Figure-of-merit of ionospheric maps for use in propagation assessments

Despite the intuitive feelings by the originators of the URSI maps of their superiority, the CCIR community could not be convinced to adopt these as a replacement for the maps already in use. The position today remains unchanged. Although there are no international efforts under way to generate further global maps, some studies are known to be in train to produce improved regional maps, in particular geographical areas. So this points to the need to review critically the adopted map-testing procedure. The paper makes proposals through the use of appropriate weighting factors to allow comparisons involving a mix of different types of measurement data