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Many anonymous communication networks (ACNs) with different privacy goals have been developed. However, there are no accepted formal definitions of privacy and ACNs often define their goals and adversary models ad hoc. However, for the understanding and comparison of different flavors of privacy, a common foundation is needed. In this paper, we introduce an analysis framework for ACNs that captures the notions and assumptions known from different analysis frameworks. Therefore, we formalize privacy goals as notions and identify their building blocks. For any pair of notions we prove whether one is strictly stronger, and, if so, which. Hence, we are able to present a complete hierarchy. Further, we show how to add practical assumptions, e.g. regarding the protocol model or user corruption as options to our notions. This way, we capture the notions and assumptions of, to the best of our knowledge, all existing analytical frameworks for ACNs and are able to revise inconsistencies between them. Thus, our new framework builds a common ground and allows for sharper analysis, since new combinations of assumptions are possible and the relations between the notions are known.

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Relevance and backgroundEmpirical research on teachers' professional knowledge and skills is becoming increasingly important for practice in teacher education and especially in vocational education and training (De Wever et al. 2016). Several debates on educational policies have ensued, and discourse on this topic has featured political catchphrases such as 'outcome orientation' (Cochran-Smith et al. 2012; European Commission 2007). The central theme of the discussion on outcome orientation is that both the educational system and teaching can Abstract Background: Research on teachers' professional knowledge and skills is becoming increasingly important. However, valid assessments of teachers' knowledge and skills are scarce. In this study, we report on our development and validation (following the international Standards for Educational and Psychological Testing) of a situation-based tool to assess pre-service and in-service teachers' pedagogical content knowledge (PCK) of business and economics in vocational education and training. Methods:We present a conceptual model and empirical evidence indicating the validity of test content and internal structure of the new developed assessment. We conducted conceptual analyses, interviews and standardized ratings with experts, and piloted the tool with 338 pre-service and in-service teachers. Results:Our results indicate that our assessment tool is valid and reliable to measure case-related PCK (a central component of situation-oriented knowledge) of pre-service and in-service teachers. Conclusions:A video-and performance-based assessment tool for assessing the strategic component of PCK is developed and currently being validated. Together, these tools can serve to assess the professional knowledge and skills of business and economics teachers.

Background Key elements of instructional quality include the teacher's ability to immediately react in domain‐specific classroom situations. Such skills – defined as action‐related skills – can only be validly assessed using authentic representations of real‐life teaching practice. However, research has not yet explained how teachers apply domain‐specific knowledge for teaching and to what extent action‐related skills are transferable from one domain to another. Aims Our study aims to examine (1) the relationship between action‐related skills, content knowledge, and pedagogical content knowledge, and (2) the domain specificity of action‐related skills of (prospective) teachers in the two domains of mathematics and economics. Sample(s) We examined German pre‐service and in‐service teachers of mathematics (N = 239) and economics (N = 321), including n = 96 (prospective) teachers who teach both subjects. Methods Action‐related skills in mathematics and economics were measured using video‐based performance assessments. Content knowledge and pedagogical content knowledge were assessed using established paper–pencil tests. Correlation analyses, linear regressions, and a path model were applied. Results In mathematics and economics, we find a similar pattern of moderate correlations between action‐related skills, content knowledge, and pedagogical content knowledge. Moreover, a significant correlation between action‐related skills in mathematics and economics can be explained almost entirely by underlying relations between content knowledge and pedagogical content knowledge in both domains. Conclusions Our findings suggest that action‐related skills empirically differ from domain‐specific knowledge and should be considered as domain‐specific constructs. This indicates that teacher education should not only focus on domain‐specific teacher knowledge, but may also provide learning opportunities for action‐related skills in each domain.