CEJOR manuscript No. (will be inserted by the editor) On relations between DEA-risk models and stochastic dominance efficiency tests Martin Branda · Miloˇ s Kopa Received: date / Accepted: date Abstract In this paper, several concepts of portfolio efficiency testing are com- pared, based either on Data Envelopment Analysis (DEA) or the second-order stochastic dominance (SSD) relation: constant return to scale (CRS) DEA mod- els, variable return to scale (VRS) DEA models, diversification-consistent (DC) DEA models, pairwise SSD efficiency tests, convex SSD efficiency tests and full SSD portfolio efficiency tests. Especially, the equivalence between VRS DEA model with binary weights and the SSD pairwise efficiency test is proved. DEA models equivalent to convex SSD efficiency tests and full SSD portfolio efficiency tests are also formulated. In the empirical application, the efficiency testing of 48 US rep- resentative industry portfolios using all considered DEA models and SSD tests is presented. The obtained efficiency sets are compared. A special attention is paid to the case of small number of the inputs and outputs. It is empirically shown that DEA models equivalent either to the convex SSD test or to the SSD portfo- lio efficiency test work well even with quite small number of inputs and outputs. However, the reduced VRS DEA model with binary weights is not able to identify all the pairwise SSD efficient portfolios. Keywords Data Envelopment Analysis · Second-order stochastic dominance · pairwise SSD efficiency · convex SSD efficiency · SSD portfolio efficiency Martin Branda Charles University in Prague, Faculty of Mathematics and Physics Department of Probability and Mathematical Statistics Sokolovsk´ a 83, Czech Republic Tel.: +420 221 913 404 E-mail: branda@karlin.mff.cuni.cz Miloˇ s Kopa Charles University in Prague, Faculty of Mathematics and Physics Department of Probability and Mathematical Statistics Sokolovsk´ a 83, Czech Republic