A gaze interactive assembly instruction with pupillometric recording.

This paper presents a study of a gaze interactive digital assembly instruction that provides concurrent logging of pupil data in a realistic task setting. The instruction allows hands-free gaze dwells as a substitute for finger clicks, and supports image rotation as well as image zooming by head movements. A user study in two LEGO toy stores with 72 children showed it to be immediately usable by 64 of them. Data logging of view-times and pupil dilations was possible for 59 participants. On average, the children spent half of the time attending to the instruction (S.D. 10.9%). The recorded pupil size showed a decrease throughout the building process, except when the child had to back-step: a regression was found to be followed by a pupil dilation. The main contribution of this study is to demonstrate gaze-tracking technology capable of supporting both robust interaction and concurrent, non-intrusive recording of gaze- and pupil data in-the-wild. Previous research has found pupil dilation to be associated with changes in task effort. However, other factors like fatigue, head motion, or ambient light may also have an impact. The final section summarizes our approach to this complexity of real-task pupil data collection and makes suggestions for how future applications may utilize pupil information.

The deployment of conditional probability distributions for death time estimation.

The temperature based algorithm known as the Nomogram Method for the determination of a 95.45% death-time interval can be combined with non-temperature based (NTB) findings in the so called Compound Method (CM). The impact of such integration on the probability yielded by the resulting interval has however neither been described nor exploited. In fact the interval after integration of NTB findings rarely yields 95.45% probability. We present a method, based on the conditional probability distribution that can be calculated if the NTB findings are taken into account, which ensures the probability inside the interval to be 95.45%. The method was successfully applied to a set of 53 cases published by Henssge et al. and led to a reduction of the interval width up to more than 15% compared to the CM interval, whereas in other cases the interval width increased due to probability content of the CM intervals below 95.45%. A spreadsheet file in which the method proposed in this paper is implemented can be obtained upon email request from the authors.