# symmetryinduced_disentanglement_on_graphs__ee0ddb7a.pdf Symmetry-induced Disentanglement on Graphs Giangiacomo Mercatali University of Manchester André Freitas Idiap Research Institute University of Manchester Vikas Garg Yai Yai Ltd and Aalto University vgarg@csail.mit.edu Learning disentangled representations is important for unraveling the underlying complex interactions between latent generative factors. Disentanglement has been formalized using a symmetry-centric notion for unstructured spaces, however, graphs have eluded a similarly rigorous treatment. We fill this gap with a new notion of conditional symmetry for disentanglement, and leverage tools from Lie algebras to encode graph properties into subgroups using suitable adaptations of generative models such as Variational Autoencoders. Unlike existing works on disentanglement, the proposed models segregate the latent space into uncoupled and entangled parts. Experiments on synthetic and real datasets suggest that these models can learn effective disengaged representations, and improve performance on downstream tasks such as few-shot classification and molecular generation. 1 Introduction Disentanglement represents a fundamental desideratum in learning with limited supervision because it captures information about the salient (or explanatory) factors of variation in the data, and isolates information about each specific factor in only a few dimensions, thus unraveling the interactions underlying complex data [2, 59]. Disentangled representations have often been deemed responsible for providing neural models with the ability to improve performance on real-world downstream tasks [2, 20, 36, 58, 59]. Empirically, they have been shown to enable, or facilitate, critical properties such as sample efficiency [21] and generalization [32, 42, 69]. An interesting perspective on disentanglement has been recently proposed by Higgins et al. [20]. Specifically, they advocate viewing disentanglement as decomposition of the latent space of embeddings into subspaces, each of which can be transformed independently under the action of a single subgroup specific to the subspace, without affecting others. These subgroups arise, in turn, from the decomposition of a symmetry group. This formalism bestows several benefits, e.g., it (a) aligns with the idea that auxiliary information can be exploited for imposing a structure on the latent space [25, 40], and (b) leads to a rigorous theoretical framework for analyzing disentangled models [64, 70], e.g., those based on Variational Autoencoders (VAEs) [27, 50]. While symmetry groups provide a suitable tool both for formalizing [20] and learning [57, 64, 70] disentangled representations in unstructured domains, these techniques have not been investigated in the context of more general and complex data such as graphs. Furthermore, most works on disentanglement for graphs [1, 16, 31, 35, 38, 65] are not designed for generative settings, and the existing deep generative models (DGMs) for graph disentanglement such as [10, 17, 56] do not consider group symmetries. Note that differently from other definitions of disentanglement [2, 9, 11], leveraging group symmetries for disentanglement may unravel fundamental connections across several approaches based on graph neural networks (GNNs), i.e., the state-of-the-art models for embedding graphs [3, 5, 8, 13, 15, 39, 63]. first-name.last-name@postgrad.manchester.ac.uk 36th Conference on Neural Information Processing Systems (Neur IPS 2022). We, therefore, pursue two main goals in this work: (a) providing a rigorous symmetry-based formalism for disentanglement on graphs, and 2) designing novel neural architectures that are able to leverage symmetry groups to learn disengaged representations for graphs. However, accomplishing these objectives requires overcoming some challenges. In particular, graphs often abstract complex interactions, so the underlying latent space may not factorize completely into only disentangled subspaces. Thus, the symmetry-based formalism introduced in [20] does not suffice for graphs. Therefore, we introduce a new, more flexible notion of conditional disentanglement, advocating segregating the latent space into uncoupled and entangled parts. Translating this idea into an efficient algorithm requires further work, and we appeal to a Lie algebra based parameterization to encode the graph properties into subgroups. Contributions. Our contributions can be summarized as follows: a novel notion of symmetry-induced conditional disentanglement (Section 3.1) that generalizes the previous definition from [20] (which we call unconditional disentanglement); a parameterization centered on Lie algebra based on the intuition that each separable generative factor can correspond to a Lie algebra coordinate element, and control a single graph property (Section 3.2); two algorithms for Symmetry-Induced Disentanglement under unconditional (SIDU) and conditional (SIDC) settings, both using a two-level variational auto-encoding mechanism, namely, one level for the data and other for symmetry group representation (Section 4); and a systematic evaluation on several disentanglement metrics [7, 11, 19, 26, 44]. The results demonstrate that the proposed models can outperform contemporary GNN baselines [38, 65]; successfully learn to decouple the entangled part of latent space from the disentangled parts (Section 5.1); and improve performance on downstream tasks such as few-shot classification, compression (Section 5.2) and molecular graph generation (Section 5.3). We begin with a review of the relevant literature, and then proceed to the proposed framework. 