NMR measurements on core samples saturated with brine returns valuable information on the porous structure of the rock core. Monitoring a single fluid component in a relaxation experiment reflects the pore size distribution and thus the degree of sorting of the porous rock. The basic assumptions are that the mobility of the component confined in the porous rock is of such a value that a small f...

Although interspecific body size frequency distributions are well documented for many taxa, including the insects, intraspecific body size frequency distributions (IaBSFDs) are more poorly known, and their variation among mass-based and linear estimates of size has not been widely explored. Here we provide IaBSFDs for 16 species of insects based on both mass and linear estimates and large sampl...

All too frequently, a software cost estimate is required in the early stages of the life-cycle when requirements and design specifications are immature. To produce a cost estimate under these conditions requires extensive use of expert judgment and addressing significant estimation uncertainty. Research has shown that expert judgment under the right conditions can yield relatively "accurate" es...

A statistical model developed from scientific theory may “fail to fit” the available data if the scientific theory is incorrect or if the sample size is too small. The former point is obvious but the latter is more subtle. In the latter case, the hypothesized model may fail to fit in the sense that it is viewed as unnecessarily complicated, and so the investigators settle upon a simpler model t...

Holling suggested that discontinuities in the body size distributions among species of animals are a universal feature of terrestrial biomes. We compared the magnitudes of body size gaps of mammal communities of North America and Australia to those generated by a simple random null model. In most biomes, no gaps were significantly larger than random, so discontinuities in body size distribution...

We review the accumulated knowledge on city size distributions and determinants of urban growth. This topic is of interest because of a number of key stylized facts, including notably Zipf’s law for cities (which states that the number of cities of size greater than S is proportional to 1/S) and the importance of urban primacy. We first review the empirical evidence on the upper tail of city si...

BACKGROUND Sample size calculations should correspond to the intended method of analysis. Nevertheless, for non-normal distributions, they are often done on the basis of normal approximations, even when the data are to be analysed using generalized linear models (GLMs). METHODS For the case of comparison of two means, we use GLM theory to derive sample size formulae, with particular cases bei...

Harvey, R. J. (University of California, Davis), and Allen G. Marr. Measurement of size distributions of bacterial cells. J. Bacteriol. 92:805-811. 1966.-Apparatus for the automatic determination of the volume distribution of particles by measurement of the amplitude of pulses generated in a Coulter transducer is described. Distributions of volume estimated by direct measurement of pulse amplit...

Simplified representation of atmospheric aerosol size distributions using absolute principal component analysis T. W. Chan and M. Mozurkewich Department of Chemistry and Centre for Atmospheric Chemistry, York University, Toronto, Ontario, Canada now at: Environment Canada, Toronto, Ontario, Canada Received: 15 August 2006 – Accepted: 2 October 2006 – Published: 18 October 2006 Correspondence to...