DETERMINATION OF PARAMETERS FOR CORRELATED DAE OF A GENERALIZED LEAST SQUARES CRITERION INVOLVING LINEARIZED RESIDUALS

An inverse numerical method that estimate parameters of dynamic mathematical models given some information about unknown trajectories at some time is applied to examples taken from Biology and Ecology. The method consisting of determining an over-determined system of algebraic equations using experimental data. The solution of the over-determined system is then obtained using, for example the least-squares method. To illustrate the effectiveness of the method an analysis of examples and corresponding numerical example are presented.

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Regression Analysis and Determination of Activity Coefficients of Cd-Pb Alloy

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.311-313.736 ◽

2011 ◽

Vol 311-313 ◽

pp. 736-741

Author(s):

Shun Zhong Yao ◽

Yong Nian Dai ◽

Hao Huang ◽

Xiao Hong Wan

Keyword(s):

Regression Analysis ◽

Least Squares ◽

Activity Coefficients ◽

Reference Data ◽

Generalized Least Squares ◽

Chemical Compositions ◽

Cadmium And Lead ◽

Determination Of Activity

Chemical compositions of Cadmium and lead were measured with conditions that the temperature between 400-700°C and remaining pressure of 10-60 Pa as in which Materials containing Cadmium and lead evaporate. Activity coefficients of cadmium and lead were calculated using the generalized least squares（GLS）, three relations were deduced in Cd-Pb system，namely relation between activity coefficients and temperatures, relation between activity coefficients and chemical compositions, and that of activity coefficients and temperatures together with chemical compositions. This article provides a theoretical reference data for separation of alloys in cadmium systems.

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Determination of Estimators with Minimum Asymptotic Covariance Matrices

Econometric Theory ◽

10.1017/s026646660000801x ◽

1993 ◽

Vol 9 (4) ◽

pp. 633-648 ◽

Cited By ~ 13

Author(s):

Charles E. Bates ◽

Halbert White

Keyword(s):

Least Squares ◽

Rate Of Convergence ◽

Asymptotic Variance ◽

Generalized Least Squares ◽

Covariance Matrices ◽

Variance Estimator ◽

Objective Functions ◽

Generalized Least Squares Estimator ◽

Asymptotic Covariance

We give a straightforward condition sufficient for determining the minimum asymptotic variance estimator in certain classes of estimators relevant to econometrics. These classes are relatively broad, as they include extremum estimation with smooth or nonsmooth objective functions; also, the rate of convergence to the asymptotic distribution is not required to be n−½. We present examples illustrating the content of our result. In particular, we apply our result to a class of weighted Huber estimators, and obtain, among other things, analogs of the generalized least-squares estimator for least Lp-estimation, 1 ≤ p < ∞.

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Effect of exchange rate on trade of Afghanistan with its trade partners

Kateb Quarterly Scientific Research journal ◽

10.32592/kqsrj.2020.7.16.1 ◽

2020 ◽

pp. 9-23

Keyword(s):

Exchange Rate ◽

Least Squares ◽

Generalized Least Squares ◽

Ordinary Least Squares ◽

Trade Partner ◽

Independent Variable ◽

The Exchange Rate ◽

Trade Partners ◽

India And China

The exchange rate is one of the most significant variables in the determination of export or import amount, and its shifts cause decrease and increase in the amount of foreign trade, so it is a prominent economic variable for trade policymaking in developing countries. This topic seeks to investigate the effect of exchange rate on Afghanistan’s do business with its partners that includes: Iran, Pakistan, India, and China. Data collected monthly from 2015 through 2017; and also time serious data used for analyses that there are one dependent variable and one independent variable. The ordinary least-squares (OLS) and generalized least squares (GLS) methods estimate 16 models. Results show that the exchange rate of trade partner of Afghanistan has insignificant effects on Afghanistan trade or Afghanistan exchange rate show unimportant effects on Afghanistan trade partners. In some models which coefficients are significant, the R2 is so small, and it shows a low level of explaining. 4 models are useful among the 16 models. Finally, we can say that the exchange rate of Afghanistan and its trade partners don’t affect the trade amount.

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