Will I tell you that you are smart (dumb)? Deceiving Others about their IQ or about a Random Draw

2021 ◽  
Author(s):  
Giovanni Burro ◽  
Alessandro Castagnetti
Keyword(s):  
Random Draw

scholarly journals A New Upper Bound for Sampling Numbers

2021 ◽  
Author(s):  
Nicolas Nagel ◽  
Martin Schäfer ◽  
Tino Ullrich
Keyword(s):  
Upper Bound ◽  
Reproducing Kernel ◽  
Reproducing Kernel Hilbert Space ◽  
Sampling Procedure ◽  
Compact Embedding ◽  
Recovery Method ◽  
Grid Sampling ◽  
Integrable Functions ◽  
Random Draw ◽  
Square Integrable Functions

AbstractWe provide a new upper bound for sampling numbers $$(g_n)_{n\in \mathbb {N}}$$ ( g n ) n ∈ N associated with the compact embedding of a separable reproducing kernel Hilbert space into the space of square integrable functions. There are universal constants $$C,c>0$$ C , c > 0 (which are specified in the paper) such that $$\begin{aligned} g^2_n \le \frac{C\log (n)}{n}\sum \limits _{k\ge \lfloor cn \rfloor } \sigma _k^2,\quad n\ge 2, \end{aligned}$$ g n 2 ≤ C log ( n ) n ∑ k ≥ ⌊ c n ⌋ σ k 2 , n ≥ 2 , where $$(\sigma _k)_{k\in \mathbb {N}}$$ ( σ k ) k ∈ N is the sequence of singular numbers (approximation numbers) of the Hilbert–Schmidt embedding $$\mathrm {Id}:H(K) \rightarrow L_2(D,\varrho _D)$$ Id : H ( K ) → L 2 ( D , ϱ D ) . The algorithm which realizes the bound is a least squares algorithm based on a specific set of sampling nodes. These are constructed out of a random draw in combination with a down-sampling procedure coming from the celebrated proof of Weaver’s conjecture, which was shown to be equivalent to the Kadison–Singer problem. Our result is non-constructive since we only show the existence of a linear sampling operator realizing the above bound. The general result can for instance be applied to the well-known situation of $$H^s_{\text {mix}}(\mathbb {T}^d)$$ H mix s ( T d ) in $$L_2(\mathbb {T}^d)$$ L 2 ( T d ) with $$s>1/2$$ s > 1 / 2 . We obtain the asymptotic bound $$\begin{aligned} g_n \le C_{s,d}n^{-s}\log (n)^{(d-1)s+1/2}, \end{aligned}$$ g n ≤ C s , d n - s log ( n ) ( d - 1 ) s + 1 / 2 , which improves on very recent results by shortening the gap between upper and lower bound to $$\sqrt{\log (n)}$$ log ( n ) . The result implies that for dimensions $$d>2$$ d > 2 any sparse grid sampling recovery method does not perform asymptotically optimal.

A stochastic characterisation of the natural disturbance regime of the boreal mixedwood forest with implications for sustainable forest management

1999 ◽  
Vol 29 (4) ◽  
pp. 424-433 ◽  
Author(s):  
Glen W Armstrong
Keyword(s):  
Monte Carlo ◽  
Sustainable Forest Management ◽  
Natural Disturbance ◽  
Class Structure ◽  
Distribution Models ◽  
Age Class ◽  
Boreal Mixedwood Forest ◽  
Random Draw ◽  
Negative Exponential ◽  
Burn Rate

The annual area burned on an 8.6 × 106 ha study area in the boreal mixedwood forest of northeastern Alberta, Canada, was characterised as a serially independent random draw from a lognormal distribution. This characterisation was applied in Monte Carlo simulations, which showed that estimates of the mean annual burn rates, even with long sample periods, are highly imprecise. Monte Carlo simulation was also used to simulate the development of a forest subject to lognormally distributed annual burn rate in an attempt to characterise the equilibrium age-class structure. No equilibrium age-class structure could be identified from the simulation results. The validity of equilibrium age-class distribution models (e.g., the negative exponential and Weibull) and analysis that relies on these models is questioned for forests where the annual burn rate is highly variable.

scholarly journals Consulta de enfermagem no pré e pós-operatório de transplante renal: faz a diferença?

