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مقارنة الانحدار الشرائحي المعكوس مع المركبات الرئيسة في اختزال البيانات ذات الابعاد العالية بأستعمال المحاكاة
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 يدرس هذا البحث طرائق اختزال الابعاد التي تعمل على تجاوز مشكلة البعدية عندما تفشل الطرائق التقليدية في ايجاد تقدير جيد للمعلمات، لذلك يتوجب التعامل مع هذه المشكلة بشكل مباشر. ومن اجل ذلك، يجب التخلص من هذه المشكلة لذا تم استعمال اسلوبين لحل مشكلة البيانات ذات الابعاد العالية الاسلوب الاول طريقة الانحدار الشرائحي المعكوس SIR ) ) والتي تعتبر طريقة غير كلاسيكية  وكذلك طريقة ( WSIR ) المقترحة والاسلوب الثاني طريقة المركبات الرئيسة ( PCA ) وهي الطريقة العامة المستخدمة في اختزال الابعاد ,  ان عمل طريقة انحدار الشرائحي المعكوس SIR ) ) و طريقة المركبات الرئيسة (PCA) يقوم على عمل توليفات خطية مختزلة من مجموعة جزئية من المتغيرات التوضيحية الأصلية والتي قد تعاني من مشكلة عدم التجانس ومن مشكلة التعدد الخطي بين معظم المتغيرات التوضيحية , وستقوم هذه التوليفات الجديدة المتمثلة بالمركبات الخطية الناتجة من الطريقتين بإختزال أكثر عدد من المتغيرات التوضيحية للوصول الى بُعد جديد واحد او اكثر  يسمى بالبعد الفعّال . وسيتم استعمال معيار جذر متوسط مربعات الخطأ للمقارنة بين الاسلوبين لبيان  افضلية الطرائق , وقد تم اجراء دراسة محاكاة للمقارنة بين الطرائق المستعملة  وقد بينت نتائج المحاكاة ان طريقة weight standard Sir  المقترحة هي الافضل .

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Publication Date
Sun Jan 01 2017
Journal Name
مجلة العلوم الاقتصادية والإدارية
مقارنة بين أنموذج الانحدار اللوجستي وانموذج التحليل المميز الخطي بأستعمال المركبات الرئيسية لبيانات البطالة لمحافظة بغداد
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ان الهدف من الدراسة هو بيان القدرة التنبؤية الافضل بين انموذج الانحدار اللوجستي والدالة المميزة الخطية باستعمال البيانات الاصليه اولا ثم المركبات الرئيسة لتقليص الابعاد بين المتغيرات لبيانات المسح الاجتماعي والاقتصادي للاسرة لمحافظة بغداد لعام 2012 وتضمنت عينة البحث 615 مفردة لـ13 متغير، 12منها متغير توضيحي والمتغير المعتمد شمل العاملين والعاطلين عن العمل، تم اجراء المقارنة بين الطريقتين اعلاه واتضح من خلال

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Publication Date
Thu Mar 01 2007
Journal Name
Journal Of Economics And Administrative Sciences
مقارنة الأساليب المستخدمة في تحديد عدد المركبات الرئيسية مع التطبيق العملي
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The principal components analysis is used in analyzing many economic and social phenomena; and one of them is related to a large group in our society who are the university instructors. This phenomenon is the delay occurred in getting university instructor to his next scientific title. And as the determination of the principal components number inside the principal components depends on using many methods, we have compared between three of these methods that are: (BARTLETT, SCREE DIAGRAM, JOLLIFFE).

     We concluded that JOLLIFFE method was the best one in analyzing the studying phenomenon data among these three methods, we found the most distinguishing factors effecting on t

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Publication Date
Mon Sep 01 2008
Journal Name
Journal Of Economics And Administrative Sciences
مقارنة طرائق تقدير معلمات توزيع كاما ذي المعلمتين في حالة البيانات المفقودة باستخدام المحاكاة
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The estimation of the parameters of Two Parameters Gamma Distribution in case of missing data has been made by using two important methods: the Maximum Likelihood Method and the Shrinkage Method. The former one consists of three methods to solve the MLE non-linear equation by which the estimators of the maximum likelihood can be obtained: Newton-Raphson, Thom and Sinha methods. Thom and Sinha methods are developed by the researcher to be suitable in case of missing data. Furthermore, the Bowman, Shenton and Lam Method, which depends on the Three Parameters Gamma Distribution to get the maximum likelihood estimators, has been developed. A comparison has been made between the methods in the experimental aspect to find the best meth

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Publication Date
Fri Dec 01 2017
Journal Name
Journal Of Economics And Administrative Sciences
مقارنة مقدر بيز مع طريقة الامكان الاعظم لتقدير معلمتي معكوس التوزيع الاسي المعمم في حالة ضبابية البيانات
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In this paper, the generalized inverted exponential distribution is considered as one of the most important distributions in studying failure times. A shape and scale parameters of the distribution have been estimated after removing the fuzziness that characterizes its data because they are triangular fuzzy numbers. To convert the fuzzy data to crisp data the researcher has used the centroid method. Hence the studied distribution has two parameters which show a difficulty in separating and estimating them directly of the MLE method. The Newton-Raphson method has been used.

