Effects of low sample mean values and small sample size on the estimation of the fixed dispersion parameter of Poisson-gamma models for modeling motor vehicle …

D Lord, LF Miranda-Moreno - Safety Science, 2008 - Elsevier
… , where the treatment of prior knowledge may have a large effect on the outcome of the … the
effects of small sample and low sample mean values on the posterior value of the dispersion

… vehicle crashes using Poisson-gamma models: Examining the effects of low sample mean values and small sample size on the estimation of the fixed dispersion …

D Lord - Accident Analysis & Prevention, 2006 - Elsevier
… shown that small sample sizes and low sample mean values can significantly and negatively
affect different estimators of the dispersion parameter. The dispersion parameter becomes …

Effects of sample size on the performance of species distribution models

MS Wisz, RJ Hijmans, J Li, AT Peterson… - Diversity and …, 2008 - Wiley Online Library
… overlap values thus ranged from 0 to 1 with smaller values … To examine the ecological effects
of extremes in dispersal … as a function of the main fixed effects: sample size (10, 30, or 100 …

Adjustment for maximum likelihood estimate of negative binomial dispersion parameter

BJ Park, D Lord - Transportation Research Record, 2008 - journals.sagepub.com
… characterized by small sample size and low sample mean values (5… adjusted inverse dispersion
parameters to examine this effect (… on the Estimation of the Fixed Dispersion Parameter. …

Maximum likelihood estimation of the negative binomial dispersion parameter for highly overdispersed data, with applications to infectious diseases

JO Lloyd-Smith - PloS one, 2007 - journals.plos.org
… can be overlooked with some fixed probability p z , while all … to higher sample mean m̂ and
lower sample variance ŝ 2 … can have disproportionate effect on the sample mean. For m = …

Effects of sample size on bender-based axial G0 measurements

M Arroyo, D Muir Wood, PD Greening, L Medina… - …, 2006 - icevirtuallibrary.com
… of their average value. This was equivalent to a 100% uncertainty in modulus determination.
… end—that is, where the bender element is placed—the nodes are fixed. At the upper end, …

Lower bounds on sample size in structural equation modeling

JC Westland - Electronic commerce research and applications, 2010 - Elsevier
… detect a minimum correlation (effect) δ in estimating k latent (… | = 0.37 still has a great deal of
dispersion, and we might find it … that z-values are adequate approximations for t-values in the …

Simple sample size calculation for cluster-randomized trials.

RJ Hayes, S Bennett - International journal of epidemiology, 1999 - academic.oup.com
… of interest, and the size of the effect to be detected, cluster … dispersion resulting from variation
in true cluster rates. … years are fixed, equation (2) can be rearranged to derive an estimate of …

Dispersion Statistics and Sample Size Estimates for Three Fish Species (Symphodus ocellatus, Serranus scriba and Diplodus annularis) in the Lavezzi Islands …

D Mouillot, JM Culioli, A Lepretre… - Marine Ecology, 1999 - Wiley Online Library
… predicted valuesample variance "s1# on the log09 of the sample mean "x¹#[ An ordinary
least square regression is used in this study\ which di}ers somewhat from the geometric mean

Investigating the effects of the fixed and varying dispersion parameters of Poisson-gamma models on empirical Bayes estimates

D Lord, PYJ Park - Accident Analysis & Prevention, 2008 - Elsevier
… The results of the study show that the selection of the functional form of NB models has
an important effect on EB estimates both in terms of estimated values, weight factors, and …