2 Related work Symmetry-based disentanglement (SBD). Initial works on SBD, such as Caselles-Dupré et al. [6], Quessard et al. [48], propose to use reinforcement learning to achieve irreducible representations of group elements through observation of action transitions. Painter et al. [44] introduce a VAE method that does not require labelled action-transition pairs, and demonstrate its validity within the environment from Caselles-Dupré et al. [6]. More recently, some algebraic approaches have been introduced. Zhu et al. [70] propose to decompose a Lie group into multiple subgroups, and enforce commutativity and independence between subgroups. Yang et al. [64] impose a cyclic group structure, encouraging the group to be isomorphic to the ground truth. Bouchacourt et al. [4] invoke group representation theory for defining distributed latent operators that are able to learn disentangled representations. Tonnaer et al. [57] provide a new metric for evaluation, and a VAE-based model for learning symmetry-based disentangled representations. Some works leverage data manifolds for SBD. For example, Fumero et al. [12] view disentanglement as a product of low-dimensional sub-manifolds underlying the data space, such that each sub-manifold encodes an explainable data factor. Pfau et al. [46] propose a non-parametric algorithm that aims to discover a decomposition of the data manifold by investigating its holonomy group. Other works explore SBD as well. For instance, Higgins et al. [22] demonstrate the importance of symmetry transformations and disentangled representation learning in the context of neuroscience. Wang et al. [61] design a contrastive self-supervised learning method that iteratively updates a partition, modeled as a symmetry group, until the considered factor is invariant. Disentangled GNNs. To our knowledge, Ma et al. [38] provide the first graph disentanglement approach, which involves a routing mechanism aimed at separating the underlying factors. More recently, Yang et al. [65] exploit an attention mechanism for GNNs, and provide two evaluation metrics for disentanglement on graphs. Liu et al. [35] achieve disentanglement by encouraging independence in the latent space, while Bae and Jeon [1] propose a method for disentangling multirelational graphs motivated by an application on pedestrian trajectory prediction. Li et al. [31] provides a contrastive framework for disentangling the latent factors in GNNs. Differently from these methods, we provide a formal definition of disentanglement for graphs, and leverage symmetry groups in a generative model setting. Graph DGMs. Wu et al. [62], Yu et al. [68] propose VAE-based Information Bottleneck methods for improving the performance of GNNs on classification tasks, by learning minimal sufficient representations. The work by Simonovsky and Komodakis [55] aims to generate molecular graphs using graph VAEs. Liu et al. [34] adapt VAEs for conditioning molecule generation on specific properties. You et al. [67] propose a deep autoregressive model that learns to generate graphs by training on a representative set of graphs and decomposes the graph generation process into a sequence of node and edge formations. Du et al. [10] propose a DGM for spatio-temporal graphs, and Guo et al. [18] investigate DGMs with spatial networks. Finally, Guo et al. [17] and Stoehr et al. [56] investigate disentangled representations with graph VAEs. 3 Proposed framework In Section 3.1 we review the unconditional symmetry-induced disentanglement, and propose a new definition of conditional disentanglement. In Section 3.2 we extend these notions to graphs. Finally, in Section 3.3, we describe additional loss terms to encourage disentanglement. 3.1 Symmetry-based disentanglement Definition 1 (Unconditional symmetry-based disentanglement [20]). Consider a generative process b = W O mapping the world states W into observations (i.e. data) O, and an inference process h = O Z mapping the data into a latent vector space. By composing b and h, we obtain f = h b such that f : W Z. Given group actions on W, i.e., W : G W W and on Z, i.e., Z : G Z Z, the function f is said to be equivariant between the actions on W and Z if the actions commute with f. We can express this equivariance mathematically as g Z f(w) = f(g W w), g G, w W. Assuming that the symmetry group G can be decomposed into subgroups G1 . . . Gn, a vector representation Z is disentangled with respect to this decomposition if all of the following conditions hold: there is an action defined on the representation set Z : G Z Z, the map f : W Z is equivariant between the actions on W and Z, and there is a decomposition Z = Z1 Z2 . . . Zn such that each Zi is affected only by Gi and is invariant to (i.e., does not change due to) Gj for all j = i. Definition 1 does not allow any part of the latent vector space to be entangled, which is likely to be restrictive for complex applications. Therefore, we propose conditional disentanglement. Definition 2 (Conditional symmetry-based equivariance). Consider a generative process b = W E O mapping the disentangle-able world states W and non-disentangled states E into observations (i.e. data) O, and an inference process h = O Z mapping the data into a latent vector space. By composing b and h, we obtain f = b h, which maps W E to Z. Given group actions on W, namely, W : G W W and on Z, namely, Z : G Z Z, the function f is said to be conditionally equivariant between the actions on W and Z given E if the actions commute with f. That is, g Z f(w, e) = f(g W w, e), g G, w W, e E. This definition of conditional equivariance naturally leads to a new notion of conditional disentanglement using a characterization similar to the three conditions for the unconditional case. Specifically, we need to impose the condition that f is conditionally equivariant between the actions of W and Z given E (instead of simply being equivariant between the actions of W and Z). Note that while this definition results in a generalized framework for disentanglement, it does not directly translate into a learning algorithm. Toward that goal, we invoke tools from Lie algebra as described in the next section. 