*39%*:**Student difficulties with quantum states while translating state vectors in Dirac notation to wave functions in position and momentum representations***37%*:**Development, validation and in-class evaluation of a sequence of clicker questions on Larmor precession of spin in quantum mechanics***35%*:**Approaches to data analysis of multiple-choice questions***34%*:**Design and validation of the Quantum Mechanics Conceptual Survey***31%*:**Item response theory analysis of the mechanics baseline test***30%*:**Validation and administration of a conceptual survey on the formalism and postulates of quantum mechanics***29%*:**Is the Force Concept Inventory Biased? Investigating Differential Item Functioning on a Test of Conceptual Learning in Physics***29%*:**Testing the development of student conceptual and visualization understanding in quantum mechanics through the undergraduate career***27%*:**Improving Students' Understanding of Quantum Mechanics***27%*:**Surveying students' understanding of quantum mechanics in one spatial dimension***26%*:**Criteria for collapsing rating scale responses: A case study of the CLASS***26%*:**Conceptual Survey of Electricity and Magnetism: Analysis of the items and recommendations for improvement***26%*:**Energy measurement resources in spins-first and position-first quantum mechanics***25%*:**Exploratory factor analysis of a Force Concept Inventory data set***25%*:**Student use of a material anchor for quantum wave functions***25%*:**What can normalized gain reveal about individual learning on the FCI?***25%*:**Identifying characteristics of pairs of questions that students answer similarly***25%*:**Multidimensional Item Response Theory and the Conceptual Survey of Electricity and Magnetism***25%*:**Assessing the assessment: Mutual information between response choices and factor scores**