Figure 2
From: Derivation and assessment of risk prediction models using case-cohort data
Unweighted and weighted versions of Harrell’s C-index and Royston and Sauerbrei’s D measure. Predictions are formed using a model in which the Prentice weighting scheme is applied. Graphs show the mean over 1000 selections of the subcohort at each sampling fraction for a) the standard unweighted methods and the weighted versions, and b) the proposed weighted versions with 95% confidence intervals calculated using the empirical standard errors.