stop (final-1 -> final, continuation counterfactual)
   no failing check shown       attempts  23  graded score up  0 down  0  mean change +0.000
   shown, >=1 passing at end    attempts  49  graded score up  8 down  4  mean change +0.027
   shown, none passing at end   attempts  48  graded score up  1 down  1  mean change +0.000
early (early-1 -> final, includes ordinary completion)
   no failing check shown       attempts  23  graded score up  7 down  0  mean change +0.139
   shown, >=1 passing at end    attempts  66  graded score up 24 down  3  mean change +0.073
   shown, none passing at end   attempts  31  graded score up  6 down  1  mean change +0.023
