Research-based assessment of students' beliefs about experimental physics: When is gender a factor?

The existence of gender differences in student performance on conceptual assessments and their responses to attitudinal assessments has been repeatedly demonstrated. This difference is often present in students' preinstruction responses and persists in their postinstruction responses. However, one area in which the presence of gender differences has not been extensively explored is undergraduate laboratory courses. For example, one of the few laboratory focused research-based assessments, the Colorado Learning Attitudes about Science Survey for Experimental Physics (E-CLASS), has not been tested for the existence of gender differences in students' responses. Here, we utilize a national data set of responses to the E-CLASS to determine if they demonstrate significant gender differences. We also investigate how these differences vary along multiple student and course demographic slices, including course level (first-year vs.\ beyond-first-year) and major (physics vs.\ non-physics). We observe a gender gap in pre- and postinstruction E-CLASS scores in the aggregate data both for the overall score and for most items individually. However, for some subpopulations (e.g., beyond-first-year students) the size or even existence of the gender gap depends on another dimension (e.g., student major). We also find that for all groups the gap in postinstruction scores vanishes or is greatly reduced when controlling for preinstruction scores, course level, and student major.Comment: 11 pages, 3 figures, accepted to Phys. Rev. - PE

Improvement or selection? A longitudinal analysis of students' views about experimental physics in their lab courses

Laboratory courses represent a unique and potentially important component of the undergraduate physics curriculum, which can be designed to allow students to authentically engage with the process of experimental physics. Among other possible benefits, participation in these courses throughout the undergraduate physics curriculum presents an opportunity to develop students' understanding of the nature and importance of experimental physics within the discipline as a whole. Here, we present and compare both a longitudinal and pseudo-longitudinal analysis of students' responses to a research-based assessment targeting students' views about experimental physics -- the Colorado Learning Attitudes about Science Survey for Experimental Physics (E-CLASS) -- across multiple, required lab courses at a single institution. We find that, while pseudo-longitudinal averages showed increases in students' E-CLASS scores in each consecutive course, analysis of longitudinal data indicates that this increase was not driven by a cumulative impact of laboratory instruction. Rather, the increase was driven by a selection effect in which students who persisted into higher-level lab courses already had more expert-like beliefs, attitudes, and expectations than their peers when they started the lower-level courses.Comment: 6 pages, 1 figure, submitted as a short paper to Phys. Rev. PE

Students' epistemologies about experimental physics: Validating the Colorado Learning Attitudes about Science Survey for Experimental Physics

Student learning in instructional physics labs represents a growing area of research that includes investigations of students' beliefs and expectations about the nature of experimental physics. To directly probe students' epistemologies about experimental physics and support broader lab transformation efforts at the University of Colorado Boulder (CU) and elsewhere, we developed the Colorado Learning Attitudes about Science Survey for Experimental Physics (E-CLASS). Previous work with this assessment has included establishing the accuracy and clarity of the instrument through student interviews and preliminary testing. Several years of data collection at multiple institutions has resulted in a growing national data set of student responses. Here, we report on results of the analysis of these data to investigate the statistical validity and reliability of the E-CLASS as a measure of students' epistemologies for a broad student population. We find that the E-CLASS demonstrates an acceptable level of both validity and reliability on measures of, item and test discrimination, test-retest reliability, partial-sample reliability, internal consistency, concurrent validity, and convergent validity. We also examine students' responses using Principal Component Analysis and find that, as expected, the E-CLASS does not exhibit strong factors.Comment: 10 pages, 4 figures, 7 tables, submitted to Phys. Rev. ST - PE

Students' views about the nature of experimental physics

The physics community explores and explains the physical world through a blend of theoretical and experimental studies. The future of physics as a discipline depends on training of students in both the theoretical and experimental aspects of the field. However, while student learning within lecture courses has been the subject of extensive research, lab courses remain relatively under-studied. In particular, there is little, if any, data available that addresses the effectiveness of physics lab courses at encouraging students to recognize the nature and importance of experimental physics within the discipline as a whole. To address this gap, we present the first large-scale, national study ($N_{institutions}=75$ and $N_{students}=7167$) of undergraduate physics lab courses through analysis of students' responses to a research-validated assessment designed to investigate students' beliefs about the nature of experimental physics. We find that students often enter and leave physics lab courses with ideas about experimental physics as practiced in their courses that are inconsistent with the views of practicing experimental physicists, and this trend holds at both the introductory and upper-division levels. Despite this inconsistency, we find that both introductory and upper-division students are able to accurately predict the expert-like response even in cases where their views about experimentation in their lab courses disagree. These finding have implications for the recruitment, retention, and adequate preparation of students in physics.Comment: 10 pages, 2 figures, Accepted to Phys. Rev. PE

Lab notebooks as scientific communication: investigating development from undergraduate courses to graduate research

In experimental physics, lab notebooks play an essential role in the research process. For all of the ubiquity of lab notebooks, little formal attention has been paid to addressing what is considered `best practice' for scientific documentation and how researchers come to learn these practices in experimental physics. Using interviews with practicing researchers, namely physics graduate students, we explore the different experiences researchers had in learning how to effectively use a notebook for scientific documentation. We find that very few of those interviewed thought that their undergraduate lab classes successfully taught them the benefit of maintaining a lab notebook. Most described training in lab notebook use as either ineffective or outright missing from their undergraduate lab course experience. Furthermore, a large majority of those interviewed explained that they did not receive any formal training in maintaining a lab notebook during their graduate school experience and received little to no feedback from their advisors on these records. Many of the interviewees describe learning the purpose of, and how to maintain, these kinds of lab records only after having a period of trial and error, having already started doing research in their graduate program. Despite the central role of scientific documentation in the research enterprise, these physics graduate students did not gain skills in documentation through formal instruction, but rather through informal hands-on practice.Comment: 10 page