Search results for "sampling"
showing 10 items of 788 documents
Sampling strategies and bias associated with the methods
2005
International audience
Extrapolation of the Species Accumulation Curve for Incomplete Species Samplings: A New Nonparametric Approach to Estimate the Degree of Sample Compl…
2015
9 pages; International audience; Incomplete species samplings are deemed to remain the common practice in those groups of animals, such as small or micro- invertebrates, with numerous species that often are more or less difficult to detect in the field. Thus, extrapolating the Species Accumulation Curve as far as possible beyond the actual sample size may thus serve as a useful (although imperfect) surrogate to the desired, but practically inaccessible, complete samplings. In this context, several kinds of theoretical or empirical models for the Species Accumulation Curve and also a lot of estimators of the asymptotic limit of the Curve (i.e. total species richness) have been proposed. The …
Tourism statistics and unobserved tourism: empirical evidences in Sicily
2013
Despite its strategic importance, accurately measuring visitor attendance has been a challenging and problematic exercise for tourism managers for decades. Consequently, the primary aim of tourism statistics of accurately quantify tourism flows has been only partially achieved; indeed at a lower territorial scale tourism statistics appear less precise and accurate. The aim of this paper is: to introduce the concept of unobserved tourism, by highlighting the main limits of official statistical systems (with a special focus on the European statistical system on tourism statistics; to formalize a theoretical model in which tourism nights and trips in a given destination are decomposed intoobse…
Tourism statistics and unobserved tourism: empirical evidences in Sicily
2013
Despite its strategic importance, accurately measuring visitor attendance has been a challenging and problematic exercise for tourism managers for decades. Consequently, the primary aim of tourism statistics of accurately quantify tourism flows has been only partially achieved; indeed at a lower territorial scale tourism statistics appear less precise and accurate. The aim of this paper is: to introduce the concept of unobserved tourism, by highlighting the main limits of official statistical systems (with a special focus on the European statistical system on tourism statistics; to formalize a theoretical model in which tourism nights and trips in a given destination are decomposed into obs…
Acceleration of the AChBP conformational transition using Temperarure Accelerated Molecular Dynamics
2013
Emotional and behavioral difficulties in adolescence: Relationship with emotional well-being, affect, and academic performance
2018
Abstract The main purpose of this study was to examine difficulties in behavioral and emotional adjustment and their relationship to subjective well-being, positive and negative affect, and academic performance in a representative sample of nonclinical adolescents. The sample consisted of a total of 1,664 participants (M = 16.12 years, SD = 1.36, range 14-19 years), selected through stratified cluster sampling. The instruments used were the Strengths and Difficulties Questionnaire (SDQ), the Positive and Negative Affect Schedule for Children (PANAS-C), the Personal Wellbeing Index-School Children (PWI-SC), the ad hoc academic performance questionnaire, and the Oviedo Scale of Response Infre…
Mediterranean Diet, Sustainability, and Tourism—A Study of the Market’s Demand and Knowledge
2023
Globalization intensified competitiveness among agribusinesses worldwide in recent years. The European Commission focused on enhancing sustainable agriculture and food products’ territorial uniqueness for competing in the international market. The Mediterranean diet (MD) is a model of feeding and lifestyle belonging to the ancient Mediterranean culture, which also embodies a sustainable food system. Therefore, in 2010, UNESCO recognized the MD as Intangible Cultural Heritage of Humanity, and Sicily (southern Italy) is its official physical site. Despite its worldwide fame, the notion of the MD runs the risk of being mystified because it is described most often as something that does not cor…
Browsing the information highway while driving: three in-vehicle touch screen scrolling methods and driver distraction
2012
Distraction effects of three alternative touch screen scrolling methods for searching music tracks on a mobile device were studied in a driving simulation experiment with 24 participants. Page-bypage scrolling methods with Buttons or Swipe that better facilitate resumption of visual search following interruptions were expected to lead to more consistent in-vehicle glance durations and thus, on less severe distraction effects than Kinetic scrolling. As predicted, Kinetic scrolling induced decreased visual sampling efficiency and increased visual load compared to Swipe, increased experienced workload compared to both Buttons and Swipe, as well as decreased lane keeping accuracy compared to ba…
Measuring Distraction at the Levels of Tactical and Strategic Control: The Limits of Capacity-Based Measures for Revealing Unsafe Visual Sampling Mod…
2011
The control theory of driving suggests that driver distraction can be analyzed as a breakdown of control at three levels. Common approach for analyzing distraction experimentally is to utilize capacity-based measures to assess distraction at the level of operational control. Three driving simulation experiments with 61 participants were organized to evaluate which kind of measures could be used to analyze drivers' tactical visual sampling models and the related effects of distraction while searching textual information on in-car display. The effects of two different text types were evaluated. The utilized capacity-based measures seemed to be insufficient for revealing participants' tactical…
Passive sampling in monitoring of nonylphenol ethoxylates and nonylphenol in aquatic environments
2012
The present practices for determining the concentration levels of various pollutants are in many respects insufficient and for this reason, there is an urgent need especially to develop more cost-effective sampling methods. In this study, a novel passive sampling tool (the Chemcatcher®) for monitoring nonylphenol ethoxylates (NPEOs) and nonylphenol (NP) in aqueous media was tested. These environmentally harmful substances have been widely used in different household and industrial applications and they affect aquatic ecosystems, for example, by acting as endocrine disrupting compounds. The highest accumulation of NPEOs and NP in laboratory-scale tests was obtained when using an SDB-XC (stan…