The Random Power Function for Tests Based on Pivotal Quantities

Fulvio De Santis et al.

International Statistical Review2026https://doi.org/10.1111/insr.70031article
AJG 3ABDC A
Weight
0.50

Abstract

Summary In clinical trials planning, evaluation of the probability of success of an experiment is of central interest, for instance, in sample size determination. This assessment typically involves analyses of the power function of a test on a parameter of interest, such as a relevant treatment effect. In this article, we adopt a hybrid frequentist‐Bayesian approach that is lately becoming more and more popular in the literature. Specifically, we focus on superiority trials, and we study the distribution of the power function induced by a design prior assigned to the parameter. Under mild assumptions, we derive general expressions for the cumulative and density functions of the random power in terms of its inverse. We then specialise this result to tests based on pivotal quantities, and we consider some classes of problems, both exact and asymptotic, conventionally employed in clinical trials. Ideas are exposed by resorting to four biomedical settings adapted from real data applications.

Open via your library →

Cite this paper

https://doi.org/https://doi.org/10.1111/insr.70031

Or copy a formatted citation

@article{fulvio2026,
  title        = {{The Random Power Function for Tests Based on Pivotal Quantities}},
  author       = {Fulvio De Santis et al.},
  journal      = {International Statistical Review},
  year         = {2026},
  doi          = {https://doi.org/https://doi.org/10.1111/insr.70031},
}

Paste directly into BibTeX, Zotero, or your reference manager.

Flag this paper

The Random Power Function for Tests Based on Pivotal Quantities

Flags are reviewed by the Arbiter methodology team within 5 business days.


Evidence weight

0.50

Balanced mode · F 0.40 / M 0.15 / V 0.05 / R 0.40

F · citation impact0.50 × 0.4 = 0.20
M · momentum0.50 × 0.15 = 0.07
V · venue signal0.50 × 0.05 = 0.03
R · text relevance †0.50 × 0.4 = 0.20

† Text relevance is estimated at 0.50 on the detail page — for your query’s actual relevance score, open this paper from a search result.