A nuclear physics example of statistical bootstrap is used on the MARATHON nucleon structure function ratio
data in the quark momentum fraction regions xB → 0 and xB → 1. The extrapolated F2 ratio as quark momentum
fraction xB → 1 is Fn
2
F p
2
→ 0.4 ± 0.05 and this value is compared to theoretical predictions. The extrapolated ratio
when xB → 0 favors the simple model of isospin symmetry with the complete dominance of sea quarks at low
momentum fraction. At high-xB, the proton quark distribution function ratio d/u is derived from the F2 ratio
and found to be d/u → 1/6. Our extrapolated values for both the Fn
2
F p
2
ratio and the d/u parton distribution
function ratio are within uncertainties of perturbative QCD values from quark counting, helicity conservation
arguments, and a Dyson-Schwinger equation with a contact interaction model. In addition, it is possible to match
the statistical bootstrap value to theoretical predictions by allowing two compatible models to act simultaneously
in the nucleon wave function. One such example is nucleon wave functions composed of a linear combination
of a quark-diquark state and a three-valence quark correlated state with coefficients that combine to give the
extrapolated F2 ratio at xB = 1.
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Learning Predictions for Algorithms with Predictions
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