Anne Chao proposed a very popular, nonparametric estimator of the species richness of a community, on the basis of a limited size sampling of this community. This expression was originally derived on a statistical basis as a lower-bound estimate of the number of missing species in the sample and provides accordingly a minimal threshold for the estimation of the total species richness of the com...

We examined time-dependent statistical properties of electromyographic (EMG) signals recorded from intrinsic hand muscles during handwriting. Our analysis showed that trial-to-trial neuronal variability of EMG signals is well described by the lognormal distribution clearly distinguished from the Gaussian (normal) distribution. This finding indicates that EMG formation cannot be described by a c...

We analyze a sample of bright long bursts and find that the pulses duration have a lognormal distribution while the intervals between pulses have an excess of long intervals (relative to lognormal distribution). This excess can be explained by the existence of quiescent times, long periods with no signal above the background. The lognormal distribution of the intervals (excluding the quiescent ...

We introduce a quantile-based multivariate log-normal distribution, providing new skewed distribution with positive support. The parameters of this are interpretable in terms quantiles marginal distributions and associations between pairs variables, desirable feature for statistical modeling purposes. derive properties the involving transformations, closed-form expressions mixed moments, expect...

a simple but novel and applicable approach is proposed to solve the problem of smoothing effect of ordinary kriging estimate which is widely used in mining and earth sciences. it is based on transformation equation in which z scores are derived from ordinary kriging estimates and then rescaled by the standard deviation of sample data and the sample mean is added to the result. it bears the grea...

Total of 260 soil profiles were reported to investigate the arsenic spatial distribution and vertical variation in Guangdong province. The arsenic concentration followed an approximately lognormal distribution. The arsenic geometric mean concentration of 10.4 mg/kg is higher than that of China. An upper baseline concentration of 23.4 mg/kg was estimated for surface soils. The influence of soil ...

BACKGROUND When outcomes are binary, the c-statistic (equivalent to the area under the Receiver Operating Characteristic curve) is a standard measure of the predictive accuracy of a logistic regression model. METHODS An analytical expression was derived under the assumption that a continuous explanatory variable follows a normal distribution in those with and without the condition. We then co...

In the literature, contradictory results have been published regarding the form of the limiting (long-time) grain size distribution (LGSD) that characterizes the late stage grain coarsening in two-dimensional and quasi-two-dimensional polycrystalline systems. While experiments and the phase-field crystal (PFC) model (a simple dynamical density functional theory) indicate a log-normal distributi...

We show that according to the GRB internal shock model the pulse duration and the interval between neighboring pulses are correlated and have a similar distribution. We analyze a sample of bright long bursts and find that the pulses duration have a lognormal distribution while the intervals has an excess of long intervals (relative to lognormal distribution). This excess can be explained by the...

Radio propagation measurement is carried out in Jakarta, Indonesia, in anticipation of digital TV implementation in the country. Measurements are made using a fixed, portable receiver outdoors and indoors. Spatial variations of the received power, both large-scale and small-scale, are measured in these locations. Results show that the largescale path loss variation characteristics, as described...