Detecting periodicity in experimental data using linear modeling techniques

Fourier spectral estimates and, to a lesser extent, the autocorrelation function are the primary tools to detect periodicities in experimental data in the physical and biological sciences. We propose a new method which is more reliable than traditional techniques, and is able to make clear identification of periodic behavior when traditional techniques do not. This technique is based on an information theoretic reduction of linear (autoregressive) models so that only the essential features of an autoregressive model are retained. These models we call reduced autoregressive models (RARM). The essential features of reduced autoregressive models include any periodicity present in the data. We provide theoretical and numerical evidence from both experimental and artificial data, to demonstrate that this technique will reliably detect periodicities if and only if they are present in the data. There are strong information theoretic arguments to support the statement that RARM detects periodicities if they are present. Surrogate data techniques are used to ensure the converse. Furthermore, our calculations demonstrate that RARM is more robust, more accurate, and more sensitive, than traditional spectral techniques.Comment: 10 pages (revtex) and 6 figures. To appear in Phys Rev E. Modified styl

Scholarly communication in transition: The use of question marks in the titles of scientific articles in medicine, life sciences and physics 1966–2005

The titles of scientific articles have a special significance. We examined nearly 20 million scientific articles and recorded the development of articles with a question mark at the end of their titles over the last 40 years. Our study was confined to the disciplines of physics, life sciences and medicine, where we found a significant increase from 50% to more than 200% in the number of articles with question-mark titles. We looked at the principle functions and structure of the titles of scientific papers, and we assume that marketing aspects are one of the decisive factors behind the growing usage of question-mark titles in scientific articles

Sibling interaction as a facilitator for talent development in sport

While current research has begun to address parental influences on talent development in sport, sibling interaction remains relatively under-examined. Therefore, this study aimed to explore the underpinning mechanisms through which sibling interaction impacts on talent development. Retrospective phenomenological interviews were conducted with four sets of siblings (N = 9), where at least one sibling had competed to an elite level. Findings revealed several higher-order themes that impacted positively on the talented athletes’ development: regularity of interaction in sport, emotional interpersonal skills, rivalry, resilience, co-operation and separation. Separation appeared as the athlete reached elite status, suggesting that these former mechanisms primarily impact during the development phase. Such findings support and extend the sibling, elite sport and talent development literature and provide valuable insight for both practitioners and academics. Importantly, coaches should consider a sibling’s role as an important mechanism outside of the formal coaching structure for talent development

Developmental experiences of elite female youth soccer players

To advance the literature on talent development within elite female athletes, this study investigated the developmental experiences of elite youth female soccer players. We adopted an interpretive approach where four players (M age = 16.75) were initially interviewed to gain a retrospective understanding of their development as soccer players. Subsequent fieldwork and further interviews were used to gain a current and prospective understanding of their development as players. Data were subjected to an inductive analysis, composite sequence analysis and a collaborative member checking process to co-construct a sequential, developmental understanding of the players' experiences within elite youth soccer. The findings suggested that the soccer experience of fathers and/or older brothers played a significant role in the players' development. Soccer fathers were able to provide advice and guidance specific to the needs of their daughter-player at different age ranges whilst at the same time reinforcing the importance of coach–player relationships. Soccer brothers acted as either positive or negative models for their sister-players and served as a source of information about key career choices. Friends inside (termed as soccer friends) and outside (termed as non-soccer friends) soccer played a significant role in helping players to lead the disciplined lifestyle required of an elite youth soccer player. Finally, findings suggest that self-regulation and adaptive volitional behaviours appear to be key intra-individual factors associated with talent development in female soccer. These findings are considered in the light of previous talent development literature alongside directions for future research

The value of applying commercial fishers' experience to designed surveys for identifying characteristics of essential fish habitat for adult summer flounder

Identifying the habitat requirements of marine fish is necessary to conserve and manage their populations, but these requirements are poorly understood for many species. One method of screening for important habitat characteristics is to identify differences in habitat features between areas of high and low fish abundance. We tested the association between abundance of adult summer flounder Paralichthys dentatus and benthic habitat features at two study areas in the Middle Atlantic Bight in summer 2004. The study included trawl and remote-sensing surveys that were designed and conducted with the assistance of commercial fishers. Within each area, a local commercial fisher designated specific locations a priori as productive or unproductive for fishing. Summer flounder abundance, as measured by mean catch per area swept, was significantly greater at sites designated as productive than at sites designated as unproductive (6.5 times greater in Maryland and 4.7 times greater in Rhode Island). These results indicate that summer flounder were attracted consistently to localized habitats that must have had different characteristics than other nearby locations. Habitat variables associated with the substrate (e.g., particle size, bottom shape, and presence of sessile organisms) were measured along trawl paths using underwater video imagery. The measured variables did not explain abundance well, suggesting that microscale characteristics of the substrate did not affect summer flounder distribution. Summer flounder were most abundant at depths of 10-20 m; however, both high and low catch rates occurred in this depth range, indicating that other factors also were important. These results suggest that additional localized variables merit further investigation to determine their importance to summer flounder. This study demonstrates the importance of combining fishers' knowledge and experience with planned surveys to identify essential habitat features for fish