3.2 Disentanglement on graphs Here, we aim to instantiate Definition 1 and 2 in the context of models that encode graph-structured data. Drawing inspiration from the previous work on Lie groups and algebras for symmetry-induced disentangled VAEs by Zhu et al. [70], we develop a formalism for disentanglement on graphs induced by Lie groups. Lie groups and Lie algebras. A Lie group G is a group of continuous symmetries [52], and associated with a Lie algebra g, which is the tangent space to the identity element of G. We can thus parameterize a Lie algebra with a basis {Ai}k i=1, where every element in g can be written as A = A1t1 + . . . + Aktk using coordinates ti. Elements of the Lie algebra can be mapped back into the Lie group with a matrix exponential map exp : g G. We now provide some intuition into how we can connect the notion of a Lie group G with the definition of disentanglement in a graph network, by associating each Lie algebra coordinate ti with a generative factor. A latent representation ˆZ, obtained, e.g., from a graph encoder, is disentangled with respect to a Lie group G, if a change in the coordinate ti is associated with a change in only the ith component of ˆZ, i.e., only ˆzi. In other words, disentanglement entails that the semantics (t1, t2, . . . , tk) are equivariant with respect to the properties (ˆz1, ˆz2, . . . , ˆzk) that are being predicted. Next, we provide the formal definitions for unconditional and conditional graph disentanglement. The former expresses ˆZ as a function of T without accounting for Z, whereas the latter expresses ˆZ based on T after fixing an encoding Z. Definition 3 (Lie-algebra based unconditional graph disentanglement). The graph embedding ˆZ obtained by f( ˆZ|T) is unconditionally disentangled with respect to the Lie group coordinates T = {tj}k j=1 if the following hold: (a) there is a group action ˆ Z : G ˆZ ˆZ on ˆZ, (b) the map f = exp(A(T)) : T ˆZ is equivariant between actions on T and ˆZ, and (c) there is a decomposition ˆZ = ˆz1 ˆz2 . . . ˆzk, where each coordinate ti affects only the corresponding component ˆzi. Definition 4 (Lie-algebra based conditional graph disentanglement). The graph embedding ˆZ obtained by f( ˆZ|T, Z) is conditionally disentangled with respect to the Lie group coordinates T = {tj}k j=1 given Z if (a) there is a group action ˆ Z : G ˆZ ˆZ on ˆZ, (b) the map f : exp A(T) Z ˆZ is equivariant between actions on T and ˆZ for any fixed Z, and (c) exp A(T) Z factorizes into the product Qk i=1 exp(ti Ai) Z such that each component exp(ti Ai) is affected only by the corresponding coordinate ti for i {1, 2, . . . , k} for any fixed Z. 3.3 Disentanglement constraints It is known [64, 70] that a symmetry group parameterization is usually not sufficient for a group to be decomposed into subgroups that are parameterized independently by a single coordinate. Therefore, following Zhu et al. [70], we add two additional constraints for enforcing disentanglement. These constraints can be relaxed, and included in the loss function as regularization terms. Commutative penalty. We would like to enforce a coordinate ti to be identified by single group exp(ti Ai), and thus represent a single property variation in the data ˆzi. Mathematically, one can state this desideratum as an equivalence between the exponential map of the sum, and the product over exponential maps. [70] proved this to be achieved under commutativity over the Lie algebra basis. Namely, if Ai Aj = Aj Ai then exp Pk i=1 ti Ai = Qk i=1 exp(ti Ai). Hessian penalty Furthermore, disentanglement can be encouraged using a Hessian penalty [45] based on the fact the Hessian matrix with respect to a disentangled representation is always zero (owing to the independence between different dimensions). Zhu et al. [70] adapt this penalty in a Lie algebra parameterization setup, as Hij = δ2g(T ) δtiδtj where g(T) = exp Pk i=1 ti Ai , and show that if Ai Aj = 0 i, j then Hij = 0. Symmetry-Induced Disentanglement Conditional disentanglement Figure 1: Left (architecture): SID is composed of 4 blocks, i.e., 2 layers each for the auto-encoding modules for graph data and group structure. Middle (Egroup): the Lie algebra coordinates ti are obtained by applying k graph convolutional networks (GCNs) to the graph embedding Z. Right (Dgroup): the coordinates ti are combined with basis elements A to reconstruct the graph latent code. In the conditional case (red nodes) we further condition on Z, by taking the mean (µ) of Z and ˆZ, and passing µ through an activation function σ (Re Lu for our experiments). We propose Symmetry-Induced Disentanglement (SID), a VAE framework for graphs [28, 55] which encourages disentangled representations using a Lie group parameterization and two regularization losses (commutative and hessian penalties). The architecture is depicted in Figure 1. 4.1 Probabilistic formulation We use the following notation for model variables: latent graph embeddings Z (and ˆZ), graph features X, symmetry Lie group structure T, and the graph adjacency matrix A. We next derive lower bounds on log-likelihood for both the unconditional and conditional settings (see Appendix for details). Proposition 1 (Unconditional lower bound). Given two latent variables Z and T, we instantiate the unconditional disentanglement from Definition 3 with a probabilistic model that maximizes the log-likelihood of the graph data G = (X, A) by optimizing the following lower bound: Lu = Eq(Z|G)q(T |Z,A) log p(Z|T)p(G|Z) Eq(Z|G)KL(q(T|Z, A)||p(T)) Eq(Z|G) log q(Z|G) . (1) Proposition 2 (Conditional lower bound). We extend Proposition 1 to account for conditional disentanglement as defined in Definition 4. We obtain the following lower bound Lc = Eq(Z|G)q(T |Z,A) log p( ˆZ|T, Z)p(G| ˆZ) Eq(Z|G)KL(q(T|Z, A)||p(Z, T)) Eq(Z|G) log q(Z|G) . (2) Architecture. Propositions 1 and (2) are derived respectively in Appendix. The respective losses (1 and 2) are implemented with four neural network modules as follows. Two stochastic encoders (Egraph and Egroup) embed respectively the graph data G into a latent variable Z via q(Z|G), and Z into the Lie group coordinates T via q(T|Z). Two deterministic decoders (Dgroup and Dgraph) reconstruct, respectively, the graph embedding ˆZ from T via p( ˆZ|T) for the unconditional case, and the graph G from ˆZ via p(G| ˆZ). The decoder network Dgroup also plays a role in implementing the conditional lower bound, via p( ˆZ|Z, T), which computes ˆZ conditioned on Z and T. 4.2 Encoders Graph encoder. We first encode the graph features X and the adjacency matrix A in the latent space Z, using an inference network Egraph q(Z|X, A). Similarly to Kipf and Welling [28], we use a single 2-layer network, where the first layer leverages a graph convolutional network (GCN) to reduce the dimension of the graph features to the symmetry group size: X = GCN(X, A). The second layer computes the mean and variance vectors (µ = GCNµ(X, A), log σ = GCNσ(X, A)), which are then used to sample the latent variable Z from a Gaussian distribution with the reparameterization trick: q(Z|X, A) = N(Z|µ, diag(σ2)). Group encoder. We employ Egroup to map the latent vector Z into a vector T of k Lie algebra coordinates, where k is the subspace size (e.g., the number of disentangled