Lexical Complexity Analyzer

This web-based Lexical Complexity Analyzer takes up to 2 samples of English text, and generates 25 indices of lexical complexity. You can select any or all of the 25 measures, and the system will create a graphical representation to visualize your results. By uploading two different text, you can compare the longitudinal development of L2 learner's performance or compare L2 learner's performance against native speaker.

By accessing and using the Lexical Complexity Analyzer, you are acknowledging that you agree to be legally bound and to abide by the LCA Terms of Service.

L2 Syntactical Complexity Analyzer

This web-based L2 Syntactical Complexity Analyzer takes up to 2 samples of English text, and counts the occurrences of the following 9 structures in the text(s): words (W), sentences (S), verb phrases (VP), clauses (C), T-units (T), dependent clauses (DC), complex T-units (CT), coordinate phrases (CP), and complex nominals (CN). These frequency counts are then used to compute the following 14 syntactic complexity indices of the text(s): mean length of sentence (MLS), mean length of T-unit (MLT), mean length of clause (MLC), clauses per sentence (C/S), verb phrases per T-unit (VP/T), clauses per T-unit (C/T), dependent clauses per clause (DC/C), dependent clauses per T-unit (DC/T), T-units per sentence (T/S), complex T-unit ratio (CT/T), coordinate phrases per T-unit (CP/T), coordinate phrases per clause (CP/C), complex nominals per T-unit (CN/T), and complex nominals per clause (CN/C). You can select any or all of the 23 measures, and the system will create a graphical representation to visualize your results. By uploading two different text, you can compare the longitudinal development of L2 learner's performance or compare L2 learner's performance against native speaker.

By accessing and using the L2 Syntactic Complexity Analyzer, you are acknowledging that you agree to be legally bound and to abide by the L2SCA Terms of Service.


For L2 Syntactical Complexity Analyzer, please cite:

  • Lu, Xiaofei (2010). Automatic analysis of syntactic complexity in second language writing. International Journal of Corpus Linguistics, 15.

For Lexical Complexity Analyzer, please cite:

  • Ai, Haiyang and Lu, Xiaofei (2010). A web-based system for automatic measurement of lexical complexity. Paper presented at the 27th Annual Symposium of the Computer-Assisted Language Consortium (CALICO-10). Amherst, MA. June 8-12.
  • Lu, Xiaofei (forthcoming). The Relationship of Lexical Richness to the Quality of ESL Learners' Oral Narratives. The Modern Language Journal.

Please inform Professor Xiaofei Lu (mailto: xxl13@psu.edu) when you have published or presented work that used the Lexical Complexity Analyzer and/or the L2 Syntactical Complexity Analyzer.