Statistical tests carry with them a number of assumptions that must be checked. Failing to do so and to report the results of such preliminary analyses introduce a potential threat to the internal validity of a study and to our ability as consumers to put faith in study findings. This article systematically examines the reporting of checks on…

First, we trace the history of second language acquisition (SLA) from early stages in the mid-twentieth century to today. We next consider the status of the field in today's research world with a particular focus on all aspects of methodology and, finally, we take a look at the future and discuss issues related to scientific rigor in light of Open…

A third level of educational research is emerging, in addition to original research and secondary-level reviews. Whereas most third-level research syntheses focus on rather restricted topical areas, this study introduces a comparative and integrative overview of prominent second-order research on teaching, including many different types of reviews…

The research of Systemic Functional Linguistics has been quite in-depth in both theory and practice. However, many linguists hold that Systemic Functional Linguistics has no hypothesis testing or experiments and its research is only qualitative. Analyses of the corpus, intelligent computing and language evolution on the ideological background of…

Adequate reporting of quantitative research about language learning involves careful consideration of the logic, rationale, and actions underlying both study designs and the ways in which data are analyzed. These guidelines, commissioned and vetted by the board of directors of "Language Learning," outline the basic expectations for…

Traditions of statistical significance testing in second language (L2) quantitative research are strongly entrenched in how researchers design studies, select analyses, and interpret results. However, statistical significance tests using "p" values are commonly misinterpreted by researchers, reviewers, readers, and others, leading to…

The advent of usage-/exemplar-based approaches has resulted in a major change in the theoretical landscape of linguistics, but also in the range of methodologies that are brought to bear on the study of language acquisition/learning, structure, and use. In particular, methods from corpus linguistics are now frequently used to study distributional…

Ensuring internal validity in quantitative research requires, among other conditions, reliable instrumentation. Unfortunately, however, second language (L2) researchers often fail to report and even more often fail to interpret reliability estimates beyond generic benchmarks for acceptability. As a means to guide interpretations of such estimates,…

Second language acquisition researchers often face particular challenges when attempting to generalize study findings to the wider learner population. For example, language learners constitute a heterogeneous group, and it is not always clear how a study's findings may generalize to other individuals who may differ in terms of language background…

Good practice in primary research has evolved over many decades of research in applied linguistics to counter human fallibility and biases. Surprisingly, perhaps, synthesising such research in an entire field has only recently started to develop its own methodologies and recommendations. This paper outlines some of the issues involved, especially…

Parametric analyses such as t tests and ANOVAs are the norm--if not the default--statistical tests found in quantitative applied linguistics research (Gass 2009). Applied statisticians and one applied linguist (Larson-Hall 2010, 2012; Larson-Hall and Herrington 2010), however, have argued that this approach may not be appropriate for small samples…

This paper presents a set of guidelines for reporting on five types of quantitative data issues: (1) Descriptive statistics, (2) Effect sizes and confidence intervals, (3) Instrument reliability, (4) Visual displays of data, and (5) Raw data. Our recommendations are derived mainly from various professional sources related to L2 research but…

Children acquiring a range of languages have difficulties in the interpretation of personal pronouns. Ongoing debates in the relevant literature concern the extent to which different pronoun types are subject to this phenomenon, as well as the role of methodology in relevant research. In this study, we use two different experimental tasks to…

Research synthesis and meta-analysis provide a pathway to bring together findings in a given domain with greater systematicity, objectivity, and transparency than traditional reviews. The same techniques and corresponding benefits can be and have been applied to examine methodological practices in second language (L2) research (e.g., Plonsky,…

In empirical applied linguistics research it is essential that the key variables are operationalized in a valid and reliable way, and that the scores are treated appropriately, allowing for a proper testing of the hypotheses under investigation. The current article addresses several theoretical and practical issues regarding the use of measurement…