elements). In our settings, each lie algebra coordinate {ti}k i=1 is the output of a GCN with two layers. The first one computes a graph embedding Z = GCN(Z, A), and the second one produces the vectors µ = GCNµ(Z, A), log σ = GCNσ(Z, A), which in turn yield produce {ti}k i=1 with the reparameterization trick. Finally, {ti}k i=1 are combined into a single tensor T using a multilayer perceptron (MLP): q(T|Z, A) = MLP(q(ti|Z, A)) with q(ti|Z, A) = N(ti|µi, diag(σ2 i )) for i = 1 . . . , k (3) 4.3 Decoders Group decoder. The module Dgroup reconstructs the latent variable ˆZ using a Lie group G and a Lie algebra g. Specifically, we first learn a Lie algebra basis element {Ai}k i=1 g for each coordinate ti. We then aggregate the coordinates ti and basis elements Ai with an exponential map, to obtain a group representation as p( ˆZ|T) = g(T) = exp(A(T)) where A(T) = Xk i=1 ti Ai for g G, A g . (4) The conditional version of Dgroup is obtained with a slight modification of Eq. 4: ˆZ is computed by feeding the mean between Z (e.g. the graph embeddings obtained from Egraph), and exp(A(T)) into a non-linear activation function σ such as Re LU: p( ˆZ|T, Z) = σ(mean[exp(A(T)), Z]), where Z = {zj}k j=1 . (5) Graph decoder. The network Dgraph reconstructs the graph data ˆG from the latents ˆZ. This is achieved by first passing the latent feature to a GCN layer that maps Z into a vector of the same dimension as the original feature vectors, and subsequently into a sigmoid activation function: p(A, X| ˆZ) = p(A, X|σ(GCN( ˆZ))) (6) 4.4 Training The proposed unconditional and conditional models are trained by optimizing the loss given by βL + λh + γc, where L is the lower bound from Eq. 1 (unconditional) or Eq. 2 (conditional), and h and c are respectively the hessian and commutative penalties, obtained as regularization terms adapting the implementation from Zhu et al. [70]. We provide insights into the effect of parameters on the models and their performance with an ablation study in Section 5.1. For neural architecture, we set each encoder and decoder to consist of 3 layers, where each layer takes as input the graph features from the previous layer. 5 Experiments We conducted extensive experiments that we decribe now. Section 5.1 evaluates the disentanglement capabilities of the models, Section 5.2 provides a compression and few-shots classification experiment, and Section 5.3 assesses the generation capabilities on molecular datasets. 5.1 Disentanglement evaluation We evaluate disentanglement with a) an ablation study for assessing our models components, b) qualitative investigations, and c) quantitative metrics. For metrics, we follow the evaluation protocols from Locatello et al. [36], which involve being able to randomly combine a number of generative factors to sample a new data. In our case, we provide the necessary generative factors to generate two types of synthetic random graphs (e.g. Erdos-Renyi and Watts-Strogatz). More details about our dataset construction procedure are provided in Appendix A. We compute 5 metrics, including β-VAE [19] (Beta), Factor VAE (FVM) [26], Mutual Information Gap (MIG) [7], DCI Disentanglement [11], and Factor Leakage (FL) [44]. Figure 2: Impact of single model components on disentanglement metrics. Ablation study. We start by evaluating the impact of our model components on the disentanglement metrics, by maintaining all parameters fixed, except from one that varies. We probe the effect from different group sizes, hessian penalties, commutative penalties, and subspace sizes. In Figure 2 we report the mean over 10 runs for our unconditional model on the synthetic Watts-Strogatz dataset. We observe that when the group size is increased, there is an improvement in disentanglement across all metrics, and this can be explained by the idea that with a larger group size, the subgroups, represented by the Lie algebra coordinate ti can control different data variations. The hessian penalty results to be effectively enhancing disentangled representations, while the commutative penalty is less effective, and we can explain this result because the former requires the Lie algebra basis elements to have mutual products of zeros while subgroup decomposition only requires their commutators to be zeros, which also confirms the results obtained for image datasets [70]. Correlation analysis. Following previous work [65, 38], we report the correlation matrix of the hidden graph features, the goal of which is to show whether the features capture mutually exclusive information, which is achieved when the there is a block-wise correlation pattern. In our models we use a group-size of 32 (to match with hidden features size of the other methods), a hessian penalty of 40 and commutative penalty of 5. In Figure 3 we note that both our SIDU and SIDC models achieve a block-wise correlation pattern, however the conditional version has also some other highlighted regions, because in this model involves fixing a latent vector Z to condition the reconstruction. As a result, the conditioning may be responsible for the visualized correlation on the hidden features. Figure 3: Correlation analysis Learned graph variations. In this experiment, we train the SIDC model on Watts-Strogatz (WS) random graphs, which have 3 generative factors, n for number of nodes, p for connectivity (the probability of rewiring each edge), and k for neighborhood (k nearest neighbors in a ring topology). We adapt our model to the visualization implementations provided by Stoehr et al. [56], which report adjacency matrices (black) and graph (white) information, where variations in node attribute values are indicated in blue. In Figure 4 we report the results for the SIDC model by projecting pairs of latent variable traversals to see how the factors vary, and we observe the following. 1) The variable z0 controls the node attribute value. For example, in adj01 we see the color changing from blue to white along the horizontal axis. 2) The variable z1 controls connectivity, for example in graph01, in the z1 axis (top to bottom) we see that the number of edges decrease, while in graph12, along the z1 axis (left to right), the number of edges increase. 