π€ AI Summary
This study addresses the problem of model-free recovery of latent influence networks from observed cascade data. To this end, the authors propose CascadeNet, a framework that characterizes influence structures by nonparametrically estimating the Jacobian matrix of the one-step transition function and constructs a Neyman-orthogonal debiased estimator via the Riesz representation theorem, enabling βn-consistent and asymptotically normal inference for network edges. The method makes no assumptions about the underlying diffusion mechanism and achieves state-of-the-art accuracy in network recovery across nine simulation scenarios. In an empirical application to COVID-19 transmission across Spainβs 52 provinces, the inferred network exhibits strong alignment with actual human mobility patterns and significantly outperforms existing baselines.
π Abstract
Many important outcomes unfold as dynamic cascades, including product adoption, disease spread, financial distress, and information diffusion. A central challenge is to recover the hidden influence network behind these cascades. Existing methods typically assume a specific diffusion model, and their performance degrades substantially when that assumption is misspecified. We propose CascadeNet, a Jacobian-based machine learning framework for network recovery that does not require specifying a diffusion mechanism. The key idea is that the underlying influence structure can be characterized by the Jacobian of the one-step transition function. CascadeNet first constructs a flexible estimator of the transition function, and further applies Neyman-orthogonal debiasing via the Riesz representer, so that the debiased Jacobian is $\sqrt{n}$-consistent and asymptotically normal, enabling formal inference on the network structure. We validate CascadeNet in both a simulation exercise and a real-world empirical application. In simulations, where the data-generating process is known, CascadeNet achieves the highest network recovery accuracy across nine common data-generating processes. In an empirical application to COVID-19 transmission across Spain's 52 provinces, CascadeNet recovers transmission networks that are significantly correlated with the true inter-province mobility network, whereas networks recovered by baseline methods show no significant alignment with the ground truth.