We present a new dataset of "free roaming" (FR) and "targeted roaming" (TR): a pool of 41 participants is asked to walk around a university campus (FR) or is asked to find a particular room within a library (TR). Eye movements are recorded using a commodity wearable eye tracker (Pupil Labs Neon at 200Hz). On this dataset we investigate the accuracy of user identification using a previously known machine learning pipeline where a Radial Basis Function Network (RBFN) is used as classifier. Our highest accuracies are 87.3% for FR and 89.4% for TR. This should be compared to 95.3% which is the (corresponding) highest accuracy we are aware of (achieved in a laboratory setting using the "RAN" stimulus of the BioEye 2015 competition dataset). To the best of our knowledge, our results are the first that study user identification in a non laboratory setting; such settings are often more feasible than laboratory settings and may include further advantages. The minimum duration of each recording is 263s for FR and 154s for TR. Our best accuracies are obtained when restricting to 120s and 140s for FR and TR respectively, always cut from the end of the trajectories (both for the training and testing sessions). If we cut the same length from the beginning, then accuracies are 12.2% lower for FR and around 6.4% lower for TR. On the full trajectories accuracies are lower by 5% and 52% for FR and TR. We also investigate the impact of including higher order velocity derivatives (such as acceleration, jerk, or jounce).

翻译：我们提出了一个包含“自由漫游”（FR）和“目标导向漫游”（TR）的新数据集：41名参与者被要求在大学校园内自由行走（FR），或在图书馆内寻找特定房间（TR）。眼动数据通过商用可穿戴眼动追踪器（Pupil Labs Neon，采样率200Hz）记录。基于该数据集，我们采用先前已知的机器学习流程（以径向基函数网络（RBFN）作为分类器）探究用户识别的准确率。在FR和TR任务中，我们取得的最高准确率分别为87.3%和89.4%。相比之下，已知的最高对应准确率为95.3%（在实验室环境下使用BioEye 2015竞赛数据集的“RAN”刺激源实现）。据我们所知，本研究首次在非实验室环境下探索用户识别问题——这类环境通常比实验室设置更具可行性，且可能具备额外优势。每个记录的最短持续时间为：FR任务263秒，TR任务154秒。当对FR和TR分别截取轨迹末尾的120秒和140秒数据时，我们获得了最佳准确率（训练和测试阶段均采用相同截取方式）。若改为截取轨迹起始处相同长度的数据，FR和TR的准确率分别降低12.2%和6.4%。当使用完整轨迹时，FR和TR的准确率分别降低5%和52%。此外，我们还研究了引入高阶速度导数（如加速度、加加速度、弹跳度）的影响。