Table 1.

Summary of TDR analysis for binary genotypes and covariates

	Approach
Model	Include Z	Stratify by Z	Residualize by Z	Ignore Z
1. ADDITIVE	+/+	+/+	+/+	+/+
2. ADDITIVE WITH CONFOUNDING	++/+	+/+	+/+	++/++
3. ADDITIVE WITH EFFECT MEDIATOR	- -/- -	- -/- -	- -/- -	-/-
4. INTERACTION WITH MAIN EFFECTS	++/++	++/++	++/++	++/++
5. INTERACTION WITH NO MAIN EFFECTS	+/++	+/++	-/+	-/+
6. CONDITIONAL ASSOCIATION	+/+	+/+	-/+	-/+

Summary of simulation results in Figures 1 and 2: Results are given in pairs corresponding to RF and MARS respectively; a "+" indicates reasonable TDR (≥ 80%) for detecting moderate effect sizes (≥ 0.5); "++" indicates reasonable TDR (≥ 80%) for detecting small effect sizes (≥ 0.3);"-" indicates lower TDR (50% to 80%) for moderate effect sizes; and '--" indicates very low TDR (< 20%) at moderate effect sizes. Correlation between X₁ and Z is fixed at 0.5 for MODEL 2.