2009 ◽  
Vol 3 (2) ◽  
pp. 237
Author(s):  
Adriana Valongo Zani ◽  
Giovana Paz ◽  
Glaucimara Boniotti
Keyword(s):  
Renal Failure ◽  
Kidney Transplantation ◽  
Data Collection ◽  
Kidney Transplant ◽  
Professional Practice ◽  
Thematic Analysis ◽  
Descriptive Study ◽  
Qualitative Approach ◽  
Number Of Patients ◽  
Random Draw

ABSTRACTObjective: to describe the patient’s knowledge with chronic renal failure submitted to kidney transplantation on the importance of consultation with nursing for his treatment. Methodology: this is about an exploratory-descriptive study from qualitative approach. The data collection was from January to December 2007. The sample consisted of 36 patients undergoing kidney transplant from a total of 400. For the choice of the patients was a random draw simple daily. For data collection was used a questionnaire consisting of 11 questions concerning the information about the kidney transplant. For organization of the results was used thematic analysis proposed by Minayo. Results: as for nursing consultation for a significant number of patients claiming to be of importance to them, since they make them safer, take your questions and will be better targeted.  Conclusion: confirming the effectiveness of professional practice of nurses in the monitoring of renal patients who is subject to renal transplantation. Descriptors: nursing; kidney transplantation; chronic renal failure.RESUMOObjetivo: descrever o conhecimento do paciente portador de insuficiência renal crônica submetido a transplante renal referente à importância da consulta de enfermagem para seu tratamento. Metodologia: tratou-se de um estudo descritivo-exploratório com abordagem qualitativa. O período de coleta foi de janeiro a dezembro de 2007. A amostra foi constituída por 36 pacientes submetidos a transplante renal de um total de 400. Para a escolha dos pacientes foi realizado um sorteio aleatório simples diário. Para a coleta de dados foi utilizado um questionário composto por 11 perguntas referentes as informações sobre o transplante renal. Para organização dos resultados foi utilizada a análise temática proposta por Minayo. Resultados: quanto à consulta de enfermagem um número significativo de pacientes afirmam ser de importância aos mesmos, uma vez que os tornam mais seguros, tiram suas dúvidas e  serão melhor orientados. Conclusão: estes dados vêm a confirmar a eficácia da atuação profissional do enfermeiro no acompanhamento dos pacientes renais que se submeterão ao transplante renal. Descritores: enfermagem; transplante renal; insuficiência renal crônica.RESUMENObjetivo: describir el conocimiento del paciente portador de insuficiência renal crónica sometido a transplante renal, referente a la importáncia de la consulta de enfermería para su tratamiento. Metodologia: studio exploratório y descriptivo con abordaje cualitativa. El período de recogida fue de enero a diciembre de 2007. La muestra consistió de 36 pacientes sometidos a trasplante de riñón de un total de 400. Para la elección de los pacientes fue de un sorteo aleatorio simple diario. Para la recogida de datos se utilizó un cuestionario de 11 preguntas relativas a la información sobre el trasplante de riñón. Para la organización de los resultados se utilizó el análisis temático propuesto por Minayo. Resultados: cuanto a consulta de enfermeria, un número significativo de pacientes, afirma ser de importância a los mismos, una vez que los hacen mas seguros, disipan sus dudas y serán mejor orientados. Conclusión: lo que confirma la eficácia de la actuación profesional del enfermero, en el acompañamiento de los pacientes renales que se sometieron al transplante renal. Descriptores: enfermería; transplante renal; insuficiéncia renal crónica.

scholarly journals Effect of different Pilates workout endings on the kyphotic and lumbar lordotic angles

2021 ◽  
Vol 34 ◽  
Author(s):  
Jessica Marques da Silva ◽  
Josiele Folletto Bianchin ◽  
Emanuelle Francine Detogni Schmit ◽  
Cláudia Tarragô Candotti ◽  
Adriane Vieira
Keyword(s):  
Soft Tissue ◽  
Spinal Curvature ◽  
Significant Difference ◽  
Thoracic And Lumbar Spine ◽  
Before And After ◽  
Assessment Time ◽  
Pilates Method ◽  
Spine Curvature ◽  
Random Draw ◽  
Soft Tissue Mobilization

Abstract Introduction: There are no studies that investigate whether different workout endings of the Pilates method (PM), either prioritizing the activation of powerhouse muscles or the relaxation of muscles trained during the session, affects spinal curvature. Objective: Identify the immediate effect of a PM session that ends with soft tissue mobilization or wall exercises on the kyphotic and lumbar lordotic angles. Methods: A crossover clinical trial with 19 female Pilates practitioners that used a Flexicurve ruler to evaluate thoracic and lumbar spine curvature before and after a PM exercise protocol, and after endings that involved soft tissue mobilization using massage balls or wall exercises. The order of the different endings was chosen by random draw and the study volunteers participated in two interventions, with intervals of seven to ten days between them. Two two-way ANOVAs were performed (one for each postural variable), using the factors “assessment time” (pre-session; post-PE; post-ending) and “type of ending” (soft tissue or wall exercises). Results: There was no significant difference between the assessment times or endings for the kyphotic (p = 0.972; p = 0.747) and lumbar lordotic angles (p = 0.574; p = 0.627), respectively. Conclusion: Pilates instructors can opt for more relaxing or more active endings without affecting the kyphotic and lumbar lordotic angles.

