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طرائق تقدير عدد مرات الفشل في الانظمة القابلة للاصلاح

Author name: ثائر فيصل شاهر
Supervisor name: عبد المجيد حمزة الناصر
Specific topic: Statistics
Degree: Doctorate
Language: Arabic
University location: Baghdad
First pages:
Abstract: ان الهدف من هذا البحث تسليط الضوء على احد اهم وابرز المواضيع المعاصرة في دراسات المعولية وهو الانظمة القابلة للاصلاح والذي يعني ان النظام الذي عندما يحدث فيه فشل فيمكن اعادته للعمل باصلاح بعض مركباته دون الحاجة الى ابدالها. والذي يحظى بتطبيقات واسعة وخاص | The main purpose of this research was to study one of the main modern subject which is very important in the reliability studies, it is the repairable system, which means that if the component fails it immediately repaired.These studies have widely applications in many systems like watching machine of cars, airplanes and communication systems, that is failure make huge materiel and humane losses.It is found that these systems submit to Poisson process in particular the nonhomogenous Poisson process, the main contribution in this research is the modification in estimating the number of failures in repairable systems, and the derivation the distribution of n - failures where the distribution is General Gamma.Finally, some new results obtain and a simulation experiments were done to compare the proposed and classical methods.

مقارنة مقدرات بيز الحصين مع مقدرات اخرى لتقدير دالة المعولية التقريبية لتوزيع ويبل == A Comparison of Robust Bayesian Estimators With Another Estimators To Estimate The Approximation of Reliability Function For Weibull Distribution

Author name: تهاني مهدي عباس الياسري
Supervisor name: مهدي محسن اسماعيل العلاق
Specific topic: Statistics
Degree: Doctorate
Language: Arabic
University location: Baghdad
First pages:
Abstract: من الملاحظ ان معظم البحوث والدراسات في مجال الاحصاء ولاسيما في حقل المعولية تهدف الى الحصول على مقدرات ذات مستوى عال من الكفاءة. لاسيما عندما تكون بيانات العينة قيد الدراسة ملوثة. او في حالة عدم التحديد الدقيق للمعلومات المسبقة او في حالة ظهور الحالتين م | It is noticed that most of the researches and studies in the field of statistics particularly in the field of reliability aiming to obtain estimators of very high standard of competency specially when the sample data under study is contaminated, or in the case of not determining accurately the previous information or in case both cases appear together. From here came the objective of the thesis to come to competent estimators of the approximate reliability of Weibull distribution which is considered one of the common failure models. Through studying the ordinary procedures represented in the maximum likelihood method and method of moments and white’s method as well as the ordinary robust methods represented by the method of M - estimate and bayes procedure as well. Therefore bayes procedure was suggested depending on natural conjugate prior function in addition to suggesting three methods according to robust bayes procedure where the first suggested procedure of robust bayes assumed that there is an extent of belief and to a certain percentage with the researcher (the percentage of the researcher falling into mistake in determining the primary information) where the accurate determination of the primary information has already been made which will be integrated with the sample prospects to obtain bayes estimater As to the second suggested procedure of the robust bayes it treated the problem of the sample prospects contamination or the primary information. Whereas the third robust bayes procedure suggestion had treated the problem of appearance of both problems together - that is inaccuracy in determining the primary information and the possibility of contamination to the sample views or the primary views as well, found a comparison between the studied evaluation methods by using the simulation procedure. It has been arrived to the success of the suggested methods in evaluating the approximate reliability of Weibull distribution depending on the two statistical scales (Integral Mean Square Error) (IMSE) and the (Integral Mean Absolute Percentage Error) (IMAPE).

