A linear model based on the spherical coordinate system is employed for tting a spherical surface to a data set obtained by a coordinate measuring machine (CMM). In practice, measurement data may have unequal accuracy on the diierent coordinate axes, thus a liner model with heteroscedastic variance of random errors is considered. A feasible weighted least squares estimate is proposed and its su...

The Lasso achieves variance reduction and variable selection by solving an 1-regularized least squares problem. Huang (2003) claims that ‘there always exists an interval of regularization parameter values such that the corresponding mean squared prediction error for the Lasso estimator is smaller than for the ordinary least square estimator’. This result is correct. However, its proof in Huang ...

The study was designed to investigate the comparative analysis of agricultural credit users and non-users among cassava farmers in Ohafia Local Government Area of Abia State. A sample of 50 credit users and 50 non-credit user cassava-based farmers were selected by multistage random sampling technique. Data were collected with a well structured questionnaire administered to a total of 100 random...

This study was conducted in Abia state, Nigeria with specific objectives to: describe socio economic characteristics of ADP and non-ADP contact farmers; estimate profitability level of the two farmer groups; compare profitability of cassava production among the two farmer groups; determine factors that influence profitability of ADP and non-ADP contact cassava farmers and identify problems cons...

This appendix contains additional analyses that we mention but do not report in the paper to preserve space.  Table IA.1: Cross-sectional gravity models (baseline equation (2)) on a sample that includes the natural resources industries.  Table IA.2: Cross-sectional gravity models (baseline equation (2)) with acquirer and target country fixed effects (instead of acquirer and target country cha...

In seepage problems, the coefficients of permeability in Laplace equation are usually assumed to be constant vs. both space and time; but in reality these coefficients are variable. In this study, the effect of material deformation due to external loads (consolidation) and variation of head in the consolidation process are considered. For the first case, formulation of kx and ky can be defined ...

Ordinary least square regression is one of the most widely used statistical methods. However, it is a parametric model and relies on assumptions that are often not met. Alternative methods of regression for continuous dependent variables relax these assumptions in various ways. This paper will explore PROCS such as QUANTREG, ADAPTIVEREG and TRANSREG for these data.

We consider the least-squares finite element method (lsfem) for systems of nonlinear ordinary differential equations, and establish an optimal error estimate this when piecewise linear elements are used. The main assumptions that vector field is sufficiently smooth local Lipschitz constant as well operator norm Jacobian matrix associated with nonlinearity small, restricted to a suitable neighbo...

Regression via ordinary least squares (OLS) is a commonly applied statistical technique in political science. However, when the dependent variable is dichotomous (0-1) rather than continuous, ordinary least squares becomes an inefficient estimation technique, and the underlying linear probability model (LPM) that is being estimated represents a poor apriori choice of model specification (Aldric...