scholarly journals Perceptions, Knowledge, and Practices Concerning Indoor Environmental Pollution of Parents or Future Parents

2020 ◽  
Vol 17 (20) ◽  
pp. 7669
Author(s):  
Laure Daniel ◽  
Marylou Michot ◽  
Maxime Esvan ◽  
Pauline Guérin ◽  
Guillaume Chauvet ◽  
...  
Keyword(s):  
Environmental Pollution ◽  
Social Inequalities ◽  
Knowledge Score ◽  
Cosmetic Products ◽  
Social Inequalities In Health ◽  
Indoor Pollutants ◽  
Factors Associated ◽  
Short And Long Term ◽  
Random Draw

Indoor pollutants can have short- and long-term health effects, especially if exposure occurs during prenatal life or early childhood. This study describe the perceptions, knowledge, and practices of adults concerning indoor environmental pollution. Adults of 18 to 45 years of age were recruited in the department of Ille-et-Vilaine (Brittany-France) in 2019 through a stratified random draw in the waiting rooms of general practitioners (GPs) (n = 554) who completed a self-questionnaire. The 71% who had already heard of this type of pollution were older (p = 0.001), predominantly women (p = 0.007), not expecting a baby (p = 0.005), and had a higher knowledge score (p < 0.001). The average knowledge score was 6.6 ± 6.6 out of 11, which was higher for participants living in a couple and with a higher level of education (p < 0.001). Some practices were well implemented (>80% of participants) (aeration during renovation) whereas others were insufficiently practiced (<60% of participants) (paying attention to the composition of cosmetic products). Factors associated differed depending on the frequency of integration: living in a couple and having a child for well implemented practices and educational level, knowledge level, and perception for those under implemented. Knowledge must be improved to modify perceptions and certain practices, making sure not to increase social inequalities in health.

scholarly journals Optical Energy Variability Induced by Speckle: The Cases of MERLIN and CHARM-F IPDA Lidar

Atmosphere ◽  
2019 ◽  
Vol 10 (9) ◽  
pp. 540 ◽  
Author(s):  
Cassé ◽  
Gibert ◽  
Edouart ◽  
Chomette ◽  
Crevoisier
Keyword(s):  
Optical Filter ◽  
Speckle Noise ◽  
Spectral Width ◽  
Atmospheric Methane ◽  
Energy Monitoring ◽  
Optical Energy ◽  
Performance Requirements ◽  
Signal Path ◽  
Random Draw

In the context of the FrenchGerman space lidar mission MERLIN (MEthane Remote LIdar missioN) dedicated to the determination of the atmospheric methane content, an end-to-end mission simulator is being developed. In order to check whether the instrument design meets the performance requirements, simulations have to count all the sources of noise on the measurements like the optical energy variability induced by speckle. Speckle is due to interference as the lidar beam is quasi monochromatic. Speckle contribution to the error budget has to be estimated but also simulated. In this paper, the speckle theory is revisited and applied to MERLIN lidar and also to the DLR (Deutsches Zentrum für Luft und Raumfahrt) demonstrator lidar CHARM-F. Results show: on the signal path, speckle noise depends mainly on the size of the illuminated area on ground; on the solar flux, speckle is fully negligible both because of the pixel size and the optical filter spectral width; on the energy monitoring path a decorrelation mechanism is needed to reduce speckle noise on averaged data. Speckle noises for MERLIN and CHARM-F can be simulated by Gaussian noises with only one random draw by shot separately for energy monitoring and signal paths.

Predator-prey ratios: a special case of a general pattern?