تقدير دالة المعوليـة لتوزيع لوغارتيم الطبيعي مع تطبيق عملي == Estimate of Reliability Function For Lognormal Distribution With Practical Application

Author name: بلسم مصطفى شفيق النائب
Supervisor name: صباح هادي عبود الجاسم | فرحان اسماعيل العاني
Specific topic: Statistics
Degree: Master
Language: Arabic
University location: Baghdad
First pages:
Abstract: لقد كان الاهتمام الواسع والمتزايد في دراسة موضوع المعولية في السنوات الاخيرة يعود الى التطور التكنولوجـي والتقني السريـع واستخدام الانظمـة الالكترونية المعقـدة في مختلف المجالات. وعليه فان دراسة موضوع المعولية والربط بين الجانبين النظري والتطبيقي امر له | The studies of the subject - matter of Reliability with connecting between theoretical and application sides , it is an important matter now a days because the technology development with using electronic systems.In this study it is used the Lognormal Distribution as a failure models when the failure rate to these models initially increases over time and then decreases approaching Zero with increasing time , and find out the estimators of reliability function by different methods.The estimates are : 1. Maximum Likelihood Estimation.2. Uniformly Minimum Variance Unbiased Estimator.3. Bayes Estimation.And then comparing between the priorities of the estimates through using the Monte - Carlo method and conducting several experiments using Mean Square Error.Generally result show that Maximum Likelihood Estimation to estimate Reliability is better than the other methods , Regarding the practical aspect the data of life time for four machines from EIGC and found after using chi - Square test that the life time for test machines distribute Lognormal and the estimation of Reliability function for machines done using Maximum Likelihood Method

تقدير معلمات انموذج المعادلات الهيكلية المتضمن متغيرات الوساطة مع تطبيق عملي == Estimation of Structural Equations Model Parameters With Practical Application

Author name: بشرى سعد جاسم
Supervisor name: غفران اسماعيل كمال
Specific topic: Statistics
Degree: Master
Language: Arabic
University location: Baghdad
First pages:
Abstract: يستعمل تحليل الانحدار مع المتغيرات المصنفة الى صنفين صنف يمثل متغيرات مستقلة (Independent variables) واخر يمثل متغيرات تابعة (Dependent variables), فلذلك يقوم تحليل الانحدار بدراسة العلاقة بين المتغيرات المستقلة والمتغيرات التابعة, الا ان هذا التحليل يعمل | regression analysis use with classified variables into two class that represents the independent variables (Independent variables) and the other is a subsidiary variables (Dependent variables), for there the regression analysis study the relationship between independent and Dependent variables, but , this analysis works to know only the direct impact between the variables for this reason i use the structural equation Model (SEM) to identify and know the variables that are of indirect effects by estimating and testing parameters by set of methods (steps causal method, bootstrap method, method of multiplying the transaction ( parameters) product of coefficients, difference in coefficientsstructural equation model like other models are a matching variables tested with the phenomenon studied , test the compatibility of the variables that make up a structural equation model, and to achieve this condition, use Confirmatory Factor Analysis (CFA) way to see match variables that compose it. After confirming the conformity of the model or suitability experimenting and having the effect of mediating variable in the model and mediation are two types : Single mediation where transmission of the influence of the independent variable to the dependent variable through the mediation of a single variable, and multiple mediation where is transition Effect independent variable x to the variable y through several mediation variables. the practical side of study include the effect of cultural stat of the man (X) in the use of violence against women (Y) through a series of mediation M_1variables represent (women's empowerment) and M_2represents (family planning) and the study data are taken from the integrated survey of social and health state for Iraqi women (I - WISH) for the year 2011 in the Ministry of planning - Central Statistics organazation, and this data applied conditions of adequate to structural equation model SEM and, and then estimate the parameters mediating variables and test their ability to move the indirect effect by the methods mentioned above using a program.AMOS V.23The researcher concluded that a moral mediation variables tested when using standard errors formulas for (Sobel and Goodman and Aroian) and compensated for in the test version of z all results be close itself in the other the researcher contrast were recommendations of the research is to use a single version of the standard errors formats (Sobel and Goodman and Aroian) to test the effect of mediating variables in the model, as the researcher found that the independent variable X (cultural condition of the man) affects the Y variable (violence against women) indirectly through mediation M_2variable (family) organization.

