(ii) A note on the interpretation quasi-sufficiency
Manuel Bartlett · Biometrika · 1940
In a theoretical note on the interpretation of quasi-sufficient statistics in problemsof one unknown parameter,it is agreedwith Welch that full sufficiency properties can only be claimed if we deliberately confine our attention to conditional samples of the type observed; but it is pointed out that the resulting inferences are independent of any selection operating on tehe variables that have been fixed.