Megan McOsker

Date of Award


Level of Access Assigned by Author

Campus-Only Thesis

Degree Name

Master of Science (MS)




Sara Lindsay

Second Committee Member

John R. Thompson

Third Committee Member

Robert Franzosa


This study is an investigation of student ideas about error and variability in the context of interpreting graphs from primary science literature. I describe overall graph comprehension difficulties and how students interpret representations of variability and error. A set of questions was asked of undergraduate marine science majors as they interpreted a graph from a peer-reviewed marine science publication. Their responses were examined for evidence of the types of difficulties they encountered and for evidence of their underlying conceptual understandings of error and variability. The students reported a number of difficulties in interpreting graphs. These self-reported difficulties included problems understanding unfamiliar structural elements of the graph such as error bars. Students also reported difficulties resulting from unfamiliarity with domain-specific background knowledge or content. Results indicate that students hold alternate conceptions of the significance and meaning of error and variability. The ideas that error represents some kind of mistake or inaccuracy and that variability is by itself a threat to the validity of the results were relatively widespread. These ideas about error and variability indicate a relatively unsophisticated understanding of scientific process. Given these alternate conceptions, and the students' reported difficulties in graph comprehension, instructional implications are discussed.