Sample size effects

Statistical analysis of fetal and neonatal data should be conducted with careful consideration of study design, the endpoint under consideration, sample size, effects of gender, and the influence of litter on analytical outcome. It is critical that litter-mates not be treated as independent observations in the statistical analysis (13). 

Explosion Retardation. The sample-size effects of the explosion retardation of mercury and silver oxalates and fulminates are discussed... 

For simulation of a bulk liquid, the use of periodic boundary conditions is common in order to reduce finite sample size effects. This subjea is well covered by Allen and Tildesley," and most of their discussion also applies to chemically reacting systems. Boundary conditions can be cubic, or to reduce directional effects, truncated octahedron symmetry can be used, thereby giving a more spherical unit cell. 

Method to remove sample size effect Development of an universal calibration... 

Following measurement the data must be analysed to take into account the corrections needed for sample size effects (multiple scattering) and resolution broadening, in the case of cross-section measurements. At this stage theory is used. For example, resonance region data are analysed using a standard resonance formalism to obtain the parameters. 

Koch, C.F. (1987) Prediction of sample size effects on the measmed temporal and geographic distribution patterns of species. Paleobiology, 13 100-107. 

The sizes were determined by transmission EM on thin samples. Size effects on the electronic specific heat were studied [12]. Compare also comments on this latter measurement in two reviews [13, 14]. 

Powell, R.C. (1970) Thermal and sample-size effects on the fluorescence lifetime and energy transfer in tetracene-doped anthracene. Phys. Rev. B2, 2090. 

Even though there are no apparent sample size effects on the MIP pore size distributions in the above example, it is important to keep the same sample characteristics (amount and number of pieces) in order to improve the overall reproducibility of results. As an example. Figure 9.8 shows cumulative pore volumes and first derivatives of two MIP experiments repeated with the same sample characteristics and the same measuring procedure. This highlights the good repeatability of MIP results when similar experimental conditions are carefully maintained. 

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