cambridge, Mass MIT Press Washington, D.C American Enterprise Institute for Public Policy Research, 1994.
8.Yannelis Demetrius, “On Access Pricing with Network Externalities”, Atlantic Economic Journal, June 2002, vol.30, No.2, pp 186-90.
9.Ergas Henry, “Acess and Interconnection in Network Industries”, http://www.necg.
Com.au/pappub/papers-ergas-access.pdf, 1998.
10.Katz, Michael L. and C. Shapiro, “Network Externalities, Competition, and Compatibility”, American Economic Review, 1985, vol.75, No3, pp 424-40.
11.Laffont Jean-Jacques and Jean Tirole, “Access Pricing and Competition”, European Economic Review, 1994, vol.38, pp 1673-710.
12.Laffont Jean-Jacques, Patrick Rey and Jean Tirole, “Network Competition：I. Overview and nondiscriminatory pricing”, Rand Journal of Economics, 1998, vol.29, NO.1, pp 1-37.