التنبؤ باستعمال نماذج الانحدار الذاتي العامة المشروطة بعدم تجانس التباين (GARCH) الموسمية مع تطبيق عملي == Forecasting The Use of Generalized Autoregressive Conditional Heteroscedastic Models (GARCH) Seasonality With Practical Application

Author name: بريدة برهان كاظم
Supervisor name: فارس طاھر حسن الكواز
Specific topic: Statistics
Degree: Master
Language: Arabic
University location: Baghdad
First pages:
Abstract: مما لا شك فيه، تحظى نماذج GARCH) ) بالفاعلية والشعبية الكبيرة في نمذجة البيانات الاقتصادية والمالية، اذ تسمح للتباين المشروط بالتغير عبر الزمن، مما يجعلها اكثر واقعية في المجال الاقتصادي. وتتوفر ميزة اخرى مهمة في عالم الاقتصاد، ممثلة بالموسمية، الت | Un doubtedly , The GARCH model is very popular and effectiveness in economic and financial data , since it allows the conditional variance to vary over time , which makes them more realistic for the economic world. And there is another important characteristic in the economic world , Represented seasonality , that exist in high frequency data such as daily series , it can be seen in the real data of the exchange rate IQD/USD , Because there are seasonal conditional heteroscedasticity clearly shows in this data , Thereby are dealt with this type of data using Multiplicative seasonal generalized autoregressive conditional heteroscedastic models , Because it is proven effective to express their seasonal phenomenon on the contrary GARCH models which do not contain seasonal vehicle. hence the aim of the research reaching a better model represents the seasonal data with proof of the effectiveness of the seasonal model in preference to the usual model. it has been used to detect seasonal presence in the data first , after that was diagnosed a problem of heteroscedasticity passing through the phase estimation using the conditional maximum likelihood and assuming normal distribution of errors , then determine the appropriate rank of the model using a number of special criterian Represented each of the Akaike Information Criterion (AIC), Schwartz Information Criterion (SIC) , Hannan Quinn Information Criterion (H - Q), down to the stage to predict , using two method to predict the first is the prediction in the sample , which objective was to infer the efficiency of the preferred model and the second way forecasting out of sample any prediction of future values.it is found through the application on the study data stages that the best model for predicting volatility is SGARCH (1,0)(1,0).

التحليل البيزي لنماذج الانحدار الخاصة بالبيانات المزدوجة (panel data) == Bayesian Analysis For Regression Panel Data Models

Author name: باسم شليبه مسلم عباس القيسي
Supervisor name: اموري هادي كاظم الحسناوي
Specific topic: Statistics
Degree: Doctorate
Language: Arabic
University location: Baghdad
First pages:
Abstract: تعد البيانات الاحصائية ضرورية عند دراسة اغلب ظواهر المجتمع ومنها الظواهر الاقتصادية والاجتماعية والنفسية الخ كون تحليل تللك البيانات باستخدام الاساليب الاحصائية توفر للباحث او متخذ القرار حول الظاهرة المدروسة قاعدة من المعلومات الضرورية لتسهيل عملية اتخاذ | The statistic data is important to study most of phenomena as economical , social , psychological phenomena..etc. The analysis of this data via the statistical methods gives the researcher or the decision maker more information about the studied phenomenon to make the suitable decision. The data availability needs to limit a mathematic model which represents them by the researcher and to put in consideration the type of the available data. One of the these data is panel data which can be defined ( that they are repeated measurements to the studied phenomena for N from the cross section and for T from the time series ) which can be represented by one of the model ( fixed effect model or random effect model ).Most of the studies exposed estimation of the chosen model parameters by using the classical methods as GLS and FGLS methods , whereas this research touches on the Bayesian methods to estimate parameters , especial regressive model (panel data) ,depending on the priors distributions ( non informative prior dist. and conjunct prior dist. ) and to compare them with ML method to chose the best ones for estimation and choosing.After doing two practical applications in the research ,we obtained findings. ML method was the most significant for estimating the model parameters for the fixed effect model and pooling model. Bayes method which depends on non informative prior distribution , got the second grade.When using Bayes method depending on prior distribution used in the research to estimate the fixed model parameters when the cross sections number are little to get multivariate - t posterior distribution , and if it is used with random effect model we get multivariate normal after making asymptotic expansion with existing of a loss function of the weighed squired error.

