endogenous variable
Intervention and Conditioning in Causal Bayesian Networks
Causal models are crucial for understanding complex systems and identifying causal relationships among variables. Even though causal models are extremely popular, conditional probability calculation of formulas involving interventions pose significant challenges. In case of Causal Bayesian Networks (CBNs), Pearl assumes autonomy of mechanisms that determine interventions to calculate a range of probabilities. We show that by making simple yet often realistic independence assumptions, it is possible to uniquely estimate the probability of an interventional formula (including the well-studied notions of probability of sufficiency and necessity). We discuss when these assumptions are appropriate. Importantly, in many cases of interest, when the assumptions are appropriate, these probability estimates can be evaluated using observational data, which carries immense significance in scenarios where conducting experiments is impractical or unfeasible.
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- North America > United States > Massachusetts (0.04)
- North America > United States > California > San Francisco County > San Francisco (0.04)
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- North America > Canada > Quebec > Montreal (0.05)
- Europe > United Kingdom > England > Cambridgeshire > Cambridge (0.05)
- Asia > China > Beijing > Beijing (0.05)
- North America > United States > California > Orange County > Irvine (0.14)
- Europe > United Kingdom > England > Cambridgeshire > Cambridge (0.04)
- North America > United States > Montana (0.04)
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- Health & Medicine > Therapeutic Area > Oncology (1.00)
- Health & Medicine > Pharmaceuticals & Biotechnology (1.00)
- North America > United States > California > Orange County > Irvine (0.14)
- Europe > United Kingdom > England > Cambridgeshire > Cambridge (0.04)
- North America > United States > Montana (0.04)
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- Health & Medicine > Therapeutic Area > Oncology (1.00)
- Health & Medicine > Pharmaceuticals & Biotechnology (1.00)
- North America > United States > California > Santa Clara County > Palo Alto (0.04)
- North America > Greenland (0.04)
Causality Without Causal Models
Halpern, Joseph Y., Pass, Rafael
Perhaps the most prominent current definition of (actual) causality is due to Halpern and Pearl. It is defined using causal models (also known as structural equations models). We abstract the definition, extracting its key features, so that it can be applied to any other model where counterfactuals are defined. By abstracting the definition, we gain a number of benefits. Not only can we apply the definition in a wider range of models, including ones that allow, for example, backtracking, but we can apply the definition to determine if A is a cause of B even if A and B are formulas involving disjunctions, negations, beliefs, and nested counterfactuals (none of which can be handled by the Halpern-Pearl definition). Moreover, we can extend the ideas to getting an abstract definition of explanation that can be applied beyond causal models. Finally, we gain a deeper understanding of features of the definition even in causal models.
- Europe > United Kingdom > England > Oxfordshire > Oxford (0.14)
- North America > United States > Massachusetts > Middlesex County > Cambridge (0.04)
- North America > United States > New Jersey > Mercer County > Princeton (0.04)
Causal computations in Semi Markovian Structural Causal Models using divide and conquer
Bjøru, Anna Rodum, Cabañas, Rafael, Langseth, Helge, Salmerón, Antonio
Recently, Bjøru et al. proposed a novel divide-and-conquer algorithm for bounding counterfactual probabilities in structural causal models (SCMs). They assumed that the SCMs were learned from purely observational data, leading to an imprecise characterization of the marginal distributions of exogenous variables. Their method leveraged the canonical representation of structural equations to decompose a general SCM with high-cardinality exogenous variables into a set of sub-models with low-cardinality exogenous variables. These sub-models had precise marginals over the exogenous variables and therefore admitted efficient exact inference. The aggregated results were used to bound counterfactual probabilities in the original model. The approach was developed for Markovian models, where each exogenous variable affects only a single endogenous variable. In this paper, we investigate extending the methodology to \textit{semi-Markovian} SCMs, where exogenous variables may influence multiple endogenous variables. Such models are capable of representing confounding relationships that Markovian models cannot. We illustrate the challenges of this extension using a minimal example, which motivates a set of alternative solution strategies. These strategies are evaluated both theoretically and through a computational study.
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- North America > United States > Massachusetts > Middlesex County > Cambridge (0.04)
- North America > United States > California > San Mateo County > Menlo Park (0.04)
- Europe > United Kingdom > England > Cambridgeshire > Cambridge (0.04)
Cyclic Counterfactuals under Shift-Scale Interventions
Saha, Saptarshi, Rathore, Dhruv Vansraj, Garain, Utpal
Most counterfactual inference frameworks traditionally assume acyclic structural causal models (SCMs), i.e. directed acyclic graphs (DAGs). However, many real-world systems (e.g. biological systems) contain feedback loops or cyclic dependencies that violate acyclicity. In this work, we study counterfactual inference in cyclic SCMs under shift-scale interventions, i.e., soft, policy-style changes that rescale and/or shift a variable's mechanism.
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- Europe > United Kingdom > England > Cambridgeshire > Cambridge (0.04)
- North America > United States > Virginia > Arlington County > Arlington (0.04)
- North America > United States > California > Orange County > Irvine (0.14)
- Europe > United Kingdom > England > Cambridgeshire > Cambridge (0.04)
- North America > United States > Montana (0.04)
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- Health & Medicine > Therapeutic Area > Oncology (1.00)
- Health & Medicine > Pharmaceuticals & Biotechnology (1.00)
Intervention and Conditioning in Causal Bayesian Networks
Causal models are crucial for understanding complex systems and identifying causal relationships among variables. Even though causal models are extremely popular, conditional probability calculation of formulas involving interventions pose significant challenges. In case of Causal Bayesian Networks (CBNs), Pearl assumes autonomy of mechanisms that determine interventions to calculate a range of probabilities. We show that by making simple yet often realistic independence assumptions, it is possible to uniquely estimate the probability of an interventional formula (including the well-studied notions of probability of sufficiency and necessity). We discuss when these assumptions are appropriate. Importantly, in many cases of interest, when the assumptions are appropriate, these probability estimates can be evaluated using observational data, which carries immense significance in scenarios where conducting experiments is impractical or unfeasible.
- North America > Greenland (0.04)
- North America > United States > Massachusetts (0.04)
- North America > United States > California > San Francisco County > San Francisco (0.04)
- (2 more...)