Choice

A choice is the range of different things from which a being can choose. The arrival at a choice may incorporate motivators and models. For example, a traveler might choose a route for a journey based on the preference of arriving at a given destination at a specified time. The preferred (and therefore chosen) route can then account for information such as the length of each of the possible routes, the amount of fuel in the vehicle, traffic conditions, etc. Simple choices might include what to eat for dinner or what to wear on a Saturday morning – choices that have relatively low-impact on the chooser's life overall. More complex choices might involve (for example) what candidate to vote for in an election, what profession to pursue, a life partner, etc. – choices based on multiple influences and having larger ramifications. Freedom of choice is generally cherished, whereas a severely limited or artificially restricted choice can lead to discomfort with choosing, and possibly an

Exploiting pedestrian WiFi traces for destination choice modeling

Loïc Tinguely

My master thesis proposes a general methodology to model pedestrian destination choice from WiFi localization in multimodal transport facilities (e.g., airports, railway stations). It is based on the output of [Danalet, A., B. Farooq and M. Bierlaire (2014) A Bayesian approach to detect pedestrian destination-sequences from WiFi signatures, Transportation Research Part C: Emerging Technologies, 44, 146–170.] method to generate candidates of activity-episode sequences from WiFi measurements, locations of activities on a map and prior information. Destination choice is nested to the activity choice. An individual first chooses an activity ([Danalet, A. and M. Bierlaire (2015) Importance sampling for activity path choice, paper presented at the 15th Swiss Transport Research Conference (STRC), Monte Verità, Ascona, Switzerland.]), and then selects the destination where to perform it. We propose an approach to model destination choice accounting for panel nature of data. We compare static, dynamic strict exogenous and dynamic model with two different agent effect corrections inspired by [Wooldridge, J. M. (2002) Simple solutions to the initial conditions problem in dynamic, nonlinear panel data models with unobserved heterogeneity, Journal of applied econometrics, 44, ISSN 1753-9196.] method. In a case study using WiFi traces on EPFL campus, we focus on one activity type: catering. The choice set contains 21 alternatives on campus (restaurants, self-services, cafeterias, ...). Our models reveal that the choice of a catering facility depends mostly on habits (e.g., where an individual ate the previous time), distance to walk from the previous activity-episode (calculated with a weighted shortest path algorithm) but less on destination specific determinants (e.g., price, capacity). The models are successfully validated using the same WiFi dataset and we forecast possible changes concerning catering destinations on the campus.

2015

Device-to-Device Assisted Video Transmission

Laura Toni, Wenwen Zhou

To increase spectrum efficiency, researchers envi- sion a device-to-device (D2D) communication system in which a closely located mobile device pair may share the same spectrum with a cellular user. By opportunistically choosing the frequency, the D2D pair may increase the spectrum efficiency in terms of data rate per Hertz, at the price of additional interference to that cellular user. In previous models, users either stop cellular transmission and switch to D2D transmission or vice versa. However, if the cell is fully loaded, a D2D pair will not be able to switch back to the conventional mode because no extra resource is available. In this paper, we propose a D2D assisted model, where a D2D link is enabled to assist transmission, while keeping the conventional cellular transmission. In this way, the D2D link can be turned on and off according to the link quality. We also propose a PHY-layer study for the transmission scheme in such a way that the system throughput and the video reception quality is always improved compared to a conventional link.

2013

Exploiting pedestrian WiFi traces for destination choice modeling

Loïc Tinguely

2015

The Window : A guided Choice between Physics and Ecology

Exploiting pedestrian WiFi traces for destination choice modeling

Device-to-Device Assisted Video Transmission

The Window : A guided Choice between Physics and Ecology

Exploiting pedestrian WiFi traces for destination choice modeling

Device-to-Device Assisted Video Transmission