Preferred Language
Articles
/
jeasiq-2212
Comparison Between Nelson-Olson Method and Two-Stage Limited Dependent Variables (2SLDV ) Method for the Estimation of a Simultaneous Equations System (Tobit Model)
...Show More Authors

This study relates to  the estimation of  a simultaneous equations system for the Tobit model where the dependent variables  ( )  are limited, and this will affect the method to choose the good estimator. So, we will use new estimations methods  different from the classical methods, which if used in such a case, will produce biased and inconsistent estimators which is (Nelson-Olson) method  and  Two- Stage limited dependent variables(2SLDV) method  to get of estimators that hold characteristics the good estimator .

That is , parameters will be estimated for the limited variables and find the variance-covariance  matrix for extracted estimators  by  the  aforementioned two methods and then compare between the results of the two methods and find any better method by estimation and then finding the estimation efficiency, and this is what the study aims to .

A simultaneous equations system will be imposed for the limited model defined by two equations containing  two endogenous variables one of complete observations and the other censored at zero.   

The two methods were used to analyze the relationship between income and family expenditure on durable consumer goods , where the results showed that the performance of (Nelson-Olson) method is better than performing the Two-Stage limited dependent variables (2SLDV) method in obtain the lower values and all comparison measures as well as the results showed that income and expenditure   one affects the other and the  

  and the price affects the income and expenditure

Crossref
View Publication Preview PDF
Quick Preview PDF
Publication Date
Thu Feb 01 2018
Journal Name
Journal Of Economics And Administrative Sciences
Use Simulation To Differentiate Between Some Modern Methods To the Model GM(1,1) To Find Missing Values And Estimate Parameters With A Practical Application
...Show More Authors

Abstract

       The grey system model GM(1,1) is the model of the prediction of the time series and the basis of the grey theory. This research presents the methods for estimating parameters of the grey model GM(1,1) is the accumulative method (ACC), the exponential method (EXP), modified exponential method (Mod EXP) and the Particle Swarm Optimization method (PSO). These methods were compared based on the Mean square error (MSE) and the Mean Absolute percentage error (MAPE) as a basis comparator and the simulation method was adopted for the best of the four methods, The best method was obtained and then applied to real data. This data represents the consumption rate of two types of oils a he

... Show More
View Publication Preview PDF
Crossref
Publication Date
Fri Mar 01 2024
Journal Name
Baghdad Science Journal
A Comparison between Ericson's Formulae Results and Experimental Data Using New Formulae of Single Particle Level Density
...Show More Authors

The partial level density PLD of pre-equilibrium reactions that are described by Ericson’s formula has been studied using different formulae of single particle level density . The parameter  was used from the equidistant spacing model (ESM) model and the non- equidistant spacing model (non-ESM) and another formula of  are derived from the relation between  and level density parameter . The formulae used to derive  are the Roher formula, Egidy formula, Yukawa formula, and Thomas –Fermi formula. The partial level density results that depend on  from the Thomas-Fermi formula show a good agreement with the experimental data.

View Publication Preview PDF
Scopus Crossref
Publication Date
Fri Sep 30 2022
Journal Name
Iraqi Geological Journal
Estimation of Initial Oil in Place for Buzurgan Oil Field by Using Volumetric Method and Reservoir Simulation Method
...Show More Authors

The estimation of the initial oil in place is a crucial topic in the period of exploration, appraisal, and development of the reservoir. In the current work, two conventional methods were used to determine the Initial Oil in Place. These two methods are a volumetric method and a reservoir simulation method. Moreover, each method requires a type of data whereet al the volumetric method depends on geological, core, well log and petrophysical properties data while the reservoir simulation method also needs capillary pressure versus water saturation, fluid production and static pressure data for all active wells at the Mishrif reservoir. The petrophysical properties for the studied reservoir is calculated using neural network technique

... Show More
View Publication
Scopus (6)
Scopus Crossref
Publication Date
Tue Feb 01 2022
Journal Name
Baghdad Science Journal
Numerical Solution for Linear State Space Systems using Haar Wavelets Method
...Show More Authors

In this research, Haar wavelets method has been utilized to approximate a numerical solution for Linear state space systems. The solution technique is used Haar wavelet functions and Haar wavelet operational matrix with the operation to transform the state space system into a system of linear algebraic equations which can be resolved by MATLAB over an interval from 0 to . The exactness of the state variables can be enhanced by increasing the Haar wavelet resolution. The method has been applied for different examples and the simulation results have been illustrated in graphics and compared with the exact solution.

