Correlational analysis of ordinal data: from Pearson’s r to Bayesian polychoric correlation

Correlational analyses are one of the most popular quantitative methods, yet also one of the mostly frequently misused methods in social and behavioral research, especially when analyzing ordinal data from Likert or other rating scales. Although several correlational analysis options have been developed for ordinal data, there seems to be a lack of didactically written literature illustrating the appropriate use and differences among them. The purpose of this paper is to provide a synthesis of correlational analysis options when analyzing ordinal data. These options span from the traditional methods, such as Pearson’s r, to more recent developments, such as Bayesian estimation of polychoric correlations. An illustration of these methods utilizing a contemporary dataset is provided.     

Undergraduate students' ability to revise text effectively: relationships with topic knowledge and working memory

In order to communicate understanding, students are often required to produce texts which present an explicit, coherent argument. This study examined the extent to which individual differences in undergraduates' topic knowledge and working memory skills were related to their ability to revise texts to better fulfil these goals. Forty-seven students revised texts containing three types of error: language, structure and argument. Topic knowledge was indexed by multiple choice test performance. Verbal short-term and working memory were measured using forward and backward digit recall and reading span. Rates of identification, diagnosis and correction of errors were generally poor. Contrary to expectations neither topic knowledge nor verbal working memory was associated with text revision although significant associations were identified with verbal short-term memory. When revising texts students may focus on the surface features of the text rather than addressing issues of structure and argument. Possible accounts of this tendency are considered.