Unequal sample size allocation to optimal design for binomial logistic models

1987 ◽  
Vol 28 (1) ◽  
pp. 285-290 ◽  
Author(s):  
R. K. Jain
CATENA ◽  
2021 ◽  
Vol 206 ◽  
pp. 105509
Author(s):  
Shuangshuang Shao ◽  
Huan Zhang ◽  
Manman Fan ◽  
Baowei Su ◽  
Jingtao Wu ◽  
...  

1974 ◽  
Vol 3 (11) ◽  
pp. 1025-1040
Author(s):  
J. Sedransk ◽  
Bahadur Singh

2021 ◽  
Author(s):  
Metin Bulus

A recent systematic review of experimental studies conducted in Turkey between 2010 and 2020 reported that small sample sizes had been a significant drawback (Bulus and Koyuncu, 2021). A small chunk of the studies were small-scale true experiments (subjects randomized into the treatment and control groups). The remaining studies consisted of quasi-experiments (subjects in treatment and control groups were matched on pretest or other covariates) and weak experiments (neither randomized nor matched but had the control group). They had an average sample size below 70 for different domains and outcomes. These small sample sizes imply a strong (and perhaps erroneous) assumption about the minimum relevant effect size (MRES) of intervention before an experiment is conducted; that is, a standardized intervention effect of Cohen’s d < 0.50 is not relevant to education policy or practice. Thus, an introduction to sample size determination for pretest-posttest simple experimental designs is warranted. This study describes nuts and bolts of sample size determination, derives expressions for optimal design under differential cost per treatment and control units, provide convenient tables to guide sample size decisions for MRES values between 0.20 ≤ Cohen’s d ≤ 0.50, and describe the relevant software along with illustrations.


1989 ◽  
Vol 19 (12) ◽  
pp. 1591-1597
Author(s):  
Margaret Penner

A method for incorporating variable costs and differing precision requirements into optimal design theory is developed and discussed. In many studies and experiments, particularly in the biological sciences, the cost of each observation can vary considerably depending on the attributes of the sample. Ignoring observation costs leads to designs that maximize precision for a given sample size. However, by incorporating costs, efficiency is maximized by optimizing precision per unit cost. An example is presented that demonstrates the efficiency of a weighted optimal design in comparison with several alternatives. The weighted optimal design is most efficient at meeting the experimenter's precision objectives. Comparing designs allows the introduction of additional criteria such as design flexibility into the evaluation process. Explicitly incorporating both cost and precision in the search for a sampling design ensures time is wisely spent considering study objectives, including precision requirements.


2019 ◽  
Vol 12 (08) ◽  
pp. 1950086
Author(s):  
Carlos N. Bouza-Herrera ◽  
Sira M. Allende-Alonso ◽  
Gajendra K. Vishwakarma ◽  
Neha Singh

In many medical researches, it is needed to determine the optimal sample size allocation in a heterogeneous population. This paper proposes the algorithm for optimal sample size allocation. We consider the optimal allocation problem as an optimization problem and the solution is obtained by using Bisection, Secant, Regula–Falsi and other numerical methods. The performance of the algorithm for different numerical methods are analyzed and evaluated in terms of computing time, number of iterations and gain in accuracy using stratification. The efficacy of algorithm is evaluated for the response in terms of body mass index (BMI) to the dietetic supplement with diabetes mellitus, HIV/AIDS and cancer post-operatory recovery patients.


1999 ◽  
Vol 20 (6) ◽  
pp. 555-566 ◽  
Author(s):  
John J. Hanfelt ◽  
Rebecca S. Slack ◽  
Edmund A. Gehan

2017 ◽  
Vol 60 (1) ◽  
pp. 155-173 ◽  
Author(s):  
Pier Francesco Perri ◽  
María del Mar Rueda García ◽  
Beatriz Cobo Rodríguez

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