A Child's-Eye View: An Examination of Point-of-View Camera Use in Four Informal Education Settings

A point-of-view (POV) camera is a video recording device attached to the person of a research participant. The cameras collect observational data from the individual wearing them and those in close proximity. The cameras can be used to collect data that provide researchers with an immersive view of visitor experience by documenting visits from the perspective of the individual. The purpose of this article is to outline the benefits and weaknesses of using POV cameras for answering broad visitor studies research questions, compare their use to other common methods for visitor studies research, and examine their use within four informal educational settings—a zoo, a museum exhibit, a bus tour, and an afterschool program. In particular, the POV cameras are useful for capturing data beyond a single exhibit, recording the dialogue and gestures of individual visitors, and documenting interactions among group members. POV cameras may be especially useful for answering questions about hands-on activities such as building or tinkering. Limitations that should be considered when attempting to use POV cameras include participants tampering with the recording, the inability to see facial expressions, and the limited angle of captured video. Care should also be taken to minimize the discomfort of visitors in studies utilizing POV cameras.     

Contributions of Head-Mounted Cameras to Studying the Visual Environments of Infants and Young Children

Head-mounted video cameras (with and without an eye camera to track gaze direction) are being increasingly used to study infants’ and young children's visual environments and provide new and often unexpected insights about the visual world from a child's point of view. The challenge in using head cameras is principally conceptual and concerns the match between what these cameras measure and the research question. Head cameras record the scene in front of faces and thus answer questions about those head-centered scenes. In this “Tools of the Trade” article, we consider the unique contributions provided by head-centered video, the limitations and open questions that remain for head-camera methods, and the practical issues of placing head cameras on infants and analyzing the generated video.     

Robust anger: Recognition of deteriorated dynamic bodily emotion expressions

In two studies, the robustness of anger recognition of bodily expressions is tested. In the first study, video recordings of an actor expressing four distinct emotions (anger, despair, fear, and joy) were structurally manipulated as to image impairment and body segmentation. The results show that anger recognition is more robust than other emotions to image impairment and to body segmentation. Moreover, the study showed that arms expressing anger were more robustly recognised than arms expressing other emotions. Study 2 added face blurring as a variable to the bodily expressions and showed that it decreased accurate emotion recognition—but more for recognition of joy and despair than for anger and fear. In sum, the paper indicates the robustness of anger recognition in multileveled deteriorated bodily expressions.     

Image processing for improved eye-tracking accuracy

Video cameras provide a simple, noninvasive method for monitoring a subject’s eye movements. An important concept is that of the resolution of the system, which is the smallest eye movement that can be reliably detected. While hardware systems are available that estimate direction of gaze in real time from a video image of the pupil, such systems must limit image processing to attain real-time performance and are limited to a resolution of about 10 arc minutes. Two ways to improve resolution are discussed. The first is to improve the image processing algorithms that are used to derive an estimate. Offline analysis of the data can improve resolution by at least one order of magnitude for images of the pupil. A second avenue by which to improve resolution is to increase the optical gain of the imaging setup (i.e., the amount of image motion produced by a given eye rotation). Ophthalmoscopic imaging of retinal blood vessels provides increased optical gain and improved immunity to small head movements but requires a highly sensitive camera. The large number of images involved in a typical experiment imposes great demands on the storage, handling, and processing of data. A major bottleneck had been the real-time digitization and storage of large amounts of video imagery, but recent developments in video compression hardware have made this problem tractable at a reasonable cost. Images of both the retina and the pupil can be analyzed successfully using a basic toolbox of image-processing routines (filtering, correlation, thresholding, etc.), which are, for the most part, well suited to implementation on vectorizing supercomputers.     

Automatic recognition of eye blinking in spontaneously occurring behavior

Previous researchin automatic facial expression recognition has been limited to recognition of gross expression categories (e.g., joy or anger) in posed facial behavior under well-controlled conditions (e.g., frontal pose and minimal out-of-plane head motion). We have developed a system that detects a discrete and important facial action (e.g., eye blinking) in spontaneously occurring facial behavior that has been measured with a nonfrontal pose, moderate out-of-plane head motion, and occlusion. The system recovers three-dimensional motion parameters, stabilizes facial regions, extracts motion and appearance information, and recognizes discrete facial actions in spontaneous facial behavior. We tested the system in video data from a two-person interview. The 10 subjects were ethnically diverse, action units occurred during speech, and out-of-plane motion and occlusion from head motion and glasses were common. The video data were originally collected to answer substantive questions in psychology and represent a substantial challenge to automated action unit recognition. In analysis of blinks, the system achieved 98% accuracy.     

Lexico-semantic structure and the word-frequency effect in recognition memory

The word-frequency effect (WFE) in recognition memory refers to the finding that more rare words are better recognized than more common words. We demonstrate that a familiarity-discrimination model operating on data from a semantic word-association space yields a robust WFE in data on both hit rates and false-alarm rates. Our modeling results suggest that word frequency is encoded in the semantic structure of language, and that this encoding contributes to the WFE observed in item-recognition experiments.     

