https://matteocampagna.com/en/registry/competition/level-tighter-centred-group Changes to this claim in Matteo Campagna's evidence registry: its status, its year-by-year history, revisions of the page. en-gb https://matteocampagna.com/en/registry/competition/level-tighter-centred-groupSeven independent samples all point the same way, and none the other. At eighteen metres the group outline of three Olympic archers runs from 7.8 to 10 cm, that of six national-level archers from 11.9 to 26.7, about twice as large on average. Over seventy-two arrows each, again at eighteen metres, the spread of beginners' impacts is five to seven times that of high-level archers, whose mean impact also sits closest to the centre; centring does not fall in step with level, though, because the middle group is the most off-centre of the three. At thirty metres ten Olympic-level archers are more precise than ten beginners while taking the same time per shot. The same thing shows inside a single national squad, read on the score alone: over ninety arrows the best archer shot neither a six nor a seven, the worst shot fourteen sevens and a six, and between national-squad and provincial-squad archers the gap is 8.7 against 6.8 points per arrow, with very different consistency. In competition, on photographs of the target faces at two major events in 2013, the top twenty men's compound archers lose 0.30 points over 36 arrows to an off-centre group, against 1.35 for their division as a whole. What keeps the status low is the design: these are all cross-sectional comparisons between different groups, two of the studies are congress abstracts, one with no figures and the other with no units, and in competition the better centring of the leading archers shows clearly only in men's compound.claim:livello-gruppo-stretto-centrato:revision:2026-07-30:2Thu, 30 Jul 2026 08:00:00 GMT https://matteocampagna.com/en/registry/competition/level-tighter-centred-group#storiaPhotographs of the target faces at two major competitions in 2013, reread through a model, add centring measured in competition: archers centre their group to within about 60 per cent of its size, and in men's compound the top twenty lose 0.30 points over 36 arrows to off-centre groups against 1.35 on average. It is the sixth sample pointing the same way and none points the other, but this too is a comparison between different archers at the same competition: the status stays reported.claim:livello-gruppo-stretto-centrato:history_entry:2026-07-29:2020Wed, 29 Jul 2026 08:00:00 GMT https://matteocampagna.com/en/registry/competition/level-tighter-centred-groupclaim:livello-gruppo-stretto-centrato:new_claim:2026-05-11:riportatoMon, 11 May 2026 08:00:00 GMT