This paper analyses and compares transferability of freight production (FP) and freight trip production (FTP) models to provide guidance on when, when not, and how to transfer models from one spatial context to another. Separate sets of model parameters are estimated for various industry sectors in two regions within Kerala, a Southern State of India and are transferred to Jaipur, a Northern State of India. Model performance in five different transfer combinations are assessed to understand the degree of transferability of FP and FTP models which included intrastate transfers within Kerala and interstate transfers to Jaipur. Two approaches of updating model parameters using locally collected data are evaluated – Bayesian updating and combined transfer estimation – with metrics that measure transferability improvement. The relative performance of transferred models revealed that the degree of transferability of freight models vary widely across industry sectors and depends on: (i) measure of business size and the (ii) metric of measuring freight activity. That is, employment-based models show better transferability than area-based models and FP models are more transferable than FTP models. The transferability results also suggested that the interstate transferability is higher than interstate transferability. Overall, the study findings will assist planning agencies to: (i) identify the locational characteristics that restrict the transferability of freight models, (ii) develop modelling strategies that focus on the appropriate metric of measuring freight and business size indicators, and (iii) reduce costs and resources in regions where there is lack of institutional capacity to develop freight demand model systems.

本文分析并比较了货运生产（FP）和货运行程生产（FTP）模型的可传递性，以提供有关何时何地不何时以及如何将模型从一个空间环境转移到另一个空间环境的指导。估计印度南部州喀拉拉邦两个地区各个行业的模型参数分别集，然后转移到印度北部州斋浦尔。评估了五种不同传输组合中的模型性能，以了解FP和FTP模型的可传输性程度，其中包括喀拉拉邦内的州内传输和斋浦尔的州际传输。评估了使用本地收集的数据更新模型参数的两种方法-贝叶斯更新和组合传输估计-以及用于度量可传输性改进的度量。转移模型的相对性能表明，货运模型的可转移性程度在各个行业之间差异很大，并且取决于：（i）业务规模的度量和（ii）度量货运活动的度量。也就是说，与基于区域的模型相比，基于就业的模型显示出更好的可传递性，而与FTP模型相比，FP模型具有更高的可传递性。转移性结果还表明，州际转移性高于州际转移性。总体而言，研究结果将有助于规划机构：（i）确定限制货运模型可转移性的位置特征；（ii）制定侧重于衡量货运和业务规模指标的适当度量的建模策略，