Mothers are expected to use environmental cues to modify maternal investment to optimize their fitness. However, when the environment varies unpredictably, cues may not be an accurate proxy of future conditions. Under such circumstances, selection favors a diversifying maternal investment strategy. While there is evidence that the environment is becoming more uncertain, the extent to which moth...

We propose a generic framework based on a new stochastic variance-reduced gradient descent algorithm for accelerating nonconvex low-rank matrix recovery. Starting from an appropriate initial estimator, our proposed algorithm performs projected gradient descent based on a novel semi-stochastic gradient specifically designed for low-rank matrix recovery. Based upon the mild restricted strong conv...

For a sample of absolutely bounded i.i.d. random variables with a continuous density the cumulative distribution function of the sample variance is represented by a univariate integral over a Fourier–series. If the density is a polynomial or a trigonometrical polynomial the coefficients of this series are simple finite terms containing only the error function, the exponential function and power...

Variance and performance of two sampling plans for aflatoxins quantification in maize were evaluated. Eight lots of maize were sampled using two plans: manual, using sampling spear for kernels; and automatic, using a continuous flow to collect milled maize. Total variance and sampling, preparation, and analysis variance were determined and compared between plans through multifactor analysis of ...

Abstract The global minimum variance portfolio (GMVP) is the starting point of Markowitz mean‐variance efficient frontier. estimation GMVP weights therefore much importance for financial investors. depend only on inverse covariance matrix returns risky assets, this reason estimated are subject to substantial risk, especially in high‐dimensional settings. In paper we review recent literature tra...

Abstract Surveys with a narrow field of view can play an important role in probing cosmology, but inferences from these surveys suffer large sample variance, arising random fluctuations around the cosmic mean. The standard method for computing variance is based on two key approximations: treating perturbations linearly and survey geometry as box. We demonstrate that it lead to significant under...

It is well known that the two-sample Student t test fails to maintain its significance level when the variances of treatment groups are unequal, and, at the same time, sample sizes are unequal. However, introductory textbooks in psychology and education often maintain that the test is robust to variance heterogeneity when sample sizes are equal. The present study discloses that, for a wide vari...