Scenarios can be defined as alternative versions of the same dataset, with the same variables but different observations and/or values. Applied scientists frequently want to predict how much good an intervention will do, by comparing outcomes from the same model betwen different scenarios. Alternatively, they may want to compare outcomes between different models applied to the same scenario, as...

Variances involved in estimating the abundance of the nitrogen-fixing marine cyanobacterium, Trichodesmium Ehrenberg, were evaluated by repeated sampling using bottle casts and plankton net tows at two stations in the southern East China Sea. The variance among individual samples and the variance arising from subsampling processes were separated by the method of analysis of variance, and the co...

traditional survey methods may cause refusals to respond or untruthful replies when encounter the sensitive questions. the randomized response technique (rrt) is designed to decrease social desirability bias and obtain reliable estimates. this study aimed to apply these new methods on the sensitive questions survey.simmons model was applied in the survey of issues relevant to commercial sex amo...

Correct ranking of animals in across-country genetic evaluation requires careful design of both, the model for breeding value estimation and the adjustment for heterogeneous variance. The Nordic across-country genetic evaluation for yield traits of Danish, Finnish and Swedish red dairy cattle is based on a multiple-trait random regression test-day model, which considers observations from differ...

This is where is the estimated posteriori probability that xj belongs to term i, is the estimated mixing coefficient, is the estimated mean, and is the estimated variance of the ith term. We have written our estimate as to explicitly draw attention to the dependence of it on the estimated parameter set . The reader is referred to the works of McLachlan, G.J., and Basford, K.E. (1988) and Titf̂ x...

Traditional portfolio optimization has often been criticized for not taking estimation risk into account. Estimation risk is mainly driven by the parameter uncertainty regarding the expected asset returns rather than their variances and covariances. The global minimum variance portfolio has been advocated by many authors as an appropriate alternative to the classical mean-variance optimal portf...

BACKGROUND It has been speculated on theoretical grounds that biomarkers are superior surrogates for chemical exposures to air samples in epidemiology studies. METHODS AND RESULTS Biomarkers were classified according to their position in the exposure-disease continuum-that is, parent compound, reactive intermediate, stable metabolite, macromolecular adduct, or measure of cellular damage. Beca...

The simplest and most natural vol-of-vol estimator, the pre-estimated spot variance-based realized variance, is typically plagued by a large finite-sample bias. In this paper, we analytically show that allowing for overlap of consecutive local windows to pre-estimate variance may correct particular, provide feasible rule bias-optimal selection length when volatility CKLS process. effectiveness ...

genetic trend for production traits were estimated in iranian holstein cattle using the first lactation data recorded by cattle breeding and dairy product improvement center of the state from 1991 to 2006. effect of some factors on genetic trend was investigated using data from 18 large herds. (co) variance components and genetic parameters were estimated, using five trait animal model and em-a...

Animal traits differ not only in mean, but also in variation around the mean. For instance, one sire’s daughter group may be very homogeneous, while another sire’s daughters are much more heterogeneous in performance. The difference in residual variance can partially be explained by genetic differences. Models for such genetic heterogeneity of environmental variance include genetic effects for ...