1992 ◽  
Vol 338 (1284) ◽  
pp. 113-130 ◽  
Keyword(s):  
General Pattern ◽  
Apparent Competition ◽  
Data Types ◽  
Predator Prey ◽  
Available Energy ◽  
Enemy Free Space ◽  
Energy Ratios ◽  
Community Data ◽  
Random Draw ◽  
Special Case

Approximately constant ratios between numbers of predator and non-predator (‘prey’) species have been observed in both community and food web data. However, only a limited set of explanations for the pattern have been considered, and interpretation is complicated by the non-equivalence of the two data types. Analysis of predator-prey ratios for a large and heterogeneous set of community data, drawn from freshwater, marine and terrestrial systems, shows that predator richness is almost, though not exactly, proportional to prey richness across and within habitats, with some suggestion that ratios differ between habitat types. Three existing, and two new, explanations for this result are considered: random draw (influence of the species pool); prey niches (more prey types provide more niches for predators); enemy-free space (the number of prey coexisting with a predator is limited by apparent competition); energy ratios (richness is proportional to available energy at each trophic level); and common determinants of diversity (factors influencing diversity act similarly on predators and prey). Separating these is not straightforward, but the latter two hypotheses have high generality, and component parts of each are supported by available evidence. We suggest that a hierarchy of processes, each of predominant importance at different scales from patches to regions, produces the observed pattern of predator-prey ratios and that, in view of these explanations, predator-prey ratios should be considered as a special case of the general problem of guild structure.

scholarly journals Optical Energy Variability Induced by Speckle: The Cases of MERLIN and CHARM-F IPDA Lidar

2019 ◽  
Author(s):  
Vincent Casse ◽  
Fabien Gibert ◽  
Dimitri Edouart ◽  
Olivier Chomette ◽  
Cyril Crevoisier
Keyword(s):  
Optical Filter ◽  
Speckle Noise ◽  
Spectral Width ◽  
Atmospheric Methane ◽  
Energy Monitoring ◽  
Optical Energy ◽  
Performance Requirements ◽  
Signal Path ◽  
Random Draw

In the context of the French-German space lidar mission MERLIN dedicated to the determination of the atmospheric methane content, an end-to-end mission simulator is being developed. In order to check whether the instrument design meets the performance requirements, simulations have to count all the sources of noise on the measurements like the optical energy variability induced by speckle. Speckle is due to interference as the lidar beam are quasi monochromatic. Speckle contribution to the error budget has to be estimated but also simulated. In this paper, the speckle theory is revisited and applied to MERLIN double pulsed IPDA lidar and also to the DLR demonstrator CHARM-F. Results show: on the signal path, speckle noise depends mainly on the size of the illuminating area on ground; on the solar flux, speckle is fully negligible both because the pixel size and the optical filter spectral width; on energy monitoring path a decorrelation mechanism is needed to reduce speckle noise on averaged data. Speckle noises for MERLIN and CHARM-F can be simulated by Gaussian noises with only one random draw by shot separately for energy monitoring and signal paths.

Breaking down the lithification bias: the effect of preferential sampling of larger specimens on the estimate of species richness, evenness, and average specimen size

Paleobiology ◽  
2018 ◽  
Vol 44 (2) ◽  
pp. 326-345 ◽  
Author(s):  
Andrew D. Hawkins ◽  
Michał Kowalewski ◽  
Shuhai Xiao
Keyword(s):  
Species Richness ◽  
Species Abundance ◽  
Specimen Size ◽  
Unconsolidated Sediments ◽  
Size Distributions ◽  
Analogue Model ◽  
Preferential Sampling ◽  
Significant Bias ◽  
Random Draw ◽  
Taphonomic Processes

AbstractLithification, the transition of unconsolidated sediments to fully indurated rocks, can potentially bias estimates of species richness, evenness, and body size distribution derived from fossil assemblages. Fossil collections made from well-indurated rocks consistently exhibit lower species richness, lower evenness, and larger average specimen size relative to collections made from unconsolidated sediments, even when collections are drawn from the same assemblage. This phenomenon is known as “lithification bias.” While the bias itself has been demonstrated empirically, much less attention has been paid to its causes. Proposed causes include taphonomic processes (e.g., destruction of small specimens during early diagenesis) and methodological differences (e.g., sieving vs. counting specimens on outcrops, bedding surfaces, or mechanically split surfaces). Here we investigate the potential effects of preferential intersection that could also result in a methodologically related bias: the preferential sampling of larger specimens relative to smaller ones when fossils are counted on rock surfaces. We used an analogue model to simulate preferential intersection (fossil collection via splitting fossiliferous rocks) and compare the results with a random-draw model that approximates the effects of sieving. The model was parameterized using nine different combinations of species abundance and species size distributions. The results show that, with rare exceptions, species richness is 5–23% lower, evenness 5–25% lower, and average specimen size 24–150% larger in preferential-intersection than in random-draw simulations. We conclude that preferential intersection can impose a significant bias independent of other mechanisms (e.g., preferential destruction of smaller specimens during diagenetic or sampling processes), that the magnitude of this bias is partially dependent on the species abundance and size distributions, and that this bias alone does not fully account for empirically observed lithification bias on species richness (i.e., other sources of bias are also at work).

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