Is use of the general system justification scale across countries justified? Testing its measurement equivalence

System justification is a widely researched topic in social and political psychology. One major measurement instrument in system justification research is the General System Justification Scale (G-SJS). This scale has been used, among others, for comparisons across social groups in different countries. Such comparisons rely on the assumption that the scale is measurement equivalent. However, this assumption has never been comprehensively tested. Thus, the present two studies assessed the measurement equivalence of the G-SJS following classic measurement equivalence guidelines (i.e., multigroup confirmatory factor analyses) in Study 1 and using a new method for comparing larger numbers of groups in Study 2 (i.e., alignment optimization). In Study 1, we analysed the measurement equivalence in Great Britain (n = 444), Germany (n = 454), and France (n = 463). In Study 2, we used a publicly available dataset consisting of 66 samples from 30 countries (N = 13,495) to again assess the measurement equivalence of the scale. Results indicated (partial) metric equivalence, but not scalar equivalence in both studies. Overall, the studies indicate that mean comparisons across the examined countries are not warranted with the current form of the G-SJS. The scale needs to be revised for valid cross-country comparisons of means

JetStream : an open-source high-performance PCI express 3 streaming library for FPGA-to-host and FPGA-to-FPGA communication

Many FPGA-based accelerators are constrained by the available resources and multi-FPGA solutions can be necessary for building more capable systems. Available PCIe solutions provide only FPGA-to-Host communication. In this paper we present JetStream, an open-source1 modular PCIe 3 library, supporting not only fast FPGA-to-Host communication, but also allowing direct FPGA-to-FPGA communication which fully bypasses the memory subsystem. The direct mode saves memory bandwidth for multicast modes and permits to connect multiple FPGAs in various software defined topologies. We show the benefits of JetStream with a large FIR filter spanning four FPGA boards, achieving throughputs of up to 7.09 GB/s per link. Utilizing direct FPGA-to-FPGA transfers reduces the required memory bandwidth by up to 75%