Nonverbal communicative signals modulate attention to object properties

We investigated whether the social context in which an object is experienced influences the encoding of its various properties. We hypothesized that when an object is observed in a communicative context, its intrinsic features (such as its shape) would be preferentially encoded at the expense of its extrinsic properties (such as its location). In 3 experiments, participants were presented with brief movies, in which an actor either performed a noncommunicative action toward 1 of 5 different meaningless objects, or communicatively pointed at 1 of them. A subsequent static image, in which either the location or the identity of an object changed, tested participants’ attention to these 2 kinds of information. Throughout the 3 experiments we found that communicative cues tended to facilitate identity change detection and to impede location change detection, whereas in the noncommunicative contexts we did not find such a bidirectional effect of cueing. The results also revealed that the effect of the communicative context was a result the presence of ostensive-communicative signals before the object-directed action, and not to the pointing gesture per se. We propose that such an attentional bias forms an inherent part of human communication, and function to facilitate social learning by communication. (PsycINFO Database Record (c) 2014 APA, all rights reserved

Trade Less and Exit Overcrowded Markets

We study active investment skills in relation to returns to scale in the active mutual fund industry. Using a sample of 13,807 funds from 16 domicile countries investing in 42 equity markets from 2001 to 2014, we find that they achieve negative trading performance on average, driven mainly by particularly low returns to their trades in U.S. equities. Exploring their investment environment, we find convincing evidence of decreasing returns to scale around the world, especially for the U.S. market. Based on theory of optimal fund size, we estimate the optimal size of the active mutual fund industry. We find that the active mutual fund industry in the U.S. has exceeded the optimal level, whereas in international markets, there may still be room for expan- sion. Consistent with this view, we find that mutual fund managers have been gradually reallocating their assets away from the U.S. and more into international equity markets

Information content when mutual funds deviate from benchmarks

__Abstract__ The consensus wisdom of active mutual fund managers, as reflected in their average over-and underweighting decisions, contains valuable information about future stock returns. Analyzing a comprehensive sample of active U.S. equity funds from 1984 to 2008, we find that stocks heavily overweighted by active funds outperform their underweighted counterparts by more than 7% per year, after adjustments for their loadings on the market, size, value, and momentum factors. This large premium dissipates quickly as the consensus view becomes publicly available. These results are consistent with the notion that informed investing by active mutual funds enhances the informativeness of stock prices. In addition, active mutual funds invest only a small portion of fund assets in high alpha stocks, in accordance with the consensus view that active mutual funds on average fail to outperform passive benchmarks. Data, as supplemental material, are available at http://dx.doi.org/10.1287/mnsc.2013.1847

Impact of the South Asian monsoon outflow on atmospheric hydroperoxides in the upper troposphere

During the OMO (Oxidation Mechanism Observation) mission, trace gas measurements were performed on board the HALO (High Altitude Long Range) research aircraft in summer 2015 in order to investigate the outflow of the South Asian summer monsoon and its influence on the composition of the Asian monsoon anticyclone (AMA) in the upper troposphere over the eastern Mediterranean and the Arabian Peninsula. This study focuses on in situ observations of hydrogen peroxide (H$_{2}$O$_{2}$$^{obs}$) and organic hydroperoxides (ROOH$^{obs}$) as well as their precursors and loss processes. Observations are compared to photostationary-state (PSS) calculations of H$_{2}$O$_{2}$$^{PSS}$ and extended by a separation of ROOH$^{obs}$ into methyl hydroperoxide (MHP$^{PSS}$) and inferred unidentified hydroperoxide (UHP$^{PSS}$) mixing ratios using PSS calculations. Measurements are also contrasted to simulations with the general circulation ECHAM–MESSy for Atmospheric Chemistry (EMAC) model. We observed enhanced mixing ratios of H$_{2}$O$_{2}$$^{obs}$ (45 %), MHP$^{PSS}$ (9 %), and UHPPSS (136 %) in the AMA relative to the northern hemispheric background. Highest concentrations for H$_{2}$O$_{2}$$^{obs}$ and MHP$^{PSS}$ of 211 and 152 ppb$_{V}$, respectively, were found in the tropics outside the AMA, while for UHP$^{PSS}$, with 208 ppt$_{V}$, highest concentrations were found within the AMA. In general, the observed concentrations are higher than steady-state calculations and EMAC simulations by a factor of 3 and 2, respectively. Especially in the AMA, EMAC underestimates the H$_{2}$O$_{2}$$^{EMAC}$ (medians: 71 ppt$_{V}$ vs. 164 ppt$_{V}$) and ROOHEMAC (medians: 25 ppt$_{V}$ vs. 278 ppt$_{V}$) mixing ratios. Longitudinal gradients indicate a pool of hydroperoxides towards the center of the AMA, most likely associated with upwind convection over India. This indicates main contributions of atmospheric transport to the local budgets of hydroperoxides along the flight track, explaining strong deviations from steady-state calculations which only account for local photochemistry. Underestimation of H$_{2}$O$_{2}$$^{EMAC}$ by approximately a factor of 2 in the Northern Hemisphere (NH) and the AMA and overestimation in the Southern Hemisphere (SH; factor 1.3) are most likely due to uncertainties in the scavenging efficiencies for individual hydroperoxides in deep convective transport to the upper troposphere, corroborated by a sensitivity study. It seems that the observed excess UHPPSS is excess MHP transported to the west from an upper tropospheric source related to convection in the summer monsoon over Southeast Asia

