CAETC: Causal Autoencoding and Treatment Conditioning for Counterfactual Estimation over Time
Organizations: Siebel School of Computing and Data Science, University of Illinois Urbana-Champaign · VinUni-Illinois Smart Health Center, VinUniversity · AI Innovation Institute, Stony Brook University · Department of Electrical and Computer Engineering, University of Illinois Urbana-Champaign
Abstract
Counterfactual estimation over time is important in various applications, such as personalized medicine. However, time-dependent confounding bias in observational data still poses a significant challenge in achieving accurate and efficient estimation. We introduce causal autoencoding and treatment conditioning (CAETC), a novel method for this problem. Built on adversarial representation learning, our method leverages an autoencoding architecture to learn a partially invertible and treatment-invariant representation, where the outcome prediction task is cast as applying a treatment-specific conditioning on the representation. Our design is independent of the underlying sequence model and can be applied to existing architectures such as long short-term memories (LSTMs) or temporal convolution networks (TCNs). We conduct extensive experiments on synthetic, semi-synthetic, and real-world data to demonstrate that CAETC yields significant improvement in counterfactual estimation over existing methods.
Figures & tables
| Avg | |||||||||||
| LSTM | .363 .028 | .417 .025 | .463 .021 | .506 .020 | .546 .017 | .581 .016 | .615 .016 | .649 .015 | .682 .016 | .715 .017 | .554 |
| RMSN | .408 .029 | .471 .032 | .530 .030 | .587 .030 | .641 .030 | .690 .030 | .737 .028 | .782 .025 | .825 .022 | .867 .023 | .654 |
| CRN | .365 .028 | .424 .027 | .476 .023 | .524 .021 | .569 .019 | .608 .018 | .647 .018 | .685 .018 | .723 .020 | .760 .022 | .578 |
| CT | .324 .017 | .411 .024 | .499 .035 | .582 .040 | .660 .041 | .733 .043 | .808 .046 | .882 .046 | .941 .048 | .999 .053 | .684 |
| CAETC LSTM | .330 .021 | .393 .019 | .442 .014 | .487 .009 | .528 .006 | .564 .007 | .600 .011 | .634 .014 | .668 .017 | .702 .020 | .535 |
| CAETC TCN | .322 .016 | .391 .019 | .447 .023 | .495 .027 | .540 .029 | .582 .030 | .621 .032 | .657 .032 | .692 .032 | .726 .032 | .547 |
| Avg | ||||||
| LSTM | 6.80 0.02 | 7.32 0.05 | 7.61 0.05 | 7.82 0.05 | 7.99 0.07 | 7.51 |
| RMSN | 7.29 0.07 | 7.80 0.07 | 8.10 0.10 | 8.33 0.16 | 8.54 0.21 | 8.01 |
| CRN | 6.81 0.04 | 7.35 0.05 | 7.64 0.06 | 7.86 0.07 | 8.04 0.10 | 7.54 |
| CT | 6.70 0.04 | 7.37 0.06 | 7.71 0.07 | 7.93 0.07 | 8.10 0.04 | 7.56 |
| CAETC LSTM | 6.72 0.05 | 7.27 0.05 | 7.56 0.06 | 7.76 0.06 | 7.91 0.08 | 7.45 |
| CAETC TCN | 6.69 0.06 | 7.24 0.05 | 7.53 0.04 | 7.72 0.03 | 7.88 0.06 | 7.41 |
| CAETC LSTM | Avg | |||||
| Full | 7.74 0.57 | 9.01 0.84 | 9.28 0.78 | 9.09 0.8 | 8.42 0.72 | 8.71 |
| 7.75 0.57 | 9.09 0.86 | 9.45 0.87 | 9.37 0.98 | 8.79 1.04 | 8.89 | |
| 8.01 0.91 | 9.58 1.31 | 10.06 1.44 | 10.05 1.61 | 9.45 1.49 | 9.43 |
Appendix figures & tables9 assets
Supplementary material from the paper’s appendix.
Appendix
| Time-varying covariates |
| heart rate |
| red blood cell count |
| sodium |
| mean blood pressure |
| systemic vascular resistance |
| glucose |
| Input : or |
| LSTM (# layers) |
| Linear Layer |
| ELU Activation |
| Output : or |
| Input : |
| LSTM (# layers) |
| Linear Layer |
| ELU Activation |
| Output : |
| Input : |
| 3x Transformers (# layers) |
| Output : |
| Method | Components | Hyperparameters | NSCLC range | MIMIC III range (semi-synthetic & real) |
| LSTM & CRN | Encoder & Decoder | # layers | 1 | 1,2 |
| # hidden units | 16, 32, 48 | 32, 48, 64 | ||
| Dropout rate | 0.0, 0.1 | |||
| Encoder | # epochs | 100 | 150 | |
| Learning rate | 0.001, 0.0001 | |||
| Batch size | 64, 128 | |||
Causal Effect Estimation
Causal effect estimation measures how outcomes would change under interventions, using experiments or observational data and explicit assumptions.
See all 264 papers