MISSPECIFICATION IN SIMULTANEOUS SYSTEMS: AN ALTERNATIVE TEST AND ITS APPLICATION TO A MODEL OF THE SHRIMP MARKET

Concern over the effects of public policies based on misspecified econometric models motivates interest in a procedure to test, diagnose, and improve the specification of models that have been estimated with three-stage least squares. A test of system-wide specification based on Hausman's specification test is employed in a test of the a priori restrictions placed on the parameters of a structural model of the U.S. shrimp market. The null hypothesis of proper specification is rejected. After diagnosis via a comparison of unrestricted and restricted reduced forms and respecification, the null hypothesis cannot be rejected.Research Methods/ Statistical Methods,

Remote fieldwork: using portable wireless networks and backhaul links to participate remotely in fieldwork

Fieldwork is an important means of contextualising knowledge and developing subject-specific and generic transferable skills. However, field locations are not always accessible. To address this problem we present a remote fieldwork approach that makes use of a portable wireless network and other mobile technologies to support fieldwork at a distance. As well as improving access to fieldwork, this approach can also be used to provide communication tools to fieldworkers, enabling them to share their findings and talk to their colleagues while in the field. This paper presents the portable communications toolkit we have developed and reports on three recent trials

Hemispheric specialization in selective attention and short-term memory: a fine-coarse model of left- and right-ear disadvantages.

Serial short-term memory is impaired by irrelevant sound, particularly when the sound changes acoustically. This acoustic effect is larger when the sound is presented to the left compared to the right ear (a left-ear disadvantage). Serial memory appears relatively insensitive to distraction from the semantic properties of a background sound. In contrast, short-term free recall of semantic-category exemplars is impaired by the semantic properties of background speech and is relatively insensitive to the sound’s acoustic properties. This semantic effect is larger when the sound is presented to the right compared to the left ear (a right-ear disadvantage). In this paper, we outline a speculative neurocognitive fine-coarse model of these hemispheric differences in relation to short-term memory and selective attention, and explicate empirical directions in which this model can be critically evaluated

Thyroid hormones correlate with field metabolic rate in ponies, Equus ferus caballus

Acknowledgments The authors thank Jürgen Dörl for technical help and for taking care of the animals and Peter Thompson for technical assistance with the doubly labelled water analysis. Funding The study was supported by a grant from the German Research Foundation (DFG;GE 704/13-1).Peer reviewedPublisher PD

Biologists meet statisticians: A workshop for young scientists to foster interdisciplinary team work

Life science and statistics have necessarily become essential partners. The need to plan complex, structured experiments, involving elaborated designs, and the need to analyse datasets in the era of systems biology and high throughput technologies has to build upon professional statistical expertise. On the other hand, conducting such analyses and also developing improved or new methods, also for novel kinds of data, has to build upon solid biological understanding and practise. However, the meeting of scientists of both fields is often hampered by a variety of communicative hurdles - which are based on field-specific working languages and cultural differences. As a step towards a better mutual understanding, we developed a workshop concept bringing together young experimental biologists and statisticians, to work as pairs and learn to value each others competences and practise interdisciplinary communication in a casual atmosphere. The first implementation of our concept was a cooperation of the German Region of the International Biometrical Society and the Leibnitz Institute DSMZ-German Collection of Microorganisms and Cell Cultures (short: DSMZ), Braunschweig, Germany. We collected feedback in form of three questionnaires, oral comments, and gathered experiences for the improvement of this concept. The long-term challenge for both disciplines is the establishment of systematic schedules and strategic partnerships which use the proposed workshop concept to foster mutual understanding, to seed the necessary interdisciplinary cooperation network, and to start training the indispensable communication skills at the earliest possible phase of education

Long-Period Giant Companions to Three Compact, Multiplanet Systems

Understanding the relationship between long-period giant planets and multiple smaller short-period planets is critical for formulating a complete picture of planet formation. This work characterizes three such systems. We present Kepler-65, a system with an eccentric (e = 0.28 ± 0.07) giant planet companion discovered via radial velocities (RVs) exterior to a compact, multiply transiting system of sub-Neptune planets. We also use precision RVs to improve mass and radius constraints on two other systems with similar architectures, Kepler-25 and Kepler-68. In Kepler-68 we propose a second exterior giant planet candidate. Finally, we consider the implications of these systems for planet formation models, particularly that the moderate eccentricity in Kepler-65\u27s exterior giant planet did not disrupt its inner system

Seasonal changes in energy expenditure, body temperature and activity patterns in llamas (Lama glama)

The authors thank Knut Salzmann und Arne Oppermann for technical help and for taking care of the animals and Anna Stölzl for help with the administering of the ruminal unit of the telemetry system. The study was supported by a grant from the German Research Foundation (DFG) to A.R. (RI 1796/3-1).Peer reviewedPublisher PD

Adding a reward increases the reinforcing value of fruit

Adolescents' snack choices could be altered by increasing the reinforcing value (RV) of healthy snacks compared with unhealthy snacks. This study assessed whether the RV of fruit increased by linking it to a reward and if this increased RV was comparable with the RV of unhealthy snacks alone. Moderation effects of sex, hunger, BMI z-scores and sensitivity to reward were also explored. The RV of snacks was assessed in a sample of 165 adolescents (15.1 (SD 1.5) years, 39.4% boys and 17.4% overweight) using a computerised food reinforcement task. Adolescents obtained points for snacks through mouse clicks (responses) following progressive ratio schedules of increasing response requirements. Participants were (computer) randomised to three experimental groups (1: 1: 1): fruit (n 53), fruit + reward (n 60) or unhealthy snacks (n 69). The RV was evaluated as total number of responses and breakpoint (schedule of terminating food reinforcement task). Multilevel regression analyses (total number of responses) and Cox's proportional hazard regression models (breakpoint) were used. The total number of responses made were not different between fruit + reward and fruit (b -473; 95% CI -1152, 205, P=0.17) or unhealthy snacks (b 410; 95% CI -222, 1043, P = 0.20). The breakpoint was slightly higher for fruit than fruit + reward (HR 1.34; 95% CI 1.00, 1.79, P=0.050), whereas no difference between unhealthy snacks and fruit + reward (HR 0.86; 95% CI 0.62, 1.18, P=0.34) was observed. No indication of moderation was found. Offering rewards slightly increases the RV of fruit and may be a promising strategy to increase healthy food choices. Future studies should however, explore if other rewards, could reach larger effect sizes