Estimation of population origin–interchange–destination flows on multimodal transit networks

Combining ITS and optimization in public transportation planning: state of the art and future research paths

“…In detail, as a seed OD matrix is required for IPF implementation, Ji et al [42,43] derived such a matrix within hybrid IPF-based methodologies, using APC data. The simultaneous presence of AFC and AVL/farebox data has also been exploited within rigorous estimation algorithms to overcome the difficulty of distinguishing short activities from transfers when trying to identify linked trips [43][44][45][46][47].…”

“…Lack of integration among various data sources: Cumbersome procedures are required, so that the inputs required by a planning/design model, specific practitioners' knowledge and the outputs of monitoring systems may be consolidated in a common framework. Different degrees of fleet penetration: While AVL systems are typically installed on entire bus fleets, the same is not true for APCs which may be deployed on 10-15% of the fleet [8,46]. The availability of passenger demand data or lack thereof dictates the analysis that can be undertaken, as without APC/AFC the latter is inevitably limited to operational characteristics such as speed, delay and reliability.…”

“…Inevitably, benefits in modeling accuracy obtained by exploiting ITS data naturally depend on the quality of the data utilized [46,105]. The latter is dictated by the technical specifications of the ITS system deployed [72] as well as the archiving process [8].…”

“…The use of ITS data may undeniably provide answers on a broad spectrum of transportation research questions, from long-term planning to real-time control strategies. Nevertheless, AFC and APC data have limitations for some analyses, as critical elements required for decoding traveler choices are lacking [19,46,105]. In this context, demand-related issues such as mode shift behavior and induced demand cannot be exclusively accounted for, by solely using ITS data [17].…”

“…This process requires the definition of arbitrary thresholds for spatial and temporal proximity, reasonably resulting to the inability of linking a significant portion of individual trips [39]. In this case, the validation of inference methodologies is contingent on the availability of actual passenger counts [46,53]. When survey data is lacking, the inclusion of historical OD flow or onboard survey data [42] and the comparison of different estimation methodologies are alternative options to assess consistency of results [46].…”