Academic and research departmentsDepartment of Music and Media, Centre for Vision, Speech and Signal Processing (CVSSP).
Statistics, machine learning, digital signal processing, deep learning, artificial intelligence, music and audio, psychology, mental health, engineering, computer vision.
Incorporating Weak Supervision to Encourage Disentanglement,15th IEEE International Conference on Automatic Face and Gesture Recognition
to generate representational latent embeddings. Previous research has highlighted the benefits of achieving representations that are disentangled, particularly for downstream tasks. However, there is some debate about how to encourage disentanglement with VAEs, and evidence indicates that existing implementations do not achieve disentanglement consistently. The evaluation of how well a VAE?s latent space has been disentangled is often evaluated against our subjective expectations of which attributes should be disentangled for a given problem. Therefore, by definition, we already have domain knowledge of what should be achieved and yet we use
unsupervised approaches to achieve it. We propose a weakly supervised approach that incorporates any available domain knowledge into the training process to form a Gated-VAE. The process involves partitioning the representational embedding
and gating backpropagation. All partitions are utilised on the forward pass but gradients are backpropagated through different partitions according to selected image/target pairings. The approach can be used to modify existing VAE models such as beta-VAE, InfoVAE and DIP-VAE-II. Experiments demonstrate that using gated backpropagation, latent factors are represented in their intended partition. The approach is applied to images of faces for the purpose of disentangling
head-pose from facial expression. Quantitative metrics
show that using Gated-VAE improves average disentanglement, completeness and informativeness, as compared with un-gated implementations. Qualitative assessment of latent traversals
demonstrate its disentanglement of head-pose from expression, even when only weak/noisy supervision is available.
projective mapping tasks with auditory stimuli,Journal of the Audio Engineering Society Audio Engineering Society
task (PDT) and a projective mapping task (PMT). For a set of unambiguous, synthetic, auditory stimuli the aim was to determine: whether the PMT limits the recovered dimensionality to two dimensions; how subjects respond using PMT?s two-dimensional response format; the
relative time required for PDT and PMT; and hence whether PMT is an appropriate alternative
to PDT for experiments involving auditory stimuli. The results of both Multi-Dimensional
Scaling (MDS) analyses and Multiple Factor Analyses (MFA) indicate that, with multiple participants,
PMT allows for the recovery of three meaningful dimensions. The results from the MDS and MFA analyses of the PDT data, on the other hand, were ambiguous and did not
enable recovery of more than two meaningful dimensions. This result was unexpected given
that PDT is generally considered not to limit the dimensionality that can be recovered. Participants
took less time to complete the experiment using PMT compared to PDT (a median
ratio of approximately 1:4), and employed a range of strategies to express three perceptual
dimensions using PMT?s two-dimensional response format. PMT may provide a viable and
efficient means to elicit up to 3-dimensional responses from listeners.
MJ Vowels, KP Mark, LM Vowels, ND Wood (2018) Using spectral and cross-spectral analysis to identify patterns and synchrony in couples’ sexual desire, PloS one 13 (10)
Vowels Matthew, Camgöz Necati Cihan, Bowden Richard (2020) NestedVAE: Isolating Common Factors via Weak Supervision, IEEE Conference on Computer Vision and Pattern Recognition
Peter Hilpert, Timothy R Brick, Christoph Flueckiger, Matthew Vowels, Eva Ceuleman, Peter Kuppens, Laura Sels (2019) What Can Be Learned From Couple Research: Examining Emotional Co-Regulation Processes in Face-to-Face Interactions, Journal of Counselling Psychology
B Ross, J Gale, K Wickrama, J Goetz, MJ Vowels (2019) The Impact of Family Economic Strain On Work-Family Conflict, Marital Support, Marital Quality, and Marital Stability During the Middle Years, Journal of Personal Finance 18 (2)