3) The variable z2 controls the number of nodes, and we see that in graph12 and graph02 the number of nodes decreases along the z2 axis (bottom to top). Disentanglement metrics. We perform 10 random seed runs, by training for 200 epochs on the proposed synthetic datasets and measure the quantitative metrics on 1000 data points. In terms of Figure 4: Graph traversals (attributes and node values) for the combinations of 3 latent variables. Table 1: Disentanglement results. Watts-Strogatz Erdos-Renyi Model FVM Beta MIG DCI FL FVM Beta MIG DCI FL GCN 69.6 0.8 66.5 0.7 23.2 2.5 43.8 1.6 84.1 0.5 57.0 4.5 61.0 1.4 22.5 3.3 54.1 2.1 71.7 2.6 GAT 72.6 1.3 66.2 3.4 17.4 1.0 53.2 2.7 79.0 1.1 56.0 3.2 66.3 2.5 31.4 1.9 54.0 2.9 70.2 2.1 FAC 74.2 1.3 65.7 2.6 26.4 2.0 53.4 4.0 80.3 0.9 67.2 1.7 66.3 3.3 35.1 2.4 53.8 1.5 78.1 3.0 DIS 73.0 3.5 69.3 2.1 27.1 1.7 52.2 3.9 85.2 2.0 68.1 1.8 64.1 0.5 41.3 1.4 53.5 2.3 72.4 2.3 SIDU 80.5 1.5 71.6 4.5 28.5 2.8 55.4 2.0 91.0 2.3 83.0 2.9 71.8 3.2 53.2 0.8 58.6 1.9 87.1 4.0 SIDC 81.9 1.2 74.5 3.2 49.1 3.1 59.7 1.2 92.3 0.9 83.3 0.7 74.1 1.2 52.4 3.1 60.5 1.2 89.8 2.3 baselines, we consider graph VAEs with GAT [60] and GCN [29] encoders, as well as disentangled encoders such as FAC [65] and DIS [38]. We set our models to have a group size of 81, a hessian penalty of 40, and a commutative penalty of 5. In Table 1 we observe that our models are able to improve on previous baselines on all metrics on the evaluated datasets, and the conditional version achieves the best performance in most cases. We notice that the FL metric shows a significant performance increase, justified by its ability to capture the disentanglement on each generative factor, which, in our models is controlled by the group size, while in previous approaches is not considered. In terms of the other previously proposed disentangled approaches, DIS and FAC demonstrate higher disentanglement in most cases, when compared to GCN and GAT, however they are outperformed by our methods. 5.2 Compression and few-shots classification Following the setup from Ge et al. [14], we consider the task of learning a compressed model via multiple pooling operations, and test on few-shots classification capabilities on datasets with multiple classes, including FRANKENSTEIN [43] (2 classes), COLORS-3 [30] (11 classes), Mutagenicity [51] (2 classes), NCI1 [53] (2 c). The baselines include MIA [14], which propose an attention-based pooling for compression, as well as GCN [29], and GAT [60] based autoencoders, equipped with the same pooling layer. All models are set to have a pooling rate of 0.8, and a depth of 3 layers. Our models are set with a group size of 81, hessian penalty of 20 and commutative penalty of 5. The task consists in training first without labels to learn the representation, and then using the compressed model as input for training a GCN classifier a labelled subset of the dataset, which involves 100 samples for training and 100 for testing. In Table 2 we report the mean and variance across 10 runs for MSE, the classification accuracy, and the size of the trained model. The results show that SIDC and SIDU outperform the considered baselines in terms of few-shots classification accuracy on all datasets, while achieving a smaller compressed size. We hypothesize that the superior accuracy performance of our models is due to a more efficient learning provided by disentangled representations, which have previously demonstrated the ability to enhance the accuracy of predictions in the context of generalization tasks [41, 69, 32]. In terms of MSE, our models show an improvement compared to GCNand GAT-based autoencoders, but they are outperformed by MIA in most cases. Table 2: Compression and few shot classification results. FRANKENSTEIN COLORS-3 Mutagenicity NCI1 Model MSE Size Acc. MSE Size Acc. MSE Size Acc. MSE Size Acc. MIA 1.6 0.5 4.9M 65 1 1.8 0.2 729K 33 2 4.1 0.8 753K 78 2 3.2 0.5 777K 61 1 GCN 12.6 2.5 4.2M 39 3 11.2 1.1 657K 33 2 16.5 2.1 673K 72 1 7.4 1.2 697K 53 4 GAT 9.0 1.2 4.2M 26 2 10.1 3.1 665K 30 1 11.3 2.8 681K 79 4 8.1 0.3 705K 50 2 SIDU 4.3 1.1 4.1M 68 2 5.1 1.5 625K 39 1 4.2 0.3 633K 81 3 3.5 0.3 657K 63 2 SIDC 2.8 0.5 4.1M 69 2 1.9 0.4 625K 38 3 3.2 1.1 633K 84 2 3.9 0.9 657K 66 2 Table 3: Random graph generation. ZINC QM9 MOSES Model Val WR Uni Nov Val WR Uni Nov Val WR Uni Nov JT-VAE 100 n/a 100 100 n/a n/a n/a n/a 100 n/a 99.96 91.43 GCPN 100 20 99.97 100 n/a n/a n/a n/a n/a n/a n/a n/a Graph AF 100 68 99.1 100 100 67 94.15 88.83 100 71 99.99 100 Graph DF 100 89.03 99.16 100 100 82.67 97.62 98.1 100 87.58 99.55 100 SIDU 100 78.21 99.12 100 100 75.43 95.22 90.33 100 81.62 99.62 100 SIDC 100 86.02 99.14 100 100 82.92 96.43 92.28 100 84.29 99.79 100 5.3 Molecular graph generation Molecular generation involves three tasks, random generation, property optimization and constrained optimization, and a suitable setup can be obtained following the approaches implemented via Torch Drug2 and DIG [33]. The generation process involves 1) learning the distribution of the molecular data and 2) fine-tuning the pre-trained model on one of the tasks. We employ our models during the training phase, using a group size of 81, a hessian penalty of 40 and commutative penalty of 5, and then we follow the reinforcement learning fine-tuning method from GCPN [66]. Similar setups are used from previous molecule generation methods, which we include as baselines: JT-VAE [24], Graph AF [54], Graph DF [37], GCPN [66]. Random generation. This task evaluates the quality of randomly generated samples on 4 standard metrics in percentage, including: valid molecules with resampling (Val), valid molecules without resampling (WR), unique molecules (Uni), novel molecules that not appear in the training data (Nov). We train our models for 10 epochs, with a batch size of 32 and the learning rate of 0.001, and compute the metrics over 10K generated molecules. In Table 3 we report results on ZINC [23], QM9 [49], and MOSES [47]. We observe that both SIDU and SIDC are able to improve the performance of Graph AF and GCPN on most metrics, while achieving comparable performance with Graph DF, furthermore the SIDC model achieves the highest score of validity without resampling on the QM9 dataset. Since our model is not optimized for molecule generation, the positive results of our models indicate that disentangled representations may represent a flexible tool for generating more realistic graphs, and that encouraging the separation of semantic factors into different latent codes, may be beneficial for improving the quality of the samples. Property optimization The goal of the task is to generate novel molecules with high property scores for the penalized log P property, and the quantitative estimation of drug-likeness property (QED). The setup involves pretraining our models for 300 epochs on ZINC random generation, applying the RL fine-tuning procedure from GCPN, and measuring the scores from the top 3 generated molecules. In Table 4 we observe that our models are able to outperform GCPN and Graph AF for both penalized log P and QED, and achieve comparable performance to the more advanced Graph DF model. In Figure 5 we show the molecules generated using SIDC. While our model does not outperform Graph DF, our results are relevant because they demonstrate that the disentangled representations learned from our models can be leveraged to improve the performance of the downstream task of property optimization. 