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Previous research on student thinking about experimental measurement and uncertainty has primarily focused on students’ procedural reasoning: Given some data, what should students calculate or do next? This approach, however, cannot tell us what beliefs or conceptual understanding leads to students’ procedural decisions. To explore this relationship, we first need to understand the range of students’ beliefs and conceptual understanding of measurement. In this work, we explored students’ philosophical beliefs about the existence of a true value in experimental measurement. We distributed a survey to students from 12 universities in which we presented two viewpoints on the existence of a true definite position resulting from an experiment, asking participants to indicate which view they agreed with more and asking them to explain their choice. We found that participants, both students and experts, varied in their beliefs about the existence of a true definite position and discussed a range of concepts related to quantum mechanics and the experimental process to explain their answers, regardless of whether or not they agreed with the existence of a true value. From these results, we postulate that students who exhibit similar procedural reasoning may hold widely varying philosophical views about measurement. We recommend that future work investigates this potential relationship and whether and how instruction should attend to these philosophical views in addition to students’ procedural decisions. 

Measurement uncertainty is an important topic in the undergraduate laboratory curriculum. Previous research on student thinking about experimental measurement uncertainty has focused primarily on introductory-level students’ procedural reasoning about data collection and interpretation. In this paper, we extended this prior work to study upper-level students’ thinking about sources of measurement uncertainty across experimental contexts, with a particular focus on classical and quantum mechanics contexts. We developed a survey to probe students’ thinking in the generic question “What comes to mind when you think about measurement uncertainty in [classical/quantum] mechanics?” as well as in a range of specific experimental scenarios and interpreted student responses through the lens of availability and accessibility of knowledge pieces. We found that limitations of the experimental setup were most accessible to students in classical mechanics while principles of the underlying physics theory were most accessible to students in quantum mechanics, even in a context in which this theory was not relevant. We recommend that future research probe which sources of uncertainty experts believe are relevant in which contexts and how instruction in both classical and quantum contexts can help students draw on appropriate sources of uncertainty in classical and quantum experiments. 

Uncertainty is an important concept in physics laboratory instruction. However, little work has examined how students reason about uncertainty beyond the introductory (intro) level. In this work we aimed to compare intro and beyond-intro students’ ideas about uncertainty. We administered a survey to students at 10 different universities with questions probing procedural reasoning about measurement, student-identified sources of uncertainty, and predictive reasoning about data distributions. We found that intro and beyond-intro students answered similarly on questions where intro students already exhibited expert-level reasoning, such as in comparing two data sets with the same mean but different spreads, identifying limitations in an experimental setup, and predicting how a data distribution would change if more data were collected. For other questions, beyond-intro students generally exhibited more expertlike reasoning than intro students, such as when determining whether two sets of data agree, identifying principles of measurement that contribute to spread, and predicting how a data distribution would change if better data were collected. Neither differences in institutions, student majors, lab courses taken, nor research experience were able to fully explain the variability between intro and beyond-intro student responses. These results call for further research to better understand how students’ ideas about uncertainty develop beyond the intro level. 

Numerous studies have identified gender inequity in how students divide roles in lab courses. Few studies, however, have probed how these inequities impact women's experimental physics identity development. In this work, we used closed-response surveys to investigate which lab tasks students view as part of "doing physics" and how these designations varied by gender. In both courses, we found that most students viewed working with the experimental apparatus, taking lab notes, doing data analysis, and thinking about the physics theory behind the experiment as part of doing physics. Only 50% of students, however, viewed managing the group progress as part of doing physics. While men and women's views did not vary in the first-semester lab course, in the third-semester course women were more likely to view notes and managing as part of doing physics than were men. Given that previous research has indicated that women are more likely to take on managing and note-taking roles than men, our results suggest that women may be receiving less recognition as physicists from their peers, which may hinder their experimental physics identity development. 

While understanding laboratory equipment is an important learning goal of physics laboratory (lab) instruction, previous studies have found inequities as to who gets to use equipment in in-person lab classes. With the transition to remote learning during the COVID-19 pandemic, class dynamics changed and the effects on equipment usage remain unclear. As part of a larger effort to make intro physics labs more equitable, we investigated student equipment usage based on gender and race in two introductory physics lab courses, one taught in-person and one taught remotely. We found inequities between men and women for in-person instruction, replicating previous work with a new student population. In contrast, we found that remote instruction created a more gender equitable learning environment, albeit with one student typically in charge of the equipment per class session. When we looked at equipment handling based on student race, we found no inequities in either format. These results suggest that changes should be made in introductory labs to create a more gender equitable learning environment and that some aspects of remote labs could help make these labs more equitable.