We analyze the differences between corner solution and survival models in estimating the marginal cost of track renewals. Both approaches describe the renewal process in intuitively similar ways but have several methodological distinctions. Using Swedish data for the 1999–2016 period, results suggest the median marginal costs per gross ton-km from corner solution and survival models are SEK 0.0066 and SEK 0.0031, respectively. Since several European countries use information about marginal costs as a basis for track user charges, the choice of estimation method is obviously important. Our conclusion is that the corner solution model is more appropriate in this case, as this method considers the impact traffic has both on the probability of renewal and on the size of the renewal cost. The survival approach does not consider the latter as part of the estimations, which is problematic when we have systematic cost variations due to traffic and infrastructure characteristics.

我们分析了转弯解法和生存模型之间的差异，以估算轨道更新的边际成本。两种方法都以直观上相似的方式描述了更新过程，但是在方法上存在一些区别。使用瑞典1999-2016年的数据，结果表明，转弯解和生存模型得出的每毛吨公里的边际成本中位数分别为0.0066瑞典克朗和0.0031瑞典克朗。由于几个欧洲国家使用边际成本信息作为跟踪用户费用的基础，因此估算方法的选择显然很重要。我们的结论是，在这种情况下，转弯解模型更合适，因为该方法考虑了流量对续订概率和续订成本大小的影响。