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We do not dismiss this. We report the TOTAL effect (real: +9.3pp, p=0.017), we show the result holds with size measured 1985-99 (predetermined \u2014 2000-23 volatility cannot cause 1985-99 market size), and we show that small PRIMARY metals are just as volatile as small by-product metals, which mediation cannot explain. What we CANNOT settle here is whether companionality contributes to smallness itself. 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Only ~40 metals have a published price series at all, so no amount of work gets this to n=300. More metals do not exist. This bound applies equally to the published 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metals ARE more volatile \u2014 that total effect is real (+9.3pp, p=0.017). But it is fully accounted for by market size: conditional on scale, by-product status adds nothing (+0.9pp, p=0.85), and small PRIMARY metals (rare earths 50%, tantalum 45%, beryllium 43%) are just as volatile as small by-product metals (+1.7pp, p=0.75). Smallness is SUFFICIENT for volatility without companionality. So there is no volatility penalty specific to being a by-product. It holds under HC3, a permutation test, a rank-based model, a physical-tonnes control, dropping contested classes, drop-one, every non-overlapping window from 5 to 24 years, and with size measured 1985-99 (predetermined, so 2000-23 volatility cannot have caused it). HONEST LIMIT: if companionality itself makes a market small, size is a mediator and this design cannot see that channel \u2014 we report the total effect for exactly that reason. What dies is the claim that inelasticity shows up as turbulence over and above scale. NOTE for anyone rerunning this: rolling OVERLAPPING windows appear to reverse the result (by-product +7.8pp, p=0.07) \u2014 that is pseudo-replication, each return reused up to 4x. The same window without overlap gives +1.5pp, p=0.70. By-product status is also time-invariant, so a panel adds no information about it: naive unclustered panel SEs report p<0.0001 on n=614, but clustering by metal returns the effective sample to 33.","mean_vol_byproduct":29.9,"mean_vol_primary":24.9,"excess_vol_pct":20.0,"n_byproduct":6,"n_primary":15,"redlinger_eggert_excess":50,"survives_control":false,"coef_shrink_pct":15.0,"size_significant":false,"baci_crosscheck":{"n":27,"r":0.13,"p":0.5183},"admin_note":"Pre-2000 USGS nominal series for the minor metals are administered list prices (frozen 8-13 years); deflating them manufactures fake real volatility, concentrated in exactly the by-product metals. Window restricted to 2000-2023, where every series is market-priced.","dropped":[{"label":"hafnium","title":"Hafnium","reason":"no world-production series -> no market-size control"},{"label":"titanium","title":"Titanium","reason":"no world-production series -> no market-size control"},{"label":"fluorspar","title":"Fluorspar","reason":"only 6 usable price years in 2000-2023"},{"label":"niobium","title":"Niobium","reason":"only 0 usable price years in 2000-2023"}],"rows":[{"label":"vanadium","title":"Vanadium","usgs":"vanadium","class":"byproduct","companionality_pct":90,"volatility":51.7,"n_returns":22,"market_value_usd":1362300000,"price_real_2023":20300,"chg_real":199.4,"yr_first":2000,"yr_last":2022,"shared_series":false,"administered":false,"in_regression":true},{"label":"magnets","title":"Rare earths / 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