Forschungsschwerpunkt Marktprozeß und Unter- nehmensentwicklung Research Area Market Processes and Corporate Development

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discussion papers

FS IV 00 – 22

Network Competition in Nonlinear Pricing Wouter Dessein

Université Libre de Bruxelles

December 2000

ISSN Nr. 0722 - 6748

Forschungsschwerpunkt Marktprozeß und Unter-

nehmensentwicklung

Research Area

Market Processes and

Corporate Development

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Zitierweise/Citation:

Wouter Dessein, Network Competition in Nonlinear Pricing, Discussion Paper FS IV 00-22,

Wissenschaftszentrum Berlin, 2000.

Wissenschaftszentrum Berlin für Sozialforschung gGmbH, Reichpietschufer 50, 10785 Berlin, Tel. (030) 2 54 91 – 0 Internet: www.wz-berlin.de

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ABSTRACT

Network Competition in Nonlinear Pricing by Wouter Dessein

Previous research has argued that, in the mature phase of competition, telecommunications networks may use access charges as an instrument of collusion. We show that this result depends totally on the assumption of linear pricing. Though under nonlinear pricing, the access charge alters the way networks use menus of tariffs to discriminate implicitly among heterogeneous customers, profits are then independent of the access charge, or, if participation constraints are binding, are maximized by the welfare maximizing access charge. In the entry phase, networks often differ in cost structure. An access markup then affects the level playing field between networks. .

Keywords: Telecommunications, Interconnection, Two-way Access, Competition Policy, Nonlinear Pricing

ZUSAMMENFASSUNG

Netzwettbewerb bei nichtlinearer Preispolitik

Die industrieökonomische Forschung hat bisher gezeigt, daß in der Marktphase der Reife, beim Wettbewerb von Telekommunikationsnetzen die Zugangsgebühren als ein Instrument des kollusiven Verhaltens eingesetzt werden können. Es wird gezeigt, daß dieses Ergebnis vollständig von den Annahmen des linearen Preisverhaltens abhängt.

Obwohl bei nichtlinearer Preispolitik Zugangsgebühren den Einsatz von Tarifmenüs der Netzwerkbetreiber hinsichtlich einer impliziten Diskriminierung zwischen heterogenen Nachfragern beeinflussen, sind die Gewinne dann aber unabhängig von den Zugangsgebühren oder, wenn Teilnahmebeschränkungen bindend sind, dann werden sie maximiert durch die wohlfahrtmaximierenden Zugangsgebühren. In der Markteintrittsphase sind Netze oft durch Unterschiede in der Kostenstruktur gekennzeichnet. Ein Zugangsgebührenzuschlag beeinflußt dann das Niveau, auf dem der Wettbewerb der Netzanbieter stattfindet.

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