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Student reports are a common approach to characterizing how students experience their classrooms. We used a recently developed method-multilevel confirmatory factor analysis-to determine whether commonly employed measures of achievement goal structure constructs (mastery and performance) typically verified at the student level can be verified at the classroom level as well, using a sample of 1,406 7th-and 1,822 8th-grade students in 188 mathematics classrooms. Nine multilevel confirmatory factor analyses were examined: (a) modeling each classroom goal structure dimension separately (mastery, performance-approach, performance-avoidance, combined performance), (b) 4 models allowing 2 latent factors to covary (mastery ϩ performance-approach, mastery ϩ performance-avoidance, performance-approach ϩ performance-avoidance, mastery ϩ combined performance), and (c) a model reflecting the trichotomous goals framework (mastery ϩ performance-approach ϩ performanceavoidance). Consistent with prior research, the theorized models of classroom goal structure adequately represented students within the same classroom at Level 1. Although all models were acceptable at the individual level, only the performance-avoidance model represented the expected goal structure at the classroom level. Future research and replication are necessary to examine whether self-reports of classroom goal structure, and by implication other measures of classroom climate, reflect an individuallevel phenomenon rather than a classroom-level construct, which has important theoretical and applied implications.

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Massive Open Online Courses (MOOCs) have the potential to democratize education by providing learners with access to high-quality free online courses. However, evidence supporting this democratization across countries is limited. We explored the question of MOOC democratization by conducting cross-national comparisons of gender differences in the enrollment in and completion of science, technology, engineering, and mathematics (STEM) MOOCs. We found that while females were less likely than males to enroll in STEM MOOCs, they were equally likely to complete them. Further, a higher probability to enroll in STEM MOOCs and smaller gender gaps in STEM MOOC enrollment and completion were found in less gender-equal and less economically developed countries.

A novel concept of stereoscopic imaging providing a depth-of-field blur effect close to that experienced in natural vision is presented. With this concept, only a mini-volume of the reproduced three-dimensional space is displayed in full spatial resolution. This volume is centered around the current point of fixation of the viewer. In an exploratory study the concept of a so-called "depth of-interest" (DOI) display was evaluated. Subjects assessed computer-generated 3D images with different depth-selective filtering characteristics (i.e., varying in-depth extents of the mini-volume with full resolution). Results indicate that the DOI display can indeed improve 3D viewing comfort. Apparently, a somewhat smaller depth of field than experienced in natural vision is preferred in stereoscopic image representations