Fig. 12From: Improvements and validation of the IRI UP method under moderate, strong, and severe geomagnetic stormsPercentage of variogram models discarded by the NQCR procedure. Percentage of discarded variogram models for (top) each storm listed in Table 3 and (bottom) all storms as a whole, for (left) foF2 and (right) hmF2. On the top panels the percentage of the linear model is not visible because hidden by the power modelBack to article page