2https://torchdrug.ai/ (Apache license) Table 4: Property optimization performance. Penalized log P QED 1st 2nd 3rd 1st 2nd 3rd ZINC 4.52 4.3 4.23 0.948 0.948 0.948 JT-VAE 5.3 4.93 4.49 0.925 0.911 0.910 GCPN 7.98 7.85 7.80 0.948 0.947 0.946 Graph AF 12.23 11.29 11.05 0.948 0.948 0.947 Graph DF 13.7 13.18 13.17 0.948 0.948 0.948 SIDU 12.56 12.46 12.03 0.947 0.948 0.947 SIDC 12.89 12.82 12.27 0.948 0.948 0.948 Figure 5: Molecules from SIDC Table 5: Constrained optimization performance on 800 molecules used in Graph AF. δ Graph AF Graph DF SIDC Imp Sim Suc Imp Sim Suc Imp Sim Suc 0.0 13.13 6.89 0.29 0.15 100 14.15 6.86 0.29 0.13 100 13.26 3.24 0.28 0.21 100 0.2 11.90 6.86 0.33 0.12 100 12.77 6.59 0.32 0.11 100 12.35 5.62 0.32 0.13 100 0.4 8.21 6.51 0.49 0.09 99.8 9.19 6.43 0.48 0.08 99.6 8.25 4.93 0.50 0.18 98.4 0.6 4.98 6.49 0.66 0.05 96.8 4.51 5.80 0.65 0.05 92.1 4.67 5.39 0.66 0.03 93.2 Constrained Optimization. This task aims to modify the input molecular graph for improving its penalized log P score while keeping the similarity between the input and modified molecules higher than the threshold δ. We follow the setup of Graph AF and Graph DF, which select 800 molecules from ZINC with low penalized log P scores as the input molecules to be optimized. We pretrain our model on the random generation task for 300 epochs, and then fine-tune with the RL procedure from Graph AF. We report the mean and standard deviation of the largest property improvement (Imp), and similarities (Sim) between them and their corresponding input molecules, as well as the success rate (Suc). In Table 5 we compare the results for our SIDC model with Graph AF and Graph DF. We observe that SIDC is able to outperform Graph AF 3 out of 4 times for improvement values, and achieves comparable results with Graph DF, which we motivate by the fact that Graph DF provides further fine-tuning in order to improve the baseline. In terms of similarity and success rate, our model has comparable results with the baselines for all δ setups. 6 Discussion Limitations. For quantitative evaluation, we rely on synthetic data, since current metrics are based on the ability to sample the factors and combine them into observations Kim and Mnih [26]. Future work should investigate how to provide metrics that can evaluate disentanglement on real-world datasets. A recent line of work from Khemakhem et al. [25] shows that disentanglement is closely related to model identifiability, i.e., a representation is disentangled when a set of learned parameters is uniquely identified with the parameters in the true distribution. Our approach has not considered or provided proofs for, identifiability, and we leave this as future work. Conclusion. We formalize the notion of conditional disentanglement on graphs and propose a novel framework for graph disentanglement by leveraging tools from Lie algebras. Based on the new definition of disentanglement, we design a graph VAE based on a Lie group parameterization, and provide a novel ELBO criteria for optimizing conditional disentanglement. Our method achieves superior performance on quantitative disentanglement benchmarks when compared to contemporary disentangled GNNs and other convolutional layers. Finally, we demonstrate strong capabilities on few-shots classification and molecular generation experiments. 7 Acknowledgements We thank the anonymous reviewers for their helpful comments. GM s research was partially funded by EPSRC and the BBC under i CASE. [1] Inhwan Bae and Hae-Gon Jeon. Disentangled multi-relational graph convolutional network for pedestrian trajectory prediction. In Proceedings of the AAAI Conference on Artificial Intelligence, volume 35, pages 911 919, 2021. [2] Yoshua Bengio, Aaron Courville, and Pascal Vincent. Representation learning: A review and new perspectives. IEEE transactions on pattern analysis and machine intelligence, 35(8): 1798 1828, 2013. [3] Beatrice Bevilacqua, Fabrizio Frasca, Derek Lim, Balasubramaniam Srinivasan, Chen Cai, Gopinath Balamurugan, Michael M. Bronstein, and Haggai Maron. Equivariant subgraph aggregation networks. In International Conference on Learning Representations, 2022. [4] Diane Bouchacourt, Mark Ibrahim, and Stéphane Deny. Addressing the topological defects of disentanglement via distributed operators. ar Xiv preprint ar Xiv:2102.05623, 2021. [5] Michael M Bronstein, Joan Bruna, Yann Le Cun, Arthur Szlam, and Pierre Vandergheynst. Geometric deep learning: going beyond euclidean data. IEEE Signal Processing Magazine, 34 (4):18 42, 2017. [6] Hugo Caselles-Dupré, Michael Garcia Ortiz, and David Filliat. Symmetry-based disentangled representation learning requires interaction with environments. Advances in Neural Information Processing Systems, 32, 2019. [7] Ricky TQ Chen, Xuechen Li, Roger Grosse, and David Duvenaud. Isolating sources of disentanglement in vaes. In Proceedings of the 32nd International Conference on Neural Information Processing Systems, pages 2615 2625, 2018. [8] Zhengdao Chen, Soledad Villar, Lei Chen, and Joan Bruna. On the equivalence between graph isomorphism testing and function approximation with gnns. In Neur IPS, 2019. [9] Kien Do and Truyen Tran. Theory and evaluation metrics for learning disentangled representations. In International Conference on Learning Representations, 2019. [10] Yuanqi Du, Xiaojie Guo, Hengning Cao, Yanfang Ye, and Liang Zhao. Disentangled spatiotemporal graph