Quantitative Methods for Analyzing Second Language Lexical Tone Production

The production of L2 lexical tone has proven difficult for learners of tonal languages, leading to the testing of different tone training techniques. To test the validity of these techniques, it is first necessary to capture the differences between L1 and L2 tone datasets. The current study explores three analyses designed to compare L1 and L2 tone: (1) using a single deviation score, (2) using deviation score calculations for specific regions of tone productions, and (3) applying a complexity-invariant distance measure to the two time series datasets. These three analyses were tested using datasets sampled from a previous study testing the effects of a visual feedback paradigm on the production of L2 Mandarin tone. Results suggest the first two analyses, although useful for providing an overall evaluation of how L2 speakers’ pretest versus posttest productions compare to L1 speakers, lose critical information about tone, namely pitch height, contour, and the timing of the production. The third analysis, applying the complexity-invariant distance measure to the datasets, can provide the pertinent information lost from the first two analyses in a more robust manner.