This paper studies access pricing under three regimes: regulated access (VSR), negotiated access with discriminatory pricing (VSD) and negotiated access with non-discriminatory pricing (VSN). We compare each regime along three metrics: network quality, consumer surplus, and social welfare. To do so, we use a three-stage game, in which the regulator can commit to the access tariff under VSR and the network firm and the transport operators need to bargain over the access tariff under VSD and VSN. Each approach is second best, resulting in equilibrium qualities and quantities that are less than first-best levels, and the comparison between regulated and negoitated access is ambiguous. However, under a wide range of circumstances VSD and VSN result in greater investment to upgrade network quality than VSR. Computational analysis reveals that if the bargaining power of the network firm under negotiated access is sufficiently strong, VSD tends to result in higher social welfare than VSR. However, VSR often results in higher consumer surplus.

中文翻译：

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垂直分隔的铁路系统中的调节价格与协商价格

本文研究了三种定价下的访问定价：管制访问（VSR），具有歧视性定价的协商访问（VSD）和具有非歧视性定价的协商访问（VSN）。我们根据三种指标比较每种制度：网络质量，消费者剩余和社会福利。为此，我们使用三阶段博弈，其中监管者可以承诺根据VSR和网络公司承担接入费，而运输运营商需要就VSD和VSN规定的接入费进行讨价还价。每种方法都是次优的，导致均衡的质量和数量少于最佳的水平，并且受监管的访问与协商访问之间的比较是模棱两可的。但是，在广泛的情况下，与VSR相比，VSD和VSN花费了更多的钱来升级网络质量。计算分析表明，如果网络公司在协商访问下的议价能力足够强，则VSD往往会比VSR带来更高的社会福利。但是，VSR通常会导致更高的消费者剩余。