تقدير نماذج مختلطة للبيانات المصنفة مع التطبيق العملي == Estimation Mixed Models Using Catacorical Data With Application

Author name: ايناس عبد الحافظ محمد
Supervisor name: خالد ضاري عباس الطائي
Specific topic: Statistics
Degree: Doctorate
Language: Arabic
University location: Baghdad
First pages:
Abstract: يعتمد مفهوم التوزيعات المختلطة ( المركبة) في تطوير نماذج مناسبة للبيانات المصنفة , وقد تم في هذا البحث ايجاد بعض الانماذج الاحتمالية الملائمة لهذه البيانات ومن ثم العمل على تقدير معلمات هذه الانماذج.وبعد تشخيص اوتحديد نوعي التوزيعات وهما (التوزيع المركب | The concept of mixed distributions depends (composite) in the development of appropriate data seed models, has been in this research finding some models appropriate probability of this data and then work to estimate the parameters of this models. After diagnosis Aothdid two types of distributions, namely (compound beta - Bainomal (Beta - distribution Binomial) and the distribution of Ganerlized logarithmic Series distribution (GLSD)) has been working to estimate the parameters of these distributions methods usual such as way as possible (MLE) and the method of moments (Moment) and the method of Chi - square (Chi - squar) and methods of unconventional such as search cuckoo algorithm Hawwarzmih simulated annealing. The theoretical side included the concept of vehicle models and how to configure form by probabilistic normal function and methods different appreciation such as method Maximum Likelihood Function (MLE) and the method of moments (Mom) and a method to minimize Chi - square (Minimum) and methods of artificial intelligence techniques such as search cuckoo algorithm (Cock Search) algorithm simulated annealing (Simuannling) has been presented simulation has been adopted in the comparison between the estimation methods and we had simulated experiments at different volumes of samples( n= 20, 50, 100,250). And repeat each experiment R = 1000 to achieve the goal and were compared using statistical measurements (MSE, AMPE) found that the best method (cuck) which is proposed by the researcher. The researcher numbers Bernamjeh (Matlab, R2005 B) and put all the results in the tables either the practical side and having briefed researcher at data rates of disability and for the period of (2007 - 2010) obtained through the health center for the disabled has been the comparison between Models through criterion (AIC) the standard bayes Information (BIC) and the standard G2) the researcher found that the capabilities of the search cuckoo algorithm is better than during the experimental side, therefore this algorithm applied to real data to complement the tests of good matching, which enabled Khalalhl the researcher presented the practical application of the private tables results. It was found through statistical analysis that in the year (2011) has a lower standard Akaki for the distribution of the compound compared with the distribution chain logarithmic year, which indicates that it has the best modelFrom the conclusions that have been reached by using way (GIBS) in the simulation of mixed distribution and the method of rejection and acceptance (Reject, Accept) for distribution Genaralized logarithim Series is that the capabilities of the specimen landmarks using the best in terms possess the lowest average error boxes in sizes small samples search cuckoo algorithm is medium and large The rest of the roads were estimates varying values. It has been presented the recommendations that emerged from the thesis as well as future research

استخدام التحليل البيزي لنموذج انحدار خطي بسيط باستخدام اسلوب المحاكاة == The Bayes Analysis In The Model Simple Linear Regression Using Simulation

Author name: ايناس عبد الحافظ محمد
Supervisor name: محمد صادق عبد الرزاق الدوري
Specific topic: Statistics
Degree: Master
Language: Arabic
University location: Baghdad
First pages:
Abstract: تبقى عملية التقدير لمعلمات انموذج الانحدار من الموضوعات المهمة على الرغم من كثرة ما كتب عنها من خلال البحوث والدراسات التي تختلف باختلاف الاساليب المتبعة في عملية التقدير سواء كان هذا الاسلوب تقليديا او بيزيا.الغرض من هذه الدراسة هو توظيف معلومات مسبقة | The process of estimating the parameters of regression, is still one of importent Subject despite of large number of papers and studies written in this subject, these studies are differ in techniques followed in the process of estimation if this techniques classic or Bayesian. The purpose of this study to prior information about the parameters was applied which estimated according to Bayesian theory which represented by Gamma distribution with one parameter in the estimating process and for varies simple sizes then making a comparison between estimation techniques represented by (OLS) method and Bayesian techniques by providing the distribution and all techniques which deals with derivatives process to obtain the Bayesian estimation. By using the simulation technique, results has been obtained to provide the researcher the image to clarify the best method in estimation technique

