title: Using Student Writing and Lexical Analysis to Reveal Student Thinking about the Role of Stop Codons in the Central Dogma.
abstract: Previous work has shown that students have persistent difficulties in understanding how central dogma processes can be affected by a stop codon mutation. To explore these difficulties, we modified two multiple-choice questions from the Genetics Concept Assessment into three open-ended questions that asked students to write about how a stop codon mutation potentially impacts replication, transcription, and translation. We then used computer-assisted lexical analysis combined with human scoring to categorize student responses. The lexical analysis models showed high agreement with human scoring, demonstrating that this approach can be successfully used to analyze large numbers of student written responses. The results of this analysis show that students' ideas about one process in the central dogma can affect their thinking about subsequent and previous processes, leading to mixed models of conceptual understanding.
authors.affiliation: Department of Integrative Biology, University of South Florida, Tampa, FL 33620 prevost@usf.edu.
authors.forename: Luanna B
authors.initials: LB
authors.lastname: Prevost
authors.affiliation: School of Biology and Ecology and Maine Center for Research in STEM Education, University of Maine-Orono, Orono, ME 04469.
authors.forename: Michelle K
authors.initials: MK
authors.lastname: Smith
authors.affiliation: Department of Molecular, Cellular, and Developmental Biology, University of Colorado Boulder, Boulder, CO 80309.
authors.forename: Jennifer K
authors.initials: JK
authors.lastname: Knight
mesh_terms: D018388:Codon, Terminator / Q000235:genetics*; D016001:Confidence Intervals; D003479:Curriculum; D003710:Demography; D004521:Educational Measurement; D005260:Female; D005823:Genetics / Q000193:education*; D006801:Humans; D016015:Logistic Models; D008297:Male; D017145:Models, Educational; D008957:Models, Genetic; D016017:Odds Ratio; D013334:Students / Q000523:psychology*; D013850:Thinking; D014956:Writing
chemical_list: D018388:Codon, Terminator