ABSTRACT
This paper describes a data collection campaign and a dataset of BLE beacons for detecting and analysing human social interactions. The dataset has been collected by involving 15 volunteers that interacted in indoor environments for a total of 11 hours of activity. The dataset is released as a collection of CSV files with a timestamp, RSSI (Received Signal Strength Indicator) and a unique identifier of the emitting and of the receiving devices. Volunteers wear a wristband equipped with BLE tags emitting beacons at a fixed rate, and a mobile application able to collect and to store beacons. We organized 6 interaction sessions, designed to reproduce the three common stages of an interaction (Non Interaction, Approaching and Interaction). Moreover, we reproduced interactions by varying the volunteer's posture as well as the position of the receiving device. The dataset is released with a ground truth annotation reporting the exact time intervals during which volunteers actually interacted. The combination of such factors, provides a rich dataset useful to experiment algorithms for detecting interactions and for analyzing dynamics of interactions in a real-world setting. We present in detail the dataset and its evaluation in "Sensing Social Interactions through BLE Beacons and Commercial Mobile Devices", in which we focus on two orthogonal analysis: quality of the dataset and RSSI symmetry of the channel during the interaction stage between pairs of users.
ABSTRACT
Wearable sensing devices can provide high-resolution data useful to characterise and identify complex human behaviours. Sensing human social interactions through wearable devices represents one of the emerging field in mobile social sensing, considering their impact on different user categories and on different social contexts. However, it is important to limit the collection and use of sensitive information characterising individual users and their social interactions in order to maintain the user compliance. For this reason, we decided to focus mainly on physical proximity and, specifically, on the analysis of BLE wireless signals commonly used by commercial mobile devices. In this work, we present the SocializeME framework designed to collect proximity information and to detect social interactions through heterogeneous personal mobile devices. We also present the results of an experimental data collection campaign conducted with real users, highlighting technical limitations and performances in terms of quality of RSS, packet loss, and channel symmetry, and how they are influenced by different configurations of the user's body and the position of the personal device. Specifically, we obtained a dataset with more than 820.000 Bluetooth signals (BLE beacons) collected, with a total monitoring of over 11 h. The dataset collected reproduces 4 different configurations by mixing two user posture's layouts (standing and sitting) and different positions of the receiver device (in hand, in the front pocket and in the back pocket). The large number of experiments in those different configurations, well cover the common way of holding a mobile device, and the layout of a dyad involved in a social interaction. We also present the results obtained by SME-D algorithm, designed to automatically detect social interactions based on the collected wireless signals, which obtained an overall accuracy of 81.56% and F-score 84.7%. The collected and labelled dataset is also released to the mobile social sensing community in order to evaluate and compare new algorithms.
ABSTRACT
Indoor localization has become a mature research area, but further scientific developments are limited due to the lack of open datasets and corresponding frameworks suitable to compare and evaluate specialized localization solutions. Although several competitions provide datasets and environments for comparing different solutions, they hardly consider novel technologies such as Bluetooth Low Energy (BLE), which is gaining more and more importance in indoor localization due to its wide availability in personal and environmental devices and to its low costs and flexibility. This paper contributes to cover this gap by: (i) presenting a new indoor BLE dataset; (ii) reviewing several, meaningful use cases in different application scenarios; and (iii) discussing alternative uses of the dataset in the evaluation of different positioning and navigation applications, namely localization, tracking, occupancy and social interaction.
