Fig 7. Performance of slidingwin in estimating the true R² value of a climate signal.

Performance determined at varying sample sizes with very high R² (0.80; left), high R² (0.40; centre), and moderate R² (0.20; bottom) both without cross-validation (black) and with 10-fold cross-validation (white). Points represent median R² estimates from 2,000 simulated datasets. Error bars represent inter-quartile range. The horizontal dashed line shows the true value of R² used to generate the simulated datasets.