Age Sensitivity of Face Recognition Algorithms

This paper investigates the performance degradation of facial recognition systems due to the influence of age. A comparative analysis of verification performance is conducted for four subspace projection techniques combined with four different distance metrics. The experimental results based on a subset of the MORPH-II database show that the choice of subspace projection technique and associated distance metric can have a significant impact on the performance of the face recognition system for particular age groups

Biometric information analyses using computer vision techniques.

Biometric information analysis is derived from the analysis of a series of physical and biological characteristics of a person. It is widely regarded as the most fundamental task in the realms of computer vision and machine learning. With the overwhelming power of computer vision techniques, biometric information analysis have received increasing attention in the past decades. Biometric information can be analyzed from many sources including iris, retina, voice, fingerprint, facial image or even the way one walks with. Facial image and gait, because of their easy availability, are two preferable sources of biometric information analysis. In this thesis, we investigated the development of most recent computer vision techniques and proposed various state-of-the-art models to solve the four principle problems in biometric information analysis including the age estimation, age progression, face retrieval and gait recognition. For age estimation, the modeling has always been a challenge. Existing works model the age estimation problem as either a classification or a regression problem. However, these two types of models are not able to reveal the intrinsic nature of human age. To this end, we proposed a novel hierarchical framework and a ordinal metric learning based method. In the hierarchical framework, a random forest based clustering method is introduced to find an optimal age grouping protocol. In the ordinal metric learning approach, the age estimation is solved by learning an subspace where the ordinal structure of the data is preserved. Both of them have achieved state-of-the-art performance. For face retrieval, specifically under a cross-age setting, we first proposed a novel task, that is given two images, finding the target image which is supposed to have the same identity with the first input and the same age with the second input. To tackle this task, we proposed a joint manifold learning method that can disentangle the identity with the age information. Accompanied with two independent similarity measurements, the retrieval can be easily performed. For aging progression, we also proposed a novel task that has never been considered. We devoted to fuse the identity of one image with the age of another image. By proposing a novel framework based on generative adversarial networks, our model is able to generate close-to-realistic images. Lastly, although gait recognition is an ideal long-distance biometric information task that makes up the shortfall of facial image, existing works are not able to handle large scale data with various view angles. We proposed a generative model to solve this term and achieved promising results. Moreover, our model is able to generate evidences for forensic usage

Change blindness: eradication of gestalt strategies

Arrays of eight, texture-defined rectangles were used as stimuli in a one-shot change blindness (CB) task where there was a 50% chance that one rectangle would change orientation between two successive presentations separated by an interval. CB was eliminated by cueing the target rectangle in the first stimulus, reduced by cueing in the interval and unaffected by cueing in the second presentation. This supports the idea that a representation was formed that persisted through the interval before being 'overwritten' by the second presentation (Landman et al, 2003 Vision Research 43149–164]. Another possibility is that participants used some kind of grouping or Gestalt strategy. To test this we changed the spatial position of the rectangles in the second presentation by shifting them along imaginary spokes (by ±1 degree) emanating from the central fixation point. There was no significant difference seen in performance between this and the standard task [F(1,4)=2.565, p=0.185]. This may suggest two things: (i) Gestalt grouping is not used as a strategy in these tasks, and (ii) it gives further weight to the argument that objects may be stored and retrieved from a pre-attentional store during this task

Information and communication technologies and geographic concentration of manufacturing industries: evidence from China

Using the 2004 China economic census database, this paper examines the impact of information and communication technologies (ICT) on the geographic concentration of manufacturing industries, controlling for other determinants of industrial agglomeration. Higher geographic concentration is found consistently in industries where ICT are more widely adopted, and the association is stronger at higher geographic levels. Furthermore, young firms that have adopted ICT, although they are more footloose, contribute to industrial agglomeration. High-tech industries with advanced ICT also tend to agglomerate. Contrary to the prevalent argument that ICT lead to more dispersion, our study suggests that ICT promote industrial agglomeration.Information and communication technologies; Geographic concentration; Agglomeration; China

Migrant Youths' Educational Achievement: The Role of Institutions

We use 2009 Programme of International Student Assessment (PISA) data to link institutional arrangements in OECD countries to the disparity in reading, math, and science test scores for migrant and native-born students. We find that achievement gaps are larger for those migrant youths who arrive later and for those who do not speak the test language at home. Institutional arrangements often serve to mitigate the achievement gaps of some migrant students while leaving unaffected or exacerbating those of others. For example, earlier school starting ages help migrant youths in some cases, but by no means in all. Limited tracking on ability appears beneficial for migrants' relative achievement, while complete tracking and a large private school sector appear detrimental. Migrant students' achievement relative to their native-born peers suffers as educational spending and teachers' salaries increase, but is improved when examination is a component of the process for evaluating teachers.Migrant Youths; PISA Test Scores; Schools; Institutions; Academic Achievement.

Information and communication technologies and geographic concentration of manufacturing industries: Evidence from China

Using the 2004 China economic census database, this paper examines the impact of information and communication technologies (ICT) on the geographic concentration of manufacturing industries, controlling for other determinants of industrial agglomeration. Higher geographic concentration is found consistently in industries where ICT are more widely adopted, and the association is stronger at higher geographic levels. Furthermore, young firms that have adopted ICT, although they are more footloose, contribute to industrial agglomeration. High-tech industries with advanced ICT also tend to agglomerate. Contrary to the prevalent argument that ICT lead to more dispersion, our study suggests that ICT promote industrial agglomeration.Information and communication technologies; Geographic concentration; Agglomeration