“…Such confidence sequences have been developed under very general nonparametric, multivariate, matrix, and continuoustime settings using generalizations of the aforementioned supermartingale technique (39)(40)(41). The connections between anytime-valid P values, e values, safe tests, peeking, confidence sequences, and the properties of optional stopping and continuation have been explored recently (35,40,42,43). The connection to the present work is that when run sequentially, our universal (MLE or RIPR) split LRT yields an anytime-valid P value, an e value, and a safe test, which can be inverted to form universal confidence sequences and are valid under optional stopping and continuation, and these are simply because the underlying process of interest is bounded by a nonnegative (super)martingale.…”