scholarly journals Statistical Decisions

2021 ◽  
pp. 113-153
Author(s):  
Göran Kauermann ◽  
Helmut Küchenhoff ◽  
Christian Heumann
Economica ◽  
1955 ◽  
Vol 22 (87) ◽  
pp. 279
Author(s):  
M. Shubik ◽  
David Blackwell ◽  
M. A. Girshick

2006 ◽  
Vol 1 (4) ◽  
pp. 3 ◽  
Author(s):  
Li Zhang ◽  
Margaret Sampson ◽  
Jessie McGowan

Introduction - This study applied the principles of evidence based information practice to clarify the role of information specialists and librarians in the preparation of Cochrane systematic reviews and to determine whether information specialists impact the quality of searching in Cochrane systematic reviews. Objectives - This research project sought to determine how the contribution of the person responsible for searching in the preparation of Cochrane systematic reviews was reported; whether the contribution was recognized through authorship or acknowledgement; the qualifications of the searcher; and the association between the type of contributorship and characteristics of the search strategy, assessability, and the presence of certain types of errors. Methods - Data sources: The Cochrane Database of Systematic Reviews, The Cochrane Library 3 (2002). Inclusion criteria: The study included systematic reviews that met the following criteria: one or more sections of the Cochrane Highly Sensitive Search Strategy were utilised, primary studies were either randomised controlled trials (RCTs) or quasi-RCTs, and included and excluded studies were clearly identified. Data extraction: Two librarians assessed the searches for errors, establishing consensus on discordant ratings. Results - Of the 169 reviews screened for this project, 105 met all eligibility criteria. Authors fulfilled the searching role in 41.9% of reviews studied, acknowledged persons or groups in 13.3%, a combination in 9.5%, and the role was not reported in 35.2% of reviews. For the 78 reviews in which meta-analyses were performed, the positions of those responsible for statistical decisions were examined for comparative purposes. The statistical role was performed by an author in 47.4% of cases and unreported in the same number of cases. Insufficient analyzable data was obtained regarding professional qualifications (3/105 for searching, 2/78 for statistical decisions). Search quality was assessed for 66 searches across 74 reviews. In general, it was more possible to assess the search quality when the searcher role was reported. An association was found between the reporting of searcher role and the presence of a consequential error. There was no association between the number of consequential errors and how the contribution of the searcher was reported. Conclusions - Qualifications of the persons responsible for searching and statistical decision-making were poorly reported in Cochrane reviews, but more complete role reporting is associated with greater assessability of searches and fewer substantive errors in search strategies.


Author(s):  
D. V. Lindley ◽  
Morris de Groot

1986 ◽  
pp. 308-343
Author(s):  
Didier Dacunha-Castelle ◽  
Marie Duflo

Author(s):  
N. A. Nechval ◽  
K. N. Nechval

In this chapter, an innovative model for age replacement is proposed. The costs included in the age replacement model are not assumed to be constants. For effective optimization of statistical decisions for age replacement problems under parametric uncertainty, based on a past random sample of lifetimes, the pivotal quantity averaging (PQA) approach is suggested. The PQA approach represents a simple and computationally attractive statistical technique. In this case, the transition from the original problem to the equivalent transformed problem (in terms of pivotal quantities and ancillary factors) is carried out via invariant embedding a sample statistic in the original problem. The approach allows one to eliminate unknown parameters from the problem and to find the better decision rules, which have smaller risk than any of the well-known decision rules. Unlike the Bayesian approach, the proposed approach is independent of the choice of priors. For illustration, numerical examples are given.


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