Fig. 2
From: Re-expressing coefficients from regression models for inclusion in a meta-analysis
Plots of relative bias as a function of skewness (σ) in the exposure x, by type of estimator. Individual points represent the average result (nsim = 2000) for each simulation scenario. A total of 890 of the possible 1,920,000 observations (960 scenarios × 2000 simulations) were not used in the calculation of the average results because βestimand was < 0.0001 (essentially zero). Lines represent quadratic fits to the data for a specified prediction equation and set of values of independent variables (see text). Note that data have been artificially spread along the x-axis for visualization purposes, all actual x-values are the closest black vertical line (0.25, 0.45, 0.65, or 0.85). Figures A-C show points for 768 simulation scenarios (βDGM > 0, see Figure S1 for plots including βDGM < 0); Figure D shows points for a subset of scenarios (n = 32) chosen because they demonstrate differences among the estimator properties. A Rodriguez-Barranco estimator, B Dzierlenga estimator, and C Alternative estimator. D Shows all 3 estimators in the same plot with a subset of the data of the simulation data where βDGM = 0.5, log base = 2 or 10, and median value = 0.5 or 8