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المربعات الصغرى المشذبة الموزونة لتقدير تأثير مياه الصرف الصحي في تلوث مياه نهر دجلة/ محافظة واسط

في كثير من الأحيان يفشل تحليل المربعات الصغرى (LS) تماماً في حالة وجود قيم شاذة في الظواهر المدروسة، اذ ستفقد OLS خصائصها ومن ثم تفقد صفة المقدر الخطي الجيد Beast Linear Unbiased Estimator (BLUE) لِما تسببه الشواذ Outliers من تأثير سيئ علـى نتـائج التحليـل الاحـصائي للبيانـات اذ أن وجودها يؤدي الى إرباك كبير في تحليل البيانات في حالة إستخدام الطرائق التقليدية، ولعلاج هذه المشكلة تم تطوير أساليب إحصائية جديدة بحيث لا تتأثر بالقيم الشاذة بسهولة. هذه الطرائق تمتاز بالحصانة أو (المقاومة). ولذا كانت طريقة المربعات الصغرى المشذبة Least Trimmed Squares (LTS) كبديل جيد يحقق نتائج أكثر مقبولية وأمثليه. الاّ انه يمكن افتراض أوزان تأخذ بنظر العناية مواقع تواجد القيم الشاذة في البيانات وتحددها بشكل دقيق. ولزيادة قوة التقدير بطريقة المربعات الصغرى المشذبة الموزونة Weighted Least Trimmed Squares (WLTS) هو بأعاده الوزن لبيانات العينة حول المقدر المطلوب بصورة تكرارية وهو ما سيدعى طريقة المربعات الصغرى المشذبة المعاد وزنها Reweighted Least Trimmed Squares (RWLTS). ولتحقيق هذا البحث استدعت الحاجة الكشف والتقصّي عن تأثير التلوث مياه نهر دجلة في محافظة واسط بسبب مياه الصرف الصحي وبالذات التلوث بالمواد الصلبة غير الذائبة في الماءTotal Dissolved Solids  (TDS) وتأثير ثلاث ملوثات أملاح الكبريتات Sulphates (SO4)، الكلورايدات Chlorides (Cl) والفوسفات Phosphates ((PO4 على ذلك. وتم تقديم ذلك بدراسة احصائية وتقييمها بشكل دقيق ورفعها الى الجهات المختصّة ولتحقيق هذا الهدف تم استعمال بحجم عينة (91) موقع تم سحبها وفحصها في مختبرات بلدية محافظة واسط. وتم إجراء التحليل باستعمال برنامج MATLAB-R2015b)).  

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Publication Date
Fri Sep 30 2022
Journal Name
Journal Of Economics And Administrative Sciences
Choosing the best method for estimating the survival function of inverse Gompertz distribution by using Integral mean squares error (IMSE)

In this research , we study the inverse Gompertz distribution (IG) and estimate the  survival function of the distribution , and the survival function was evaluated using three methods (the Maximum likelihood, least squares, and percentiles estimators) and choosing the best method estimation ,as it was found that the best method for estimating the survival function is the squares-least method because it has the lowest IMSE and for all sample sizes

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Publication Date
Thu Dec 01 2011
Journal Name
Journal Of Economics And Administrative Sciences
Detecting Outliers In Multiple Linear Regression

It is well-known that the existence of outliers in the data will adversely affect the efficiency of estimation and results of the current study. In this paper four methods will be studied to detect outliers for the multiple linear regression model in two cases :  first, in real data; and secondly,  after adding the outliers to data and the attempt to detect it. The study is conducted for samples with different sizes, and uses three measures for  comparing between these methods . These three measures are : the mask, dumping and standard error of the estimate.

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Publication Date
Mon Jun 05 2023
Journal Name
Journal Of Engineering
Monitoring of the Vertical Settlement In Heavy Structures By Precise Levelling

Monitoring and analysing of the vertical deformations or the settlements of the structures is one of the main research fields in geodetic applications, which is considered a precise periodic measurement, made at different epochs to investigate these deformations on heavy structures.
In this research, the deformation measurements were carried out on one of Baghdad University buildings,” Building of Computers Department” of dimensions (70.0 * 81.3 m.). Due to some cracks observed in their walls, it was necessary to monitor the vertical displacement of this building at some particular monitoring points by constructing a vertical network and measured in different epochs. The first epoch (zero epoch) was carried out in April 2006, the

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Publication Date
Tue Sep 08 2020
Journal Name
Baghdad Science Journal
A comparison among Different Methods for Estimating Regression Parameters with Autocorrelation Problem under Exponentially Distributed Error