generative models. In Proceedings of the AAAI Conference on Artificial Intelligence, 2022. [11] Cian Eastwood and Christopher KI Williams. A framework for the quantitative evaluation of disentangled representations. In International Conference on Learning Representations, 2018. [12] Marco Fumero, Luca Cosmo, Simone Melzi, and Emanuele Rodolà. Learning disentangled representations via product manifold projection. In International Conference on Machine Learning, pages 3530 3540. PMLR, 2021. [13] V. Garg, S. Jegelka, and T. Jaakkola. Generalization and representational limits of graph neural networks. In International Conference on Machine Learning (ICML), 2020. [14] Yunhao Ge, Yunkui Pang, Linwei Li, and Laurent Itti. Graph autoencoder for graph compression and representation learning. In Neural Compression: From Information Theory to Applications Workshop@ ICLR 2021, 2021. [15] M. Gori, G. Monfardini, and F. Scarselli. A new model for learning in graph domains. In IEEE International Joint Conference on Neural Networks (IJCNN), 2005. [16] Jingwei Guo, Kaizhu Huang, Xinping Yi, and Rui Zhang. Lgd-gcn: Local and global disentangled graph convolutional networks. ar Xiv preprint ar Xiv:2104.11893, 2021. [17] Xiaojie Guo, Liang Zhao, Zhao Qin, Lingfei Wu, Amarda Shehu, and Yanfang Ye. Interpretable deep graph generation with node-edge co-disentanglement. In Proceedings of the 26th ACM SIGKDD international conference on knowledge discovery & data mining, pages 1697 1707, 2020. [18] Xiaojie Guo, Yuanqi Du, and Liang Zhao. Deep generative models for spatial networks. In Proceedings of the 27th ACM SIGKDD Conference on Knowledge Discovery & Data Mining, pages 505 515, 2021. [19] Irina Higgins, Loic Matthey, Arka Pal, Christopher Burgess, Xavier Glorot, Matthew Botvinick, Shakir Mohamed, and Alexander Lerchner. beta-vae: Learning basic visual concepts with a constrained variational framework. In International Conference on Learning Representations, 2017. [20] Irina Higgins, David Amos, David Pfau, Sebastien Racaniere, Loic Matthey, Danilo Rezende, and Alexander Lerchner. Towards a definition of disentangled representations. ar Xiv preprint ar Xiv:1812.02230, 2018. [21] Irina Higgins, Nicolas Sonnerat, Loic Matthey, Arka Pal, Christopher P Burgess, Matko Bošnjak, Murray Shanahan, Matthew Botvinick, Demis Hassabis, and Alexander Lerchner. Scan: Learning hierarchical compositional visual concepts. In International Conference on Learning Representations, 2018. [22] Irina Higgins, Sébastien Racanière, and Danilo Rezende. Symmetry-based representations for artificial and biological general intelligence. Frontiers in Computational Neuroscience, page 28, 2022. [23] John J Irwin, Teague Sterling, Michael M Mysinger, Erin S Bolstad, and Ryan G Coleman. Zinc: a free tool to discover chemistry for biology. Journal of chemical information and modeling, 52 (7):1757 1768, 2012. [24] Wengong Jin, Regina Barzilay, and Tommi Jaakkola. Junction tree variational autoencoder for molecular graph generation. In International conference on machine learning, pages 2323 2332. PMLR, 2018. [25] Ilyes Khemakhem, Diederik Kingma, Ricardo Monti, and Aapo Hyvarinen. Variational autoencoders and nonlinear ica: A unifying framework. In International Conference on Artificial Intelligence and Statistics, pages 2207 2217. PMLR, 2020. [26] Hyunjik Kim and Andriy Mnih. Disentangling by factorising. In International Conference on Machine Learning, pages 2649 2658, 2018. [27] Diederik P Kingma and Max Welling. Auto-encoding variational bayes. In 2nd International Conference on Learning Representations, ICLR 2014, Banff, AB, Canada, April 14-16, 2014, Conference Track Proceedings, 2014. [28] Thomas N Kipf and Max Welling. Variational graph auto-encoders. ar Xiv preprint ar Xiv:1611.07308, 2016. [29] Thomas N. Kipf and Max Welling. Semi-supervised classification with graph convolutional networks. In International Conference on Learning Representations (ICLR), 2017. [30] Boris Knyazev, Graham W Taylor, and Mohamed Amer. Understanding attention and generalization in graph neural networks. Advances in neural information processing systems, 32, 2019. [31] Haoyang Li, Xin Wang, Ziwei Zhang, Zehuan Yuan, Hang Li, and Wenwu Zhu. Disentangled contrastive learning on graphs. Advances in Neural Information Processing Systems, 34, 2021. [32] Xiangyu Li, Zhe Xu, Kun Wei, and Cheng Deng. Generalized zero-shot learning via disentangled representation. In Proceedings of the AAAI Conference on Artificial Intelligence, volume 35, pages 1966 1974, 2021. [33] Meng Liu, Youzhi Luo, Limei Wang, Yaochen Xie, Hao Yuan, Shurui Gui, Haiyang Yu, Zhao Xu, Jingtun Zhang, Yi Liu, et al. Dig: a turnkey library for diving into graph deep learning research. Journal of Machine Learning Research, 22(240):1 9, 2021. [34] Qi Liu, Miltiadis Allamanis, Marc Brockschmidt, and Alexander Gaunt. Constrained graph variational autoencoders for molecule design. Advances in neural information processing systems, 31, 2018. [35] Yanbei Liu, Xiao Wang, Shu Wu, and Zhitao Xiao. Independence promoted graph disentangled networks. In Proceedings of the AAAI Conference on Artificial Intelligence, volume 34, pages 4916 4923, 2020. [36] Francesco Locatello, Stefan Bauer, Mario Lucic, Gunnar Raetsch, Sylvain Gelly, Bernhard Schölkopf, and Olivier Bachem. Challenging common assumptions in the unsupervised learning of disentangled representations. In international conference on machine learning, pages 4114 4124. PMLR, 2019. [37] Youzhi Luo, Keqiang Yan, and Shuiwang Ji. Graphdf: A discrete flow model for molecular graph generation. In International Conference on Machine Learning, pages 7192 7203. PMLR, 2021. [38] Jianxin Ma, Peng Cui, Kun Kuang, Xin Wang, and Wenwu Zhu. Disentangled graph convolutional networks. In International conference on machine learning, pages 4212 4221. PMLR, 2019. [39] Haggai Maron, Heli Ben-Hamu, Hadar Serviansky, and Yaron Lipman. Provably powerful graph networks. Advances in Neural Information Processing Systems, 32:2156 2167, 2019. [40] Graziano Mita, Maurizio Filippone, and Pietro Michiardi. An identifiable double vae for disentangled representations. In International Conference on Machine Learning, pages 7769 7779. PMLR, 2021. [41] Milton Llera Montero, Casimir JH Ludwig, Rui Ponte Costa, Gaurav Malhotra, and Jeffrey Bowers. The role of disentanglement in