This is why weighting models need to be made explicit and transparent.
Weights usually have an important impact on the composite indicator value and on the resulting ranking, especially whenever higher weight is assigned to indicators on which some countries excel or fail. Different weights may be assigned to component series in order to reflect their economic significance (collection costs, coverage, reliability and economic reason), statistical adequacy, cyclical conformity, speed of available data, etc. No uniformly agreed methodology exists to weight individual indicators before aggregating them into a composite indicator.
