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JAQM Volume 16, Issue 3 - September 30, 2021
Contents
Ordinal Logistic Regression as an alternative analysis strategy for the comparison of two independent samples
B. BILSKI, B. DERRICK, D. TOHER, P. WHITE
The two group between subjects design is pervasive with analyses often performed using the Mann Whitney Rank Sum test or using the Welch variant of the t-test. Using simulation it is shown that a dummy variable ordinal logistic regression (OLR) model provides an alternative analysis strategy for n >= 16 per group retaining Type I error robustness for both continuous and tied data. OLR is demonstrated to have comparable power to the Mann Whitney test under non-normal alternatives and with comparable power to the Welch t-test for normal distributed data. This opens the possibility for the ordinal logistic model to be a general analysis technique for higher order designs.
Romania's rural children most affected by the Covid-19 pandemic
Ionela-Roxana GLĂVAN
The school lock-downs and the shift to online education, may deny children from disadvantage communities or remote locations the opportunity to have an equal change in education and may widen the gaps in terms of learning achievements, obtained competences and curve the future trajectory of the labour market access. The study focuses on the education access for the primary and secondary school children in Romania and investigates impact and inequalities exploiting new data sources collected during the pandemic. The data analysis sugests that the effect of COVID-19 pandemic will be felt intensively by children for time to come. Lack of infrasstructure and apropriate digital tools to facilitate online schooling exposed serious risks in creating an unequal enviroment which on the long term might never be recovered by most of the affected children. Having in mind that digitalisation is a necesity for a developed and modern economy, there is still room for improvements as the Romanian educational system should also be integrated with the appropriate infrastructure, tools and services necessary for no child to be left behind in the forthcoming 4th digital revolution.
Estimation of the two-group pilot sample size with a cautionary note on Browne’s formula
Scholastica OBODO, Deirdre TOHER, Paul WHITE
Using data obtained from a pilot study, Browne (1995) proposed a procedure for estimating the sample size needed for a definitive two-arm randomised controlled trial when the minimal important difference is specified. Simulations confirm these findings. The results attributable to Browne are extended to consider the degree of error attached to sample size estimation using this procedure. A consideration of the error provides a simple mechanism to estimate the sample size needed for a pilot study so as to control the degree of error in the follow-on substantive trial.