BACKGROUND Conventional mixed models for the analysis of diet diary data have introduced several simplifying assumptions, such as that of a single standard deviation for within-person day-to-day variation which is common to all individuals. OBJECTIVE We developed a model in which the within-person standard deviation was allowed to differ from person to person. DESIGN The model was demonstra...

This paper provides two approaches to estimate the standard deviation of measurements from baseline noise in instrumental output when (i) in theory, the noise can be approximated by a well-established random process in statistics and mathematics, referred to as a stationary process and (ii) in practice, the baseline noise is the predominant source of measurement error. For the first approach pr...

Scaling invariance of time series has been making great contributions in diverse research fields. But how to evaluate scaling exponent from a real-world series is still an open problem. Finite length of time series may induce unacceptable fluctuation and bias to statistical quantities and consequent invalidation of currently used standard methods. In this paper a new concept called correlation-...

This article assesses the impact of pulmonary resection on quality of life by means of a systematic quantitative review of the available literature. Perioperative changes in quality of life scales were measured by the Cohen's effect size method (mean change of the variable divided by its baseline standard deviation). After lobectomy, most quality-of-life scales differed slightly from preoperati...

This paper reports on the analysis of a 2.5 year-long time series of ASAR wide swath mode (WSM) observations for characterizing the soil moisture dynamics. The employed ASAR WSM data set consists of 152 VV-polarized scenes acquired in the period between April 2005 and September 2007 over the Naqu river basin located on the Tibetan Plateau. For four different spatial domains, with areas of 30x30...

In this paper, a Bayesian approach is developed for simultaneously comparing multiple experimental treatments with a common control treatment in an exploratory clinical trial. The sample size is set to ensure that, at the end of the study, there will be at least one treatment for which the investigators have a strong belief that it is better than control, or else they have a strong belief that ...

OBJECTIVE To determine medical students' self awareness and ability to discriminate right from left; to identify characteristics associated with this ability; and to identify any techniques used to aid discrimination. DESIGN Questionnaire and psychometric study. SETTING Undergraduate medical school, Northern Ireland. PARTICIPANTS 290 first year undergraduate students. MAIN OUTCOME MEASU...

This cross-sectional study evaluated the intrasession reliability and concurrent validity of trunk accelerometry (with force plate measurements) for vertical ground reaction force and external mechanical power recorded during a standardized heel-rise (HR) test in 54 elderly subjects (mean +/- standard deviation age 81.2 +/- 6.4 yr).Peak force as well as peak and average power revealed intraclas...

Simple motor reaction time to, visual stimuli in dependence of stimulus intensity was measured and the histograms representing the distribution of reaction time were constructed. It was found that the reaction time distributions are positively skewed for all stimulus intensities used. The mean value, the standard deviation as well as the coefficient of skewness increases as the stimulus intensi...

The reported resolution of timing the moment of impact in fast human movements differs widely depending on the task. Surprisingly, better timing is reported for the demanding task of batting a ball than for the much simpler task of tapping in synchrony with two hands. We wondered whether this is because a sizeable part of timing variability arises from misjudging the distance in the direction o...