James Dean Brown ("JD"), currently Professor of Second Language Studies at the University of Hawaii at Manoa, has lectured and taught around the world and has published numerous articles and books on language testing, curriculum design, research methods, and connected speech. For close to twenty years, Professor Brown has contributed a regular column called Statistics Corner to Shiken, the biannual publication of the Testing and Evaluation Special Interest Group (TEVAL) of the Japan Association for Language Teaching (JALT). In his column, JD answers questions submitted by readers about language testing and statistics in an informal and easy to understand format. This volume brings together in one convenient location, forty-one Statistics Corner columns-updated, arranged thematically, and fully indexed. Presented in a question and answer format, the clear and concise explanations are both accessible to novices and engaging to experts. Topics addressed include: - Second language testing strategies - Likert items and scales of measurement - Validity and reliability of tests and questionnaires - Item analysis techniques for norm-referenced and criterion-referenced tests - Conducting and interpreting principle component and factor analyses - Planning and interpreting qualitative, quantitative, and mixed-methods research - Clear explanations of the meaning and interpretation of frequently reported statistics such as Cronbach's alpha, standard error, confidence intervals, eta squared, Cohen's Kappa, skewness and kurtosis, and more.