Path analysis calculates how correlation arises from specified paths in a causal graph, separating direct and indirect effects across confounder, mediator, and collider structures. section 6.2.2
A practical analysis asks how graph structure changes observed and adjusted relationships:
- Compare the correlation between X and Y with regression coefficients from Y ~ X and Y ~ X + Z. section 6.2.2
- Use variance, covariance, correlation, and linear-regression equations to calculate how association propagates through arrows. section 6.2.2
- Check whether conditioning changes correlation differently for confounders, mediators, and colliders. section 6.2.2
Table 6.12 Differences between causal paths (dashed lines) and correlation propagation (double-headed arrows)
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Case
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Causal paths
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Correlation propagation
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Confounder
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Mediator
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Collider
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Compare causal paths with correlation propagation across confounder, mediator, and collider graphs. section 6.2.2
