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This paper investigates why subjects in laboratory experiments on quantity precommitment games consistently choose capacities above the Cournot level - the subgame-perfect equilibrium. We argue that this puzzling regularity may be attributed to players’ perceptions of their opponents’ skill or level of rationality. We first show theoretically that it is the case by modelling a two-stage game of capacity investment and pricing with bounded rational players. We then design an experiment in which we use the level of experience as a proxy for the level of rationality and match subjects with different levels of experience. We find significant differences in behavior depending on opponents’ experience; moreover, players facing inexperienced players tend to choose higher capacities than they would otherwise.

To evaluate importance of bacterioplankton in the Barents Sea, we investigated the spatial and temporal distribution of bacterial abundance, biomass and production in relation to spring-bloom stages. During three cruises in 2003–2005, 12 stations were investigated. Average bacterial abundance (±S.D.) in the photic zone was 3.6±3.0×105 cells ml−1, corresponding to 7.1±6.1 mg C m−3. Bacterial production in the photic zone was measured using dual labelling technique with 3H-thymidine and 14C-leucine, resulting in average production rates (±S.D.) of 1.5±1.0 and 6.9±4.8 mg C m−3 d−1, respectively. In spite of low water temperature, the bacterial community was well developed and active. Similarity analysis of stations resulted in four distinct spring-bloom stages, covering pre- early-, late- and post-bloom stages. In the photic zone, bacterial biomass on average corresponded to 6±2% of phytoplankton biomass. Highest integrated bacterial biomass was observed at mid- to late-bloom stages. Average bacterial production equalled 32±6% (±S.E., n=24) of particulate primary production. The bacterial production to primary production ratio tended to increase at late-bloom stages. The observed bacterial activity illustrates the importance of the bacterial pathway for channelling carbon from DOC through the microbial food web back into the classical food web, which previously has not been adequately considered in plankton ecosystem models of the Barents Sea.

Bacteria in the Arctic Waters are well adapted to low temperatures and play a key role in the transformation of organic matter. However, the activity of planktonic bacteria at cellular level remains poorly understood. In this study, we use fluorescent markers (4′,6′-diamidino-2-phenylindole (DAPI), 5-cyano-2,3-ditolyl tetrazolium chloride (CTC), Live/Dead BacLight viability kit) to discriminate between bacterial cells with a variety of physiological activities in the 0–200 m water column and sinking particles. During two field studies (July 2003 and 2004), we covered nine stations in the northern Barents Sea. The median bacterial abundance (DAPI staining) in the upper 50 m layer was 0.9×106 cells ml−1 (range 0.2–3.2×106 cells ml−1) in 2003 and 0.5×106 cells ml−1 (range 0.2–1.0×106 cells ml−1) in 2004. Bacteria with sufficient electron transport activity to be stained with CTC were on average 10% of the total count and ca. 20% of the total cells had intact cell membranes. In the water column, proxies of substrate availability (POC, PON, chlorophyll a, primary production) and bacterial production (thymidine and leucine uptake) correlated strongly with total bacterial count, CTC-stained cells and cells with ‘leaky’ membrane (stained with propidium iodine), but not with the concentration of cells with intact cell membrane. Contrary to expectations, the proportion of CTC-stained bacteria was not higher in the sinking particles (captured with sediment traps) compared to the ambient water. However, out of the bacteria with intact cell membranes, a higher proportion scored as CTC positive in the aggregates compared to the ambient water. Bacterial cells with ‘leaky’ cell membranes formed the largest part of total cell count in all samples, and accumulated in sites with high microbial activity (sinking aggregates, chlorophyll maxima, layers of high primary and bacterial production). We hypothesize that the source of the bacterial cells with ‘leaky’ cell membranes was metabolically the most active fraction of the bacterial assemblage (stained with CTC).

The paper presents the results of an economic experiment in which the effects of fees on allocative efficiency of tradable utilization permits (e.g. pollution permits) are explored. Laboratory subjects (university students) play the roles of firms whose generic product requires a specific input or permits. Scarcity is exogenously introduced by a fixed supply of tradable production permits. Three treatments are compared: No fee imposed (N); a fixed tax per permit (T); and partial retraction of permits and subsequent redistribution by auction (A). Treatments T and A represent two different ways of imposing fees, which are designed to be revenue equivalent. Our results indicate that, after controlling for deviation of permit prices from a prediction based on fundamentals, fees have an impact on distribution of permits. Interestingly, a fixed tax enhances efficiency compared to the case of no fees while retraction and reallocation by auction tends to reduce efficiency. Apparently, subjects’ decision making is affected by the imposition of fees, but how and to what extent depends on the method used.