Statistička analiza podataka u eksperimentalnim istraživanjima usvajanja drugoga jezika

This book is dedicated to the application of statistical analysis in experimental studies of second language acquisition. In terms of second language acquisition, the focus is on linguistically oriented research, where emphasis is placed on the study of systematic knowledge of the second language and its properties at different levels of the language structure. When it comes to statistics, most attention is dedicated to those concepts and analytical steps that are important for all or most of statistical tests used in research on second language acquisition. Emphasis is also placed on the relationship between descriptive and inferential statistics and the importance of research design for all aspects of data analysis. The book is written as a scientific monograph that can also be used as a manual for beginners who wish to familiarise themselves with basic statistical procedures and the assumptions behind them, applied to the study of linguistic properties of learner language. The topics covered do not require prior knowledge of statistics or in-depth familiarity with issues in second language acquisition. The approach is conceptual rather than practical: no instructions are given on how to perform the analyses in any statistical software and no exercises are included. The book is structured as follows. Chapter 1 explains the motivation behind the book, focusing on the role of statistical analysis in second language acquisition research. Chapter 2 deals with those steps in the research process that precede statistical data analysis. More precisely, it summarises the fundamental methodological matters that should be taken into account when planning an experimental study and associated data analysis, which are related to research hypotheses, variable measurement, the selection of participants and stimuli, and research design. This chapter also describes the steps involved in the preparation of data for statistical analysis and provides guidelines for checking the reliability of the data collection instrument. Chapter 3 is dedicated to descriptive statistics, that is, to the initial description of data via different kinds of descriptive statistical measures, and data visualization using different types of graphs. Chapter 4 builds on the descriptive background of Chapter 3, dealing with inferential statistics. It introduces the notions of statistical significance and null hypothesis testing, explains the logic behind statistical testing and outlines the criteria for choosing a statistical test. Chapter 5 explains the calculation procedures of several frequently used “traditional” tests (such as correlation, t-tests and analysis of variance, as well as their non-parametric equivalents) and it gives a brief overview of some of the more advanced tests, which are increasingly used in language research. This chapter also discusses current issues related to the reliability of significance- -based statistical tests and suggests possible solutions, from more careful interpretation of test results and effect size calculations to reliance on robust statistics. Chapter 6 discusses the reporting of experimental studies of second language acquisition. It provides general guidelines for reporting experimental research and describes the structure of an experimental research report on second language acquisition, primarily focusing on scientific articles for publication in a scientific journal or an edited volume. Finally, Chapter 7 outlines possible future trends in the use of statistics in empirical disciplines such as second language acquisition, and puts forward a call for an integrated consideration of statistical analysis and the field’s theoretical knowledge, and for more thorough methodological training of second language acquisition researchers in our local context.