Diverse samples are valuable to the study of development, and to psychology more broadly. But convenience samples--typically recruited from local populations close to universities--are still the most widely used in developmental science, despite the fact that their use leads to a vast over-representation of Western, White, and high socio-economic…

The "School Strike 4 Climate" is a timely opportunity for education and research sectors to support youth stories in climate change policy, and foster impactful relationships between researchers, teachers and students. But much research in this space has inherent selection biases where youth representation in research is limited by place…

The purpose of this paper is to analyze the use of the exemplar methodology (ExM) as a method for selecting exemplars in education research. ExM is a systematic approach to selecting outliers that can be used to education researchers who investigate outliers to better understand phenomena among students, teachers, schools, and communities. While…

There has been considerable recent interest in methods of determining sample size for qualitative research a priori, rather than through an adaptive approach such as saturation. Extending previous literature in this area, we identify four distinct approaches to determining sample size in this way: rules of thumb, conceptual models, numerical…

In his detailed response to our paper on sample size in qualitative research, Norman Blaikie raises important issues concerning conceptual definitions and taxonomy. In particular, he points out the problems associated with a loose, generic application of adjectives such as 'qualitative' or 'inductive'. We endorse this concern, though we suggest…

Although over the past decades the numbers of studies investigating international student mobility and migration (ISM) increased, methodological challenges in empirical research on the topic have remained mainly unaddressed. This is particularly the case for sampling, which is a crucial but often less considered part of qualitative research…

Snowball sampling is frequently advocated and employed by qualitative social researchers. Under certain circumstances, however, it is prone to faltering and even failure. Drawing on two research projects where the snowball failed to roll, the paper identifies reasons for this stasis. It goes on to argue that there are alternative forms of…

Recently, Stephen Gorard has outlined strong objections to the use of significance testing in social research. He has argued, first, that as the samples used in social research are almost always non-random it is not possible to use inferential statistical techniques and, second, that even if a truly random sample were achieved, the logic behind…

Outdoor adventure education (OAE) has a long history of being credited with the personal and social development (PSD) of its participants. PSD is notoriously difficult to measure quantitatively, yet stakeholders demand statistical evidence that given approaches to eliciting PSD are effective in their methods. Rightly or wrongly, many stakeholders…

In educational research that calls itself empirical, the relationship between validity and reliability is that of trade-off: the stronger the bases for validity, the weaker the bases for reliability (and vice versa). Validity and reliability are widely regarded as basic criteria for evaluating research; however, there are ethical implications of…

Studies of the effects of class attendance on class performance typically are quasi-experimental because students choose whether or not to attend class; that is, the samples are self-selecting. The lack of random assignment prevents one from establishing a causal relationship between attendance and performance. Relating attendance to performance…

In this article, the authors review International Large-Scale Assessment (ILSA)-based research over the last several decades, with specific attention on cross-national analysis of mean differences between and variation within countries in mathematics education. They discuss the role of sampling design and "opportunity to learn" (OTL)…

Gay, lesbian, bisexual, transgender, questioning and inter-sex (GLBTQI) youth, and those perceived to be GLBTQI, face extensive verbal and physical bullying in schools. Although increasing attention has been made at examining the safety concerns of sexual minority (GLBTQI) youth, there remain important gaps in the literature as well as significant…

Studies of group differences in intelligence often invite conclusions about groups in general from studies of group differences in selected populations. The same design is used in the study of group differences in other traits as well. Investigators observe samples from two groups (e.g. men and women) in some accessible population, but seek to…

This technical paper examines the issue of attrition bias in two cohorts of the Longitudinal Surveys of Australian Youth (LSAY), based on an analysis using data from 1995 to 2002. Data up to 2002 provided eight years of information on members of the Y95 cohort and five years of information on members of the Y98 cohort. This study suggests that…