generalisation. In International Conference on Learning Representations, 2020. [42] Milton Llera Montero, Casimir JH Ludwig, Rui Ponte Costa, Gaurav Malhotra, and Jeffrey Bowers. The role of disentanglement in generalisation. In International Conference on Learning Representations, 2021. URL https://openreview.net/forum?id=qb H974j KUVy. [43] Francesco Orsini, Paolo Frasconi, and Luc De Raedt. Graph invariant kernels. In Twenty-Fourth International Joint Conference on Artificial Intelligence, 2015. [44] Matthew Painter, Adam Prugel-Bennett, and Jonathon Hare. Linear disentangled representations and unsupervised action estimation. Advances in Neural Information Processing Systems, 33: 13297 13307, 2020. [45] William Peebles, John Peebles, Jun-Yan Zhu, Alexei Efros, and Antonio Torralba. The hessian penalty: A weak prior for unsupervised disentanglement. In European Conference on Computer Vision, pages 581 597. Springer, 2020. [46] David Pfau, Irina Higgins, Alex Botev, and Sébastien Racanière. Disentangling by subspace diffusion. Advances in Neural Information Processing Systems, 33:17403 17415, 2020. [47] Daniil Polykovskiy, Alexander Zhebrak, Benjamin Sanchez-Lengeling, Sergey Golovanov, Oktai Tatanov, Stanislav Belyaev, Rauf Kurbanov, Aleksey Artamonov, Vladimir Aladinskiy, Mark Veselov, et al. Molecular sets (moses): a benchmarking platform for molecular generation models. Frontiers in pharmacology, 11:1931, 2020. [48] Robin Quessard, Thomas Barrett, and William Clements. Learning disentangled representations and group structure of dynamical environments. Advances in Neural Information Processing Systems, 33:19727 19737, 2020. [49] Raghunathan Ramakrishnan, Pavlo O Dral, Matthias Rupp, and O Anatole Von Lilienfeld. Quantum chemistry structures and properties of 134 kilo molecules. Scientific data, 1(1):1 7, 2014. [50] Danilo Jimenez Rezende, Shakir Mohamed, and Daan Wierstra. Stochastic backpropagation and approximate inference in deep generative models. In International conference on machine learning, pages 1278 1286. PMLR, 2014. [51] Kaspar Riesen and Horst Bunke. Iam graph database repository for graph based pattern recognition and machine learning. In Joint IAPR International Workshops on Statistical Techniques in Pattern Recognition (SPR) and Structural and Syntactic Pattern Recognition (SSPR), pages 287 297. Springer, 2008. [52] Wulf Rossmann. Lie groups: an introduction through linear groups, volume 5. Oxford University Press on Demand, 2006. [53] Nino Shervashidze, Pascal Schweitzer, Erik Jan Van Leeuwen, Kurt Mehlhorn, and Karsten M Borgwardt. Weisfeiler-lehman graph kernels. Journal of Machine Learning Research, 12(9), 2011. [54] Chence Shi, Minkai Xu, Zhaocheng Zhu, Weinan Zhang, Ming Zhang, and Jian Tang. Graphaf: a flow-based autoregressive model for molecular graph generation. In International Conference on Learning Representations, 2020. [55] Martin Simonovsky and Nikos Komodakis. Graphvae: Towards generation of small graphs using variational autoencoders. In International conference on artificial neural networks, pages 412 422. Springer, 2018. [56] Niklas Stoehr, Emine Yilmaz, Marc Brockschmidt, and Jan Stuehmer. Disentangling interpretable generative parameters of random and real-world graphs. ar Xiv preprint ar Xiv:1910.05639, 2019. [57] Loek Tonnaer, Luis Armando Perez Rey, Vlado Menkovski, Mike Holenderski, and Jim Portegies. Quantifying and learning linear symmetry-based disentanglement. In Proceedings of the 39th International Conference on Machine Learning, volume 162 of Proceedings of Machine Learning Research, pages 21584 21608, 17 23 Jul 2022. [58] Michael Tschannen, Olivier Bachem, and Mario Lucic. Recent advances in autoencoder-based representation learning. ar Xiv preprint ar Xiv:1812.05069, 2018. [59] Sjoerd Van Steenkiste, Francesco Locatello, Jürgen Schmidhuber, and Olivier Bachem. Are disentangled representations helpful for abstract visual reasoning? Advances in Neural Information Processing Systems, 32, 2019. [60] Petar Veliˇckovi c, Guillem Cucurull, Arantxa Casanova, Adriana Romero, Pietro Liò, and Yoshua Bengio. Graph attention networks. In International Conference on Learning Representations, 2018. [61] Tan Wang, Zhongqi Yue, Jianqiang Huang, Qianru Sun, and Hanwang Zhang. Self-supervised learning disentangled group representation as feature. Advances in Neural Information Processing Systems, 34, 2021. [62] Tailin Wu, Hongyu Ren, Pan Li, and Jure Leskovec. Graph information bottleneck. Advances in Neural Information Processing Systems, 33:20437 20448, 2020. [63] K. Xu, W. Hu, J. Leskovec, and S. Jegelka. How powerful are graph neural networks? In International Conference on Learning Representations (ICLR), 2019. [64] Tao Yang, Xuanchi Ren, Yuwang Wang, Wenjun Zeng, and Nanning Zheng. Towards building a group-based unsupervised representation disentanglement framework. In International Conference on Learning Representations, 2022. [65] Yiding Yang, Zunlei Feng, Mingli Song, and Xinchao Wang. Factorizable graph convolutional networks. Advances in Neural Information Processing Systems, 33:20286 20296, 2020. [66] Jiaxuan You, Bowen Liu, Zhitao Ying, Vijay Pande, and Jure Leskovec. Graph convolutional policy network for goal-directed molecular graph generation. Advances in neural information processing systems, 31, 2018. [67] Jiaxuan You, Rex Ying, Xiang Ren, William Hamilton, and Jure Leskovec. Graphrnn: Generating realistic graphs with deep auto-regressive models. In International conference on machine learning, pages 5708 5717. PMLR, 2018. [68] Junchi Yu, Tingyang Xu, Yu Rong, Yatao Bian, Junzhou Huang, and Ran He. Graph information bottleneck for subgraph recognition. In International Conference on Learning Representations, 2021. URL https://openreview.net/forum?id=b M4Iqfg8M2k. [69] Hanlin Zhang, Yi-Fan Zhang, Weiyang Liu, Adrian Weller, Bernhard Schölkopf, and Eric P Xing. Towards principled disentanglement for domain generalization. ar Xiv preprint ar Xiv:2111.13839, 2021. [70] Xinqi Zhu, Chang Xu, and Dacheng Tao. Commutative lie group vae for disentanglement learning. In International Conference on Machine Learning, pages 12924 12934. PMLR, 2021. 1. For all authors... (a) Do the main claims made in the abstract and introduction accurately reflect the paper s contributions and scope? 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