Point Process

Where should you model timing?

Where you model timing effect Training and Prediction Steps

Marked VS Multi-dim TPP

They are targeting “multi” on type of interaction, Node respectively: Marked: Multi- types of interaction (usually represent as $k$) MTPP: Multi- number of Node One easy way to differntiate them is by the likelihood function:

MTPP via Graph used for NRI

Zhang, Yunhao, and Junchi Yan. 2021. “Neural Relation Inference for Multi-Dimensional Temporal Point Processes via Message Passing Graph.” In , 3:3406–12. https://doi.org/10.24963/ijcai.2021/469. A multidimentional(D nodes) marked(M types of possible events) TPP($N_m$ length of sequence) modeling

Active TPP Researcher

Researcher Junchi Yan Graph with MTPP explicit graph structures Shang and Sun, 2019 Wu et al., 2020 Liu et al., 2018 use MTPP to model topological evolution of dynamic graphs

Neural Temporal Point Process, A Review

Shchur, Oleksandr, Ali Caner Türkmen, Tim Januschowski, and Stephan Günnemann. 2021. “Neural Temporal Point Processes: A Review.” ArXiv:2104.03528 [Cs], August. http://arxiv.org/abs/2104.03528. Neural TPP = TPP + Deep Learning Model Sequence Events: any sequential model(RNN, transfomer) + TPP

Recurrent Marked Temporal Point Process

The timing modeling is not embedded in the complex structure of RNN, so the pdf of $t$ could be solved analytically

Neural Hawkes Process

Modeling of timing is embedded into the LSTM structure. so the hidden state $h(t)$ is a function of $t$(continuous)

TPP intro: Hawkes Process

Hawkes Process is a special kind of point process with 1. postive 2. additive 3. exponentail decay self-exiciting factor 2.

TPP intro: PDF, CDF, Notations and Likelihood

Point Process is widely used in modeling sequence of events that: 1. timing is important 2.rare to happen