Multiple Testing Corrections
The Multiple Testing Problem
In causal discovery, we typically test m hypotheses simultaneously:
$$
H_{0,k}: I(X_{j_k}^{(t-\tau_k)}; X_i^{(t)} \mid \mathbf{Z}_i^{(t)}) = 0, \quad k = 1, \ldots, m
$$
Family-Wise Error Rate (FWER):
$$
\text{FWER} = P(\text{at least one false rejection}) = P\left(\bigcup_{k \in \mathcal{H}_0} {p_k \leq \alpha}\right)
$$
False Discovery Rate (FDR):
$$
\text{FDR} = \mathbb{E}\left[\frac{V}{\max(R, 1)}\right]
$$
where (V) is the number of false rejections and (R) is the total number of rejections.
Bonferroni Correction
Method: Reject (H_{0,k}) if (p_k \leq \alpha / m)
Properties:
- Controls FWER exactly: (\text{FWER} \leq \alpha)
- Conservative (low power) when (m) is large
- Appropriate when few true relationships exist
Application in oCSE:
Use when testing a small number of pre-specified relationships or
when strong FWER control is required.
False Discovery Rate Control
Benjamini–Hochberg Procedure:
- Order p-values: (p_{(1)} \leq p_{(2)} \leq \cdots \leq p_{(m)})
- Find largest (k) such that (p_{(k)} \leq \frac{k}{m}\alpha)
- Reject (H_{0,(1)}, \ldots, H_{0,(k)})
Adaptive FDR:
Estimate the proportion of true nulls (\pi_0):
$$
\hat{\pi}_0 = \frac{\text{num}{p_i > \lambda}}{m(1 - \lambda)}
$$
Then use threshold:
$$
p_{(k)} \leq \frac{k}{m \hat{\pi}_0}\alpha
$$
By-Stage Methods:
Control FDR at each stage of forward/backward selection.
Multiple Testing Corrections
The Multiple Testing Problem
In causal discovery, we typically test m hypotheses simultaneously:
Family-Wise Error Rate (FWER):
False Discovery Rate (FDR):
where (V) is the number of false rejections and (R) is the total number of rejections.
Bonferroni Correction
Method: Reject (H_{0,k}) if (p_k \leq \alpha / m)
Properties:
Application in oCSE:
Use when testing a small number of pre-specified relationships or
when strong FWER control is required.
False Discovery Rate Control
Benjamini–Hochberg Procedure:
Adaptive FDR:
Estimate the proportion of true nulls (\pi_0):
Then use threshold:
By-Stage Methods:
Control FDR at each stage of forward/backward selection.