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Researcher's Ability (researcher + ability)

Distribution by Scientific Domains

Life Sciences	50%

Selected Abstracts

An improved, simple nest-box trap

JOURNAL OF FIELD ORNITHOLOGY, Issue 1 2008
Scott L. Friedman
ABSTRACT The success of ornithological studies often hinges on a researcher's ability to capture individuals quickly and efficiently. Sometimes it is necessary to capture the same individual multiple times, as is the case in many metabolic, ecotoxicological, and immunocompetence studies. Several methods of capturing cavity-nesting birds at their nest boxes have been described. However, these methods proved inefficient when attempting to catch wary individuals that had already been captured previously. Here we describe a simple and inexpensive method for capturing cavity-nesting birds using a square plate of sheet metal (5.8 × 5.8 × 0.2 cm), a drinking straw, a piece of duct tape, and a monofilament line. This method has the advantages of allowing selective capture of one, but not both members of a pair and being nearly invisible to trap-shy birds. SINOPSIS El éxito de estudios ornitológicos está atado, muchas veces, a la habilidad del investigador para atrapar aves de forma rápida y eficiente. En ocasiones es necesario capturar el mismo individuo multiples veces, como es en el caso de estudios metabólicos, ecotoxicológicos o de inmunocompetencia. Se han descrito varios métodos para atrapar aves que anidan en cajas. Sin embargo, estos métodos han provado ser ineficientes cuando se intenta capturar aves que han sido alertadas por haberse capturado anteriormente. Describimos un método, simple y de bajo costo, para capturar aves que anidan en cajas, utilizando una plancha cuadrada de metal (5.8 × 5.8 × 0.2 cm), un sorbeto y un pedazo de cinta adhesiva plástica (duck tape) y un monofilamento. Este método tiene ventajas, y permite la captura selectiva de uno de los miembros de la pareja. El mismo es virtualmente invisible para las aves. [source]

Movement patterns and study area boundaries: influences on survival estimation in capture,mark,recapture studies

OIKOS, Issue 8 2008
Gregg E. Horton
The inability to account for the availability of individuals in the study area during capture,mark,recapture (CMR) studies and the resultant confounding of parameter estimates can make correct interpretation of CMR model parameter estimates difficult. Although important advances based on the Cormack,Jolly,Seber (CJS) model have resulted in estimators of true survival that work by unconfounding either death or recapture probability from availability for capture in the study area, these methods rely on the researcher's ability to select a method that is correctly matched to emigration patterns in the population. If incorrect assumptions regarding site fidelity (non-movement) are made, it may be difficult or impossible as well as costly to change the study design once the incorrect assumption is discovered. Subtleties in characteristics of movement (e.g. life history-dependent emigration, nomads vs territory holders) can lead to mixtures in the probability of being available for capture among members of the same population. The result of these mixtures may be only a partial unconfounding of emigration from other CMR model parameters. Biologically-based differences in individual movement can combine with constraints on study design to further complicate the problem. Because of the intricacies of movement and its interaction with other parameters in CMR models, quantification of and solutions to these problems are needed. Based on our work with stream-dwelling populations of Atlantic salmon Salmo salar, we used a simulation approach to evaluate existing CMR models under various mixtures of movement probabilities. The Barker joint data model provided unbiased estimates of true survival under all conditions tested. The CJS and robust design models provided similarly unbiased estimates of true survival but only when emigration information could be incorporated directly into individual encounter histories. For the robust design model, Markovian emigration (future availability for capture depends on an individual's current location) was a difficult emigration pattern to detect unless survival and especially recapture probability were high. Additionally, when local movement was high relative to study area boundaries and movement became more diffuse (e.g. a random walk), local movement and permanent emigration were difficult to distinguish and had consequences for correctly interpreting the survival parameter being estimated (apparent survival vs true survival). [source]

On Making Progress in Communication Science

HUMAN COMMUNICATION RESEARCH, Issue 4 2002
Franklin J. Boster
This essay advances practices for designing, analyzing, and reporting communication research. The arguments presented center around improving researchers' abilities to cumulate results across studies, but also apply to improving the utility of the individual study. Practices advocated include: (a) sophistication, falsification, and replication as important criteria for evaluating research design; (b) diminishing the importance of the null hypothesis statistical significance test, employing confidence intervals, and correcting correlations for both measurement error and range restriction when analyzing data; and (c) including both descriptive statistics and measures of the strength of bivariate relationships when reporting results. [source]

Independence and nonindependence: A simple method for comparing groups using multiple measures and the binomial test

EUROPEAN JOURNAL OF SOCIAL PSYCHOLOGY, Issue 2 2005
Craig McGarty
Existing methods for conducting analyses of small group data are either highly complicated or yield low power. Both of these limitations provide disincentives for the progress of research in this field. An alternative method modelled on the sign (binomial) test which involves comparing the differences of distributions based on multiple observations of each of the groups is presented. The calculations involved in the procedure are extremely simple. It is suggested that because the method enhances researchers' ability to make sound statistical inferences easily this should stimulate research on group-level processes and on social interaction more generally. Copyright © 2004 John Wiley & Sons, Ltd. [source]