Explaining material traces of movement as proxies for past movement is fundamental for understanding the processes behind why people in the past traversed the landscape in the way that they did. For this, least-cost path analysis and the use of slope-based cost functions for estimating the cost of movement when walking have become commonplace. Despite their prevalence, current approaches misrepresent what these cost functions are, their relationship to the hypotheses that they aim to represent, and their role in explanation. As a result, least-cost paths calculated using single cost functions are liable to spurious results with limited power for explaining known past routes, and by extension the decision-making processes of past people. Using the ideas of multiple model idealisation and robustness analysis, and applied via a tactical simulation, this study demonstrates that similar least-cost paths can be produced from slope-based cost functions representing both the same hypothesis and different hypotheses, suggesting that least-cost path results are robust but underdetermined under the tested environmental settings. The results from this tactical simulation are applied for the explanation of a Roman road in Sardinia. Using probabilistic least-cost paths as an approach for incorporating multiple cost functions representing the same hypothesis and error in the digital elevation model, it is shown that both model outcomes representing the minimisation of time and energy are unable to explain the placement of the Roman road. Rather, it is suggested that the Roman road was influenced by pre-existing routes and settlements.

将运动的物质痕迹解释为过去运动的代表，对于理解过去人们以这种方式穿越景观背后的过程至关重要。为此，最小成本路径分析和使用基于坡度的成本函数来估计步行时的运动成本已变得司空见惯。尽管它们很普遍，但当前的方法歪曲了这些成本函数的含义、它们与它们旨在表示的假设的关系以及它们在解释中的作用。因此，使用单一成本函数计算的最低成本路径很容易产生虚假结果，其解释已知过去路线的能力有限，并延伸到过去人们的决策过程。利用多模型理想化和鲁棒性分析的思想，并通过战术模拟进行应用，本研究表明，可以从代表相同假设和不同假设的基于斜率的成本函数产生类似的最低成本路径，这表明最低成本路径路径结果是稳健的，但在测试的环境设置下不确定。该战术模拟的结果用于解释撒丁岛的罗马道路。使用概率最小成本路径作为在数字高程模型中合并代表相同假设和误差的多个成本函数的方法，结果表明代表时间和能量最小化的两种模型结果都无法解释罗马道路的位置。相反，有人认为罗马道路受到了先前存在的路线和定居点的影响。