How a visual surveillance system hypothesizes how you behave

In the last few years, the installation of a large number of cameras has led to a need for increased capabilities in video surveillance systems. It has, indeed, been more and more necessary for human operators to be helped in the understanding of ongoing activities in real environments. Nowadays, the technology and the research in the machine vision and artificial intelligence fields allow one to expect a new generation of completely autonomous systems able to reckon the behaviors of entities such as pedestrians, vehicles, and so forth. Hence, whereas the sensing aspect of these systems has been the issue considered the most so far, research is now focused mainly on more newsworthy problems concerning understanding. In this article, we present a novel method for hypothesizing the evolution of behavior. For such purposes, the system is required to extract useful information by means of low-level techniques for detecting and maintaining track of moving objects. The further estimation of performed trajectories, together with objects classification, enables one to compute the probability distribution of the normal activities (e.g., trajectories). Such a distribution is defined by means of a novel clustering technique. The resulting clusters are used to estimate the evolution of objects’ behaviors and to speculate about any intention to act dangerously. The provided solution for hypothesizing behaviors occurring in real environments was tested in the context of an outdoor parking lot.     

Kinaesthetic judgements of the direction of line by young children

The ability of young children to make kinaesthetic judgements of direction of line has been studied under recognition and detection conditions. Some children were not more accurate than chance when they were required to indicate the same one of a pair of mirror image obliques lines over a series of trials; these children could, however, detect whether two obliques were oriented in the same direction or in different directions. These latter data suggest that the poor recognition of mirror image obliques arises from deficiencies in spatial categorizing and not in input coding. This conclusion is supported by the finding that children who performed poorly on the kinaesthetic recognition of obliques performed poorly on the visual recognition of these figures.     

Confidence–Accuracy Calibration with General Knowledge and Eyewitness Memory Cued Recall Questions

Summary: The confidence–accuracy relationship has primarily been studied through recognition tests and correlation analysis. However, cued recall is more ecological from a forensic perspective. Moreover, there may be more informative ways of analysing the confidence–accuracy relationship than correlations. In the present study, participants viewed a video of a bank robbery and were asked cued recall questions covering general knowledge and the video itself. Confidence ratings were collected, and correlations, calibration and discrimination measures were calculated. All measures indicated a strong confidence–accuracy relationship that was better for general knowledge than eyewitness memory questions. However, there were no differences in confidence ratings for correct answers, suggesting that the differences could be limited to the evaluation of incorrect answers. We concluded that confidence may be a good marker for accuracy with cued recall, but that further research using ecological tests and more informative data analysis techniques is needed. Copyright © 2011 John Wiley & Sons, Ltd.     

双模态情感分析的弹幕网络视频平台营销策略

随着互联网飞跃发展, 弹幕视频应运而生。这种新型的用户与视频交互方式具有新特性, 如用户情感表达实时动态性、情感分布多峰性。同时, 新特性也给实际研究工作带来挑战, 如用户画像刻画难度增大, 视频推荐和广告推送所需精度提高。现有研究尚未对弹幕视频的新特性进行深入分析, 也没有充分挖掘其本身所蕴含的学术研究价值。本文利用深度学习、自然语言处理技术、系统动力学方法, 结合心理学、市场营销学等多学科交叉前沿知识, 从数据驱动角度对弹幕视频数据进行分析和建模, 深度挖掘视频大数据潜在的商业价值。重点研究弹幕与视频双模态融合的情感识别方法; 构建带有用户情感特征的动态用户画像, 并建立基于用户画像的网络视频粘性营销机制; 分析用户情感与视频广告插播方式的相关性, 提出视频广告动态插播策略。丰富现有研究的同时, 为网络视频企业准确定位与分析用户需求, 创建高品质的智能营销平台供理论与决策支持。     

Chronic exposure to violent video games is not associated with alterations of emotional memory

Although acute effects of violent video game (VVG) exposure on affect and behaviour have been studied extensively, less is known about VVG effects on cognition. The present study examined whether chronic exposure to VVGs was associated with alterations in emotional long‐term memory. Participants completed an old‐new recognition task with 300 pictures of scenes ranging in emotion (negative, neutral and positive). We analysed accuracy and reaction time data using diffusion modelling to test a desensitization hypothesis. According to this hypothesis, VVG players would show reduced memory or a less liberal response bias for negative stimuli, compared with nonplayers. Contrary to the desensitization hypothesis, VVG exposure was not associated with differences in memory or response bias. This result suggests that, unlike other cognitive domains, long‐term memory may be robust to deleterious influences of chronic VVG exposure. Copyright © 2010 John Wiley & Sons, Ltd.     

A holistic account of the own-race effect in face recognition: evidence from a cross-cultural study

A robust finding in the cross-cultural research is that people's memories for faces of their own race are superior to their memories for other-race faces. However, the mechanisms underlying the own-race effect have not been well defined. In this study, a holistic explanation was examined in which Caucasian and Asian participants were asked to recognize features of Caucasian and Asian faces presented in isolation and in the whole face. The main finding was that Caucasian participants recognized own-race faces more holistically than Asian faces whereas Asian participants demonstrated holistic recognition for both own-race and other-race faces. The differences in holistic recognition between Caucasian and Asian participants mirrored differences in their relative experience with own-race and other-race faces. These results suggest that the own-race effect may arise from the holistic recognition of faces from a highly familiar racial group.     