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Publication Date
Tue Jun 01 2010
Journal Name
Journal Of Economics And Administrative Sciences
دراسة مقارنة بين بعض الطرائق الحصينة في تقدير معلمات انموذج الانحدار الخطي باستخدام اسلوب المحاكاة التجريبي في حالة وجود بيانات تتضمن مشاهدات شاذة
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In linear regression, an outlier is an observation with large residual.  In other words, it is an observation whose dependent-variable value is unusual given its values on the predictor variables. An outlier observation may indicate a data entry error or other problem.

An observation with an extreme value on a predictor variable is a point with high leverage. Leverage is a measure of how far an independent variable deviates from its mean. These leverage points can have an effect on the estimate of regression coefficients.

Robust estimation for regression parameters deals with cases that have very high leverage, and cases that are outliers. Robust estimation is essentially a

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Publication Date
Tue Jan 01 2019
Journal Name
مجلة العلوم الاقتصادية والإدارية
مقارنة الخوارزمية الجينية مع طريقتي المربعات الصغرى اللاخطية والامكان الاعظم اللاخطي باستخدام المحاكاة لتقدير انموذج BoxBOD اللاخطي باستخدام المحاكاة
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In this research, one of the nonlinear regression models is studied, which is BoxBOD, which is characterized by nonlinear parameters, as the difficulty of this model lies in estimating its parameters for being nonlinear, as its parameters were estimated by some traditional methods, namely the method of non-linear least squares and the greatest possible method and one of the methods of artificial intelligence, it is a genetic algorithm, as this algorithm was based on two types of functions, one of which is the function of the sum of squares of error and the second is the function of possibility. For comparison between the methods used in the research, the comparison scale was based on the average error squares, and for the purpose of data ge

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Publication Date
Tue Jun 01 2010
Journal Name
Journal Of Economics And Administrative Sciences
مقارنة بعض المقدّرات الحصينة في دوال التمييز بأستخدام المحاكاة
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The development in manufacturing computers from both (Hardware and Software) sides, make complicated robust estimators became computable and gave us new way of dealing with the data, when classical discriminant methods failed in achieving its optimal properties especially when data contains a percentage of outliers. Thus, the inability to have the minimum probability of misclassification. The research aim to compare robust estimators which are resistant to outlier influence like robust H estimator, robust S estimator and robust MCD estimator, also robustify misclassification probability with showing outlier influence on the percentage of misclassification when using classical methods. ,the other

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Publication Date
Wed Nov 01 2017
Journal Name
Journal Of Economics And Administrative Sciences
المحددات الاقتصادية والاجتماعية للبطالة في السودان -دراسة قياسية باستخدام انحدار المركبات الرئيسة للمدة (1981-2015م)
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Considering the magnitude of its economic, social and political impact, unemployment represents a crucial challenge confronting the majority of the countries of the world. The problem of the study was the high rates of unemployment in Sudan and the inability of economic growth rates to keep pace with the steady increases in unemployment rates during the study period. This study aimed to identify the economic and social variables influencing unemployment rate in Sudan, in addition to measuring the impact of these variables over the period (1981-2015). Data were collected from databases of the World Bank and Atlas of the World's data .The study hypothesized the presence of statistically significant and direct relationship between u

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Publication Date
Wed Dec 01 2010
Journal Name
Journal Of Economics And Administrative Sciences
مقارنة بين طرائق تقدير معالم الانحدار عند وجود مشكلة عدم تجانس التباين مع التطبيق العملي
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In this research weights, which are used, are estimated using General Least Square Estimation to estimate simple linear regression parameters when the depended variable, which is used, consists of two classes attributes variable (for Heteroscedastic problem) depending on Sequential Bayesian Approach instead of the Classical approach used before, Bayes approach provides the mechanism of tackling observations one by one in a sequential way, i .e each new observation will add a new piece of information for estimating the parameter of probability estimation of certain phenomenon of Bernoulli trials who research the depended variable in simple regression  linear equation. in addition to the information deduced from the past exper

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Publication Date
Fri Apr 01 2016
Journal Name
Journal Of Economics And Administrative Sciences
التنبؤ بقيم السلاسل الزمنية بأستعمال أنموذج (ARMAX) مع تطبيق عملي
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Abstract :

          Researchers have great interest in studying the black box models this thesis has been focused in the study one of the black box models , a ARMAX model which is one of the important models and can be accessed through a number of special cases which models (AR , MA , ARMA, ARX) , which combines method of the time series that depend on historical data and and regression method as explanatory variables addition to that past errors , ARMAX model importance has appeared in many areas of application that direct contact with our daily lives , it consists of constructing ARMAX model several traditional stages of the process , a iden

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