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Published on: January 7, 2019
Why your DAG should probably incorporate sampling and measurement processes
Robin J Boyd1, Rob Cooke1, Gary D Powney2
1UK Centre for Ecology and Hydrology, Benson Lane, Crowmarsh Gifford, OX108BB, UK; Centre for Ecology and Conservation, University of Exeter, Falmouth, Cornwall, UK.
Insect scientists can enhance causal inference by incorporating sampling and measurement assumptions into Directed Acyclic Graphs (DAGs). This approach provides a comprehensive framework for understanding observed associations, regardless of the research question.
Area of Science:
- Ecology
- Entomology
- Causal Inference
Background:
- Directed Acyclic Graphs (DAGs) are increasingly used by insect scientists to visualize pre-data causal assumptions.
- Current DAG applications often overlook the crucial role of observation processes (sampling and measurement) in interpreting associations.
- This oversight can limit the ability to draw robust causal conclusions from observed data.
Purpose of the Study:
- To explain how insect scientists can integrate assumptions about sampling and measurement into DAGs.
- To demonstrate that DAGs can serve as a general framework for displaying assumptions for various inferential goals.
- To highlight the necessity of explicit sampling and measurement assumptions for holistic causal reasoning.
Main Methods:
- Drawing on interdisciplinary literature to inform the application of DAGs in entomology.
- Developing a conceptual framework for incorporating observation process assumptions within DAGs.
- Illustrating how explicit assumptions facilitate causal interpretation of observed associations.
Main Results:
- Observed associations in insect science are contingent upon both causal structure and observation process assumptions.
- Explicitly including sampling and measurement assumptions in DAGs enhances the rigor of causal inference.
- DAGs incorporating observation processes are valuable for descriptive and predictive questions, not solely causal inference.
Conclusions:
- DAGs offer a powerful, generalizable framework for visualizing and reasoning about scientific assumptions in entomology.
- Integrating sampling and measurement assumptions into DAGs is essential for robust causal interpretation and broader inferential goals.
- This expanded use of DAGs promotes more comprehensive and transparent scientific reasoning in insect science.
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