Several branches of the potential outcome causal inference literature have discussed the merits of blocking versus complete randomization. Some have concluded it can never hurt the precision of estimates, and some have concluded it can hurt. In this article, we reconcile these apparently conflicting views, give a more thorough discussion of what…

In single-case research designs (SCDs) to determine a functional relation a time-series graph is constructed. Preliminary evidence suggest the approach used to scale the vertical axis and the data points per x- to y-axis ratio (DPPXYR) impact visual analysts' decisions. We conducted a systematic review to evaluate time-series graphs published in…

This article serves as an overview of qualitative inquiry for leadership development practitioner-scholars both new and experienced. It begins with a discussion of the need for the qualitative inquiry to create knowledge about leadership development. Then, it overviews design components and includes examples of both research and assessment. We…

In education settings, treatments are often non-randomly assigned to clusters, such as schools or classrooms, while outcomes are measured for students. This research design is called the clustered observational study (COS). We examine the consequences of common support violations in the COS context. Common support violations occur when the…

Enzyme kinetics and inhibition studies are crucial in biochemistry education and research. Conventional methods often require expensive equipment and reagents, potentially limiting their accessibility in limited resource settings. Our approach sought to develop a cost-effective experimental design for studying enzyme kinetics and inhibition.…

Children's fears have received scholarly attention for well over 50 years. A considerable amount of literature has focused on such fear variables as fear intensity and fear prevalence scores and age and gender differences. We used meta-analysis to systematically review the findings related to gender differences in children's fear intensity scores…

Purpose: The lack of a definite standard for determining the sample size in qualitative research leaves the research process to the initiative of the researcher, and this situation overshadows the scientificity of the research. The primary purpose of this research is to propose a model by questioning the problem of determining the sample size,…

This review aimed to synthesize the group design literature to identify the evidence-based reading comprehension interventions for children with ASD. The primary aim was to identify which reading comprehension interventions had demonstrated positive effects for students with ASD in group design studies. This review was initiated using both…

Family income questions in general purpose surveys are usually collected with either a single-question summary design or a multiple-question disaggregation design. It is unclear how estimates from the two approaches agree with each other. The current paper takes advantage of a large-scale survey that has collected family income with both methods.…

This paper grapples with methodological issues related to ongoing debates on positionality and reflexivity by drawing on the author's experience of conducting research in a culturally familiar field. The paper is based on in-depth qualitative research that examined the lived realities of unemployed young people residing in the township of Daveyton…

COVID-19 led to an increase in online higher education courses. With this increase in demand, there needs to be online support to foster students' academic success. Online academic student support is often provided to students to assist them in developing the skills and knowledge to successfully complete their courses. However, it remains unclear…

Planning longitudinal studies can be challenging as various design decisions need to be made. Often, researchers are in search for the optimal design that maximizes statistical power to test certain parameters of the employed model. We provide a user-friendly Shiny app OptDynMo available at https://shiny.psychologie.hu-berlin.de/optdynmo that…

Grouped and right-censored (GRC) counts have been used in a wide range of attitudinal and behavioural surveys yet they cannot be readily analyzed or assessed by conventional statistical models. This study develops a unified regression framework for the design and optimality of GRC counts in surveys. To process infinitely many grouping schemes for…

Motivation to read is a central consideration for teachers and researchers because it is strongly associated with reading performance and is generally accepted as a positive state. The study of reading motivation is plagued by inconsistent terminology and measurement, which impedes a comprehensive knowledge base for teachers and researchers. One…

Background: Power analyses for a cluster-randomized trial (CRT) require estimates of additional design parameters beyond those needed for an individually randomized trial. In a 2-level CRT, there are two sample sizes, the number of clusters and the number of individuals per cluster. The intraclass correlation (ICC), or the proportion of variance…