Face Recognition in Poor-Quality Video; Evidence From Security Surveillance

Security surveillance systems often produce poor-quality video, and this may be problematic in gathering forensic evidence. We examined the ability of subjects to identify target people captured by a commercially available video security device. In Experiment 1, subjects personally familiar with the targets performed very well at identifying them, but subjects unfamiliar with the targets performed very poorly. Police officers with experience in forensic identification performed as poorly as other subjects unfamiliar with the targets. In Experiment 2, we asked how familiar subjects can perform so well. Using the same video device, we edited clips to obscure the head, body, or gait of the targets. Obscuring body or gait produced a small decrement in recognition performance. Obscuring the targets' heads had a dramatic effect on subjects' ability to recognize the targets. These results imply that subjects recognized the targets' faces, even in these poor-quality images.     

On Distinguishing Epistemic from Pragmatic Action

We present data and argument to show that in Tetris—a real-time, interactive video game—certain cognitive and perceptual problems are more quickly, easily, and reliably solved by performing actions in the world than by performing computational actions in the head alone. We have found that some of the translations and rotations made by players of this video game are best understood as actions that use the world to improve cognition. These actions are not used to implement a plan, or to implement a reaction; they are used to change the world in order to simplify the problem-solving task. Thus, we distinguish pragmatic actions—actions performed to bring one physically closer to a goal—from epistemic actions—actions performed to uncover informatioan that is hidden or hard to compute mentally. To illustrate the need for epistemic actions, we first develop a standard information-processing model of Tetris cognition and show that it cannot explain performance data from human players of the game—even when we relax the assumption of fully sequential processing. Standard models disregard many actions taken by players because they appear unmotivated or superfluous. However, we show that such actions are actually far from superfluous; they play a valuable role in improving human performance. We argue that traditional accounts are limited because they regard action as having a single function: to change the world. By recognizing a second function of action—an epistemic function—we can explain many of the actions that a traditional model cannot. Although our argument is supported by numerous examples specifically from Tetris, we outline how the new category of epistemic action can be incorporated into theories of action more generally.     

Recognition of all basic emotions varies in accuracy and reaction time: A new verbal method of measurement

To study different aspects of facial emotion recognition, valid methods are needed. The more widespread methods have some limitations. We propose a more ecological method that consists of presenting dynamic faces and measuring verbal reaction times. We presented 120 video clips depicting a gradual change from a neutral expression to a basic emotion (anger, disgust, fear, happiness, sadness and surprise), and recorded hit rates and reaction times of verbal labelling of emotions. Our results showed that verbal responses to six basic emotions differed in hit rates and reaction times: happiness > surprise > disgust > anger > sadness > fear (this means these emotional responses were more accurate and faster). Generally, our data are in accordance with previous findings, but our differentiation of responses is better than the data from previous experiments on six basic emotions.     

Predictive coding accelerates word recognition and learning in the early stages of language development

The ability to predict future events in the environment and learn from them is a fundamental component of adaptive behavior across species. Here we propose that inferring predictions facilitates speech processing and word learning in the early stages of language development. Twelve‐ and 24‐month olds’ electrophysiological brain responses to heard syllables are faster and more robust when the preceding word context predicts the ending of a familiar word. For unfamiliar, novel word forms, however, word‐expectancy violation generates a prediction error response, the strength of which significantly correlates with children's vocabulary scores at 12 months. These results suggest that predictive coding may accelerate word recognition and support early learning of novel words, including not only the learning of heard word forms but also their mapping to meanings. Prediction error may mediate learning via attention, since infants’ attention allocation to the entire learning situation in natural environments could account for the link between prediction error and the understanding of word meanings. On the whole, the present results on predictive coding support the view that principles of brain function reported across domains in humans and non‐human animals apply to language and its development in the infant brain. A video abstract of this article can be viewed at: http://hy.fi/unitube/video/e1cbb495-41d8-462e-8660-0864a1abd02c . [Correction added on 27 January 2017, after first online publication: The video abstract link was added.]     

Intervention or Involvement: A Video Observational Analysis of Bouncers in Aggressive Encounters

ABSTRACT

Little is known about how bouncer–patron interactions may influence a bouncer’s use of physical aggression. To address this gap, we offer a micro-interactional analysis examining real-life aggressive bouncer behavior captured by venue surveillance cameras. Quantitative results show that bouncer physical aggression is associated with interactions in which bouncers are directly involved as a conflict party, but not with interactions where they solely intervene as a third-party. Further, a qualitative analysis of emotional cues identifies anger as a plausible mechanism underpinning bouncer aggression. We consider the implications of these findings for night-time economy violence prevention strategies and discuss the relevance of video data for barroom research.