Multiple linear regressions are concerned with studying and analyzing the relationship between the dependent variable and a set of explanatory variables. From this relationship the values of variables are predicted. In this paper the multiple linear regression model and three covariates were studied in the presence of the problem of auto-correlation of errors when the random error distributed the distribution of exponential. Three methods were compared (general least squares, M robust, and Laplace robust method). We have employed the simulation studies and calculated the statistical standard mean squares error with sample sizes (15, 30, 60, 100). Further we applied the best method on the real experiment data representing the varieties of

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Publication Date
Mon Sep 16 2019
Journal Name
Ibn Al-haitham Journal For Pure And Applied Sciences
Different Estimation Methods of the Stress-Strength Reliability Power Distribution

      This paper deals with estimation of the reliability system in the stress- strength model of the shape parameter for the power distribution. The proposed approach has been including different estimations methods such as Maximum likelihood method, Shrinkage estimation methods, least square method and Moment method. Comparisons process had been carried out between the various employed estimation methods with using the mean square error criteria via Matlab software package.

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Publication Date
Thu Sep 30 2021
Journal Name
Journal Of Economics And Administrative Sciences
Comparison of Some Methods for Estimating Mixture of Linear Regression Models with Application

 A mixture model is used to model data that come from more than one component. In recent years, it became an effective tool in drawing inferences about the complex data that we might come across in real life. Moreover, it can represent a tremendous confirmatory tool in classification observations based on similarities amongst them. In this paper, several mixture regression-based methods were conducted under the assumption that the data come from a finite number of components. A comparison of these methods has been made according to their results in estimating component parameters. Also, observation membership has been inferred and assessed for these methods. The results showed that the flexible mixture model outperformed the others

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Publication Date
Thu Sep 30 2021
Journal Name
Journal Of Economics And Administrative Sciences
Comparison of Some Methods for Estimating Mixture of Linear Regression Models with Application

 A mixture model is used to model data that come from more than one component. In recent years, it became an effective tool in drawing inferences about the complex data that we might come across in real life. Moreover, it can represent a tremendous confirmatory tool in classification observations based on similarities amongst them. In this paper, several mixture regression-based methods were conducted under the assumption that the data come from a finite number of components. A comparison of these methods has been made according to their results in estimating component parameters. Also, observation membership has been inferred and assessed for these methods. The results showed that the flexible mixture model outperformed the

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Publication Date
Fri Sep 30 2022
Journal Name
Journal Of Economics And Administrative Sciences
Robust Estimation OF The Partial Regression Model Using Wavelet Thresholding

            Semi-parametric regression models have been studied in a variety of applications and scientific fields due to their high flexibility in dealing with data that has problems, as they are characterized by the ease of interpretation of the parameter part while retaining the flexibility of the non-parametric part. The response variable or explanatory variables can have outliers, and the OLS approach have the sensitivity to outliers. To address this issue, robust (resistance) methods were used, which are less sensitive in the presence of outlier values in the data. This study aims to estimate the partial regression model using the robust estimation method with the wavel

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Publication Date
Mon Jun 05 2023
Journal Name
Journal Of Engineering
Prediction of Compressive Strength of Reinforced Concrete Structural Elements by Using Combined Non-Destructive Tests

This research is devoted to investigate relationship between both Ultrasonic Pulse Velocity and Rebound Number (Hammer Test) with cube compressive strength and also to study the effect of steel reinforcement on these relationships.
A study was carried out on 32 scale model reinforced concrete elements. Non destructive testing campaign (mainly ultrasonic and rebound hammer tests) made on the same elements. About 72 concrete cubes (15 X 15 X15) were taken from the concrete mixes to check the compressive strength.. Data analyzed.Include the possible correlations between non destructive testing (NDT) and compressive strength (DT) Statistical approach is used for this purpose. A new relationships obtained from correlations results is give

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Publication Date
Sun Jun 20 2021
Journal Name
Baghdad Science Journal
Comparison of Some of Estimation methods of Stress-Strength Model: R = P(Y < X < Z)

In this study, the stress-strength model R = P(Y < X < Z)  is discussed as an important parts of reliability system by assuming that the random variables follow Invers Rayleigh Distribution. Some traditional estimation methods are used    to estimate the parameters  namely; Maximum Likelihood, Moment method, and Uniformly Minimum Variance Unbiased estimator and Shrinkage estimator using three types of shrinkage weight factors. As well as, Monte Carlo simulation are used to compare the estimation methods based on mean squared error criteria.  

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