We describe a scheme for optimizing many-electron trial wave functions by minimizing the unreweighted variance of the energy using stochastic integration and correlated-sampling techniques. The scheme is restricted to parameters that are linear in the exponent of a Jastrow correlation factor, which are the most important parameters in the wave functions we use. The scheme is highly efficient an...

We simulate forecast errors with different variance-covariance structures based on macroeconomic data. The simulations are used to compare the performance of different forecast combining techniques.

We consider a random walk ( Z (1) n , · · · , Z n ) ∈ Z with the constraint that each coordinate of the walk is at distance one from the following one. In this paper, we show that this random walk is slowed down by a variance factor σ K = 2 K+2 with respect to the case of the classical simple random walk without constraint.

This paper first answers the question “why do the two most powerful techniques Dropout and Batch Normalization (BN) often lead to a worse performance when they are combined together?” in both theoretical and statistical aspects. Theoretically, we find that Dropout would shift the variance of a specific neural unit when we transfer the state of that network from train to test. However, BN would ...

Assessing the variability of an estimator is a key component of the process of statistical inference. In nonparametric regression, estimating observation-error variance is the principal ingredient needed to estimate the variance of the regression mean. Although there is an extensive literature on variance estimation in nonparametric regression, the techniques developed in conventional settings ...

As reflective practice has become an influential factor in teacher professional development, teachers need some techniques to enhance their reflective teaching. In this light, this study was intended to examine: (a) whether self-evaluation techniques could promote English as Foreign Language (EFL) teachers’ reflective teaching, (b) whether EFL teachers who used self-evaluation techniques would ...

This paper proposes and evaluates variance reduction techniques for efficient estimation of portfolio loss probabilities using Monte Carlo simulation. Precise estimation of loss probabilities is essential to calculating value-at-risk, which is simply a percentile of the loss distribution. The methods we develop build on delta-gamma approximations to changes in portfolio value. The simplest way ...

The external profile is among the first examined shape parameters of digital search trees in connection with the performance of unsuccessful search of a random query in the early 1970s. However, finer and important properties beyond the mean such as the variance and the limit law have remained unknown. In this extended abstract, we describe the first results for the asymptotic variance and the ...

Three methods are proposed to improve both population and individual inference within the nonlinear random coefficient regression framework by incorporating possible heterogeneity in the intraindividual variance structure. These methods extend existing variance function estimation techniques by pooling information across individuals. The methods are appropriate when it is reasonable to assume t...