Deep discriminative models (DDMs), e.g. deep regression forests, deep neural decision forests, have been extensively studied recently to solve problems like facial age estimation, head pose estimation, gaze estimation and so forth. Such problems are challenging in part because a large amount of effective training data without noise and bias is often not available. While some progress has been achieved through learning more discriminative features, or reweighting samples, we argue what is more desirable is to learn gradually to discriminate like human beings. Then, we resort to self-paced learning (SPL). But a natural question arises: can self-paced regime lead DDMs to achieve more robust and less biased solutions? A serious problem with SPL, which is firstly discussed by this work, is it tends to aggravate the bias of solutions, especially for obvious imbalanced data. To this end, this paper proposes a new self-paced paradigm for deep discriminative model, which distinguishes noisy and underrepresented examples according to the output likelihood and entropy associated with each example, and tackle the fundamental ranking problem in SPL from a new perspective: fairness. This paradigm is fundamental, and could be easily combined with a variety of DDMs. Extensive experiments on three computer vision tasks, i.e., facial age estimation, head pose estimation and gaze estimation, demonstrate the efficacy of our paradigm. The code in Pytorch is available at https: //github.com/learninginvision/SPU. To the best of our knowledge, our work is the first paper in the literature of SPL that considers ranking fairness for self-paced regime construction.

Facial age estimation is an important and challenging problem in computer vision. Existing approaches usually employ deep neural networks (DNNs) to fit the mapping from facial features to age, even though there exist some noisy and confusing samples. We argue that it is more desirable to distinguish noisy and confusing facial images from regular ones, and alleviate the interference arising from them. To this end, we propose self-paced deep regression forests (SP-DRFs) -a gradual learning DNNs framework for age estimation. As the model is learned gradually, from simplicity to complexity, it tends to emphasize more on reliable samples and avoid bad local minima. Moreover, the proposed capped-likelihood function helps to exclude noisy samples in training, rendering our SP-DRFs significantly more robust. We demonstrate the efficacy of SP-DRFs on Morph II and FG-NET datasets, where our model achieves state-of-the-art performance.

Deep discriminative models (e.g. deep regression forests, deep Gaussian process) have been extensively studied recently to solve problems such as facial age estimation and head pose estimation. Most existing methods pursue to achieve robust and unbiased solutions through either learning more discriminative features, or weighting samples. We argue what is more desirable is to gradually learn to discriminate like our human being, and hence we resort to self-paced learning (SPL). Then, a natural question arises: can self-paced regime guide deep discriminative models to obtain more robust and less unbiased solutions? To this end, this paper proposes a new deep discriminative model -self-paced deep regression forests considering sample uncertainty (SPUDRFs). It builds up a new self-paced learning paradigm: easy and underrepresented samples first. This paradigm could be extended to combine with a variety of deep discriminative models. Extensive experiments on two computer vision tasks, i.e., facial age estimation and head pose estimation, demonstrate the efficacy of SPUDRFs, where state-of-the-art performances are achieved.