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The presence of interference, where the outcome of an individual may depend on the treatment assignment and behavior of neighboring nodes, can lead to biased causal effect estimation. Current approaches to network experiment design focus on limiting interference through cluster-based randomization, in which clusters are identified using graph clustering, and cluster randomization dictates the node assignment to treatment and control. However, cluster-based randomization approaches perform poorly when interference propagates in cascades, whereby the response of individuals to treatment propagates to their multi-hop neighbors. When we have knowledge of the cascade seed nodes, we can leverage this interference structure to mitigate the resulting causal effect estimation bias. With this goal, we propose a cascade-based network experiment design that initiates treatment assignment from the cascade seed node and propagates the assignment to their multi-hop neighbors to limit interference during cascade growth and thereby reduce the overall causal effect estimation error. Our extensive experiments on real-world and synthetic datasets demonstrate that our proposed framework outperforms the existing state-of-the-art approaches in estimating causal effects in network data.
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Coupling erosion, weathering, and hydrologic function in an active orogenic system
This multi-disciplinary project is a collaboration of USA, Nepal, and U.K. scientists to investigate the multi-scale relationships between tectonic uplift, topographic evolution, chemical weathering, and seismicity. The Himalayan orogen in central Nepal is the representative study site. The seismic experiment is a set of high resolution dense arrays to image the near surface to hundreds of meters depth. The experiment used 309 three-component 5-Hz nodes at nominal 100 m spacing, deployed and recorded for one month. 21 of these nodes were arranged in a local 2D array. Circle array collection was also carried out targeting shallow fracture anisotropy.
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- PAR ID:
- 10565083
- Publisher / Repository:
- International Federation of Digital Seismograph Networks
- Date Published:
- Format(s):
- Medium: X Size: 4200000 MB Other: SEED data
- Size(s):
- 4200000 MB
- Location:
- (East Bound Longitude:86.000; North Bound Latitude:28.500; South Bound Latitude:27.500; West Bound Longitude:85.000)
- Sponsoring Org:
- National Science Foundation
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