View Publication Preview PDF
Scopus (2)
Scopus Clarivate Crossref
Publication Date
Sat Oct 01 2022
Journal Name
Journal Of Computational Science
Novel approximate solution for fractional differential equations by the optimal variational iteration method
...Show More Authors

Crossref (30)
Clarivate Crossref
Publication Date
Sat Oct 01 2022
Journal Name
Journal Of Computational Science
Novel approximate solution for fractional differential equations by the optimal variational iteration method
...Show More Authors

View Publication
Crossref (30)
Crossref
Publication Date
Sat Jun 07 2025
Journal Name
Journal Of Engineering
Computational Method for Unsteady Motion of Two-Dimensional Airfoil
...Show More Authors

A numerical method is developed for calculation of the wake geometry and aerodynamic forces on two-dimensional airfoil under going an arbitrary unsteady motion in an inviscid incompressible flow (panel method). The method is applied to sudden change in airfoil incidence angle and airfoil oscillations at high reduced frequency. The effect of non-linear wake on the unsteady aerodynamic properties and oscillatory amplitude on wake rollup and aerodynamic forces has been studied. The results of the present method shows good accuracy as compared with flat plate and for unsteady motion with heaving and pitching oscillation the present method also shows good trend with the experimental results taken from published data. The method shows good result

... Show More
View Publication
Publication Date
Tue Mar 01 2016
Journal Name
Al-academy
THE METHOD OF EXPRESSION IN INNATE AND POPULAR IRAQI SCULPTURAL CONTEMPORARY STUDYING BETWEEN (Hadi KadhimNassif) and (Ibrahim al nakash): كفاح عبد المجيد
...Show More Authors

The innate art,is a major tributary in the art world, It is a bold achievement, has a special flavor, With self-identity, linked to the origins and roots of human ,That goes back to the past and the history and culture of peoples. This business is not limited to only aesthetic side, but is loaded with religious and magical experience, and have social functions, This creations stayed live, breathe, grow, and change with the transformation of society, these processors emerged, from local people have not been trained academically.Their Elvis came from community culture,Which are, Mesopotamian thoroughbreds.This culture that we desperately need today, in order to increase ourselves Iraqi force, In the face of the modern world, which is locke

... Show More
View Publication Preview PDF
Crossref
Publication Date
Mon Oct 01 2018
Journal Name
Journal Of Economics And Administrative Sciences
Comparison of the statistical methods used to Forecast the size of the Iraqi GDP for the two sectors (public and private) for the period (2025-2016)
...Show More Authors

Gross domestic product (GDP) is an important measure of the size of the economy's production. Economists use this term to determine the extent of decline and growth in the economies of countries. It is also used to determine the order of countries and compare them to each other. The research aims at describing and analyzing the GDP during the period from 1980 to 2015 and for the public and private sectors and then forecasting GDP in subsequent years until 2025. To achieve this goal, two methods were used: linear and nonlinear regression. The second method in the time series analysis of the Box-Jenkins models and the using of statistical package (Minitab17), (GRETLW32)) to extract the results, and then comparing the two methods, T

... Show More
View Publication Preview PDF
Crossref
Publication Date
Sun Oct 01 2017
Journal Name
Journal Of Economics And Administrative Sciences
Statistical testing mediation in structural equations models variables with practical application
...Show More Authors

Abstract:
       This study is studied one method of estimation and testing parameters mediating variables in a structural equations model SEM is causal steps method, in order to identify and know the variables that have indirect effects by estimating and testing mediation variables parameters by the above way and then applied to Iraq Women Integrated Social and Health Survey (I-WISH) for year 2011 from the Ministry of planning - Central statistical organization to identify if the  variables having the effect of mediation in the model by the step causal methods by using AMOS program V.23, it
was the independent variable X represents a phenomenon studied (cultural case of the

... Show More
View Publication Preview PDF
Crossref