Modification of a conventional photolytic converter for improving aircraft measurements of NO2_{2} via chemiluminescence

Nitrogen oxides (NO$_{x}$≡NO+NO$_{2}$) are centrally involved in the photochemical processes taking place in the Earth\u27s atmosphere. Measurements of NO$_{2}$, particularly in remote areas where concentrations are of the order of parts per trillion by volume (pptv), are still a challenge and subject to extensive research. In this study, we present NO$_{2}$ measurements via photolysis–chemiluminescence during the research aircraft campaign CAFE Africa (Chemistry of the Atmosphere – Field Experiment in Africa) 2018 around Cabo Verde and the results of laboratory experiments to characterize the photolytic converter used. We find the NO$_{2}$ reservoir species MPN (methyl peroxy nitrate) to produce the only relevant thermal interference in the converter under the operating conditions during CAFE Africa. We identify a memory effect within the conventional photolytic converter (type 1) associated with high NO concentrations and rapidly changing water vapor concentrations, accompanying changes in altitude during aircraft measurements, which is due to the porous structure of the converter material. As a result, NO$_{2}$ artifacts, which are amplified by low conversion efficiencies, and a varying instrumental background adversely affect the NO$_{2}$ measurements. We test and characterize an alternative photolytic converter (type 2) made from quartz glass, which improves the reliability of NO$_{2}$ measurements in laboratory and field studies

Measurement report: Hydrogen peroxide in the upper tropical troposphere over the Atlantic Ocean and western Africa during the CAFE-Africa aircraft campaign

This study focuses on the distribution of hydrogen peroxide (H2O2) in the upper tropical troposphere at altitudes between 8 and 15 km based on in situ observations during the Chemistry of the Atmosphere: Field Experiment in Africa (CAFE-Africa) campaign conducted in August–September 2018 over the tropical Atlantic Ocean and western Africa. The measured hydrogen peroxide mixing ratios in the upper troposphere show no clear trend in the latitudinal distribution with locally increased levels (up to 1 ppbv​​​​​​​) within the Intertropical Convergence Zone (ITCZ), over the African coastal area, as well as during measurements performed in proximity to the tropical storm Florence (later developing into a hurricane). The observed H2O2 distribution suggests that mixing ratios in the upper troposphere seem to be far less dependent on latitude than assumed previously and the corresponding factors influencing the photochemical production and loss of H2O2. The observed levels of H2O2 in the upper troposphere indicate the influence of convective transport processes on the distribution of the species not only in the tropical but also in the subtropical regions. The measurements are compared to observation-based photostationary steady-state (PSS) calculations and numerical simulations by the global ECHAM/MESSy Atmospheric Chemistry (EMAC) model. North of the ITCZ, PSS calculations produce mostly lower H2O2 mixing ratios relative to the observations. The observed mixing ratios tend to exceed the PSS calculations by up to a factor of 2. With the exception of local events, the comparison between the calculated PSS values and the observations indicates enhanced H2O2 mixing ratios relative to the expectations based on PSS calculations in the north of the ITCZ. On the other hand, PSS calculations tend to overestimate the H2O2 mixing ratios in most of the sampled area in the south of the ITCZ by a factor of up to 3. The significant influence of convection in the ITCZ and the enhanced presence of clouds towards the Southern Hemisphere indicate contributions of atmospheric transport and cloud scavenging in the sampled region. Simulations performed by the EMAC model also overestimate hydrogen peroxide levels particularly in the Southern Hemisphere, most likely due to underestimated cloud scavenging. EMAC simulations and PSS calculations both indicate a latitudinal gradient from the Equator towards the subtropics. In contrast, the measurements show no clear gradient with latitude in the mixing ratios of H2O2 in the upper troposphere with a slight decrease from the ITCZ towards the subtropics, indicating a relatively low dependency on the solar radiation intensity and the corresponding photolytic activity. The largest model deviations relative to the observations correspond with the underestimated hydrogen peroxide loss due to enhanced cloud presence, scavenging, and rainout in the ITCZ and towards the south.</p

African Linguistics in Central and Eastern Europe, and in the Nordic Countries

Non peer reviewe