The low agreement at the level of individual publications supports the idea that metrics should generally not replace peer review in the evaluation of a single individual publication. However, the goal of the REF is not to assess the quality of individual publications but rather to assess “the quality of research in UK higher education institutions”[^9]. Therefore, the question should not be whether the evaluation of individual publications by peer review can be replaced by the evaluation of individual publications by metrics but rather whether the evaluation of institutions by peer review can be replaced by the evaluation of institutions by metrics. Even if citations are not sufficiently accurate at the individual publication level, they could still be sufficiently accurate at the aggregate institutional level; the errors may ‘cancel out’. For this reason, we perform our analysis at the institutional level. We calculate citation metrics per combination of an institution and a UoA.

Size-dependent and size-independent perspectives {#sec:size_dependent}
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As briefly discussed earlier, the REF has multiple objectives. It aims to provide a reputational yardstick, but it also aims to provide a basis for distributing funding. A reputational yardstick is usually related to the average scientific quality of the publications 