Figure 1a from Smerdon (2011) showing the cross-validated RMSE on 30-year hold out blocks for a subset of the original McShane and Wyner (2011) experiments and for newly completed experiments using the instrumental data perturbed with various levels of noise. The 86% red-noise experiment is considered to be representative of the average proxy predictor [Mann et al. (2007)] and compares well to the proxy result.