FIGURE 2.

The plots of (A) the absolute relative biases (biases divided by β); (B) the empirical standard errors; and (C) the coverage probabilities of the 95% confidence intervals for the dIVW estimator and the pIVW estimator (${\lambda }_{opt}=1$) against the effective sample size η. The dashed line shows $\eta =5$. The dots represent the simulation results under different settings of parameters based on 10,000 replicates. There is no horizontal pleiotropy ($\tau =0$) or IV selection. This figure appears in color in the electronic version of this article, and any mention of color refers to that version