استخدام نظرية الرابطة لتحليل دالة البقاء ذات المتغيرين == Using The Copula Theory For Analyzing The Bivariate Survival Function

Author name: ايمان عبد علي داود
Supervisor name: ضوية سلمان حسن الجنابي
Specific topic: Statistics
Degree: Doctorate
Language: Arabic
University location: Baghdad
First pages:
Abstract: تم في هذا البحث استعمال نظرية الرابطة (Copula Theory) في نمذجة دالة البقاء ذات المتغيرين اذ تم استعمال انموذجين يخضعان لتوزيع ويبل ذي المتغيرين وانموذج اخر يخضع للتوزيع الطبيعي ذي المتغيرين القياسي المبتور عند الصفر وبنسبة خلط واعتمادية واحجام عينات مخ | It has been concluded in this research to use the copula theory in modeling the survival function of the bivariate as two models yielding to the bivariate weibull distribution has been used and another model that submit to the bivariate standard normal cut off at zero point and mixing percentage, reliance and sizes of different specimens and a simulation experiment has been carried out for the purpose of making experimental comparison between the evaluations of the survival function mentioned above by using six different copulas in addition to two common models, the first by using the function when assuming independence and the second by using the survival function definition of the bivariate as the use of copulas has been reached which led to acquire an evaluated survival function of the bivariate with properties of more fineness than the two evaluated survival functions of the bivariate which had been acquired by using the two common models referred to above.

مقارنة بين اختبار (Gold feld Quandt) الحصين مع اختبارات اخرى للكشف عن عدم تجانس التباين بوجود القيم الشاذة == A Comparison of The Test (Gold Feld Quandt) Modified With Other Tests To Detection The Presence of Heterogeneity of Variance of Outliers Values

Author name: ايلاف بهاء علوان
Supervisor name: محمود مهدي حسن البياتي
Specific topic: Statistics
Degree: Master
Language: Arabic
University location: Baghdad
First pages:
Abstract: ان مشكلة عدم تجانس التباينات في حالة وجود القيم الشاذة لها جانبان الاول : هو كيفية تعامل الاختبارات مع مشكلة عدم تجانس التباينات في حالة وجود القيم الشاذة بالنسبة لانموذج الانحدار الخطي المتعدد حيث نلاحظ ان الاختبارات الاعتيادية (الكلاسيكية ) تعاني من مشا | The problem heterogeneity in the case of the presence of outlier values has two important sides. The first is how to handle the test, which have the problem of lack of heterogeneity in the case of outlier values for the multivariate linear regression model where we notice that the usual tests (the classical) have the problems in the results, and the results obtained will be inaccurate and misleading. Therefore, these will be unreliable results, so it is necessary to use other tests to substitute the regular tests, they will work in the same way of normal teste in the absence of the problem of heterogeneity and they are called robust tests. These tests are Modified GoldfieldQuant, Modified Bayes, and Modified levene. Different percentages of data were cut which are (10% , 25% , 40%) assuming normal distribution of data. A comparison was made of the mentioned tests by using soft ware power of the test of Monte Carlo Simalation then detect the best test by force standard where Bayes robust was the best test for detecting the problem of heterogeneity in the presence of outlier valuesand gave reliable results. In the second side, Box plot was used for the detection of outlier values in real data. As for the practical side, data from the agriculture and cultivation of planning and follow - up / meteorological center were collected and used in this study on the four variables for the year 2013 - 2014 and the variables are : Raining rate (y).Air pressure (x_1).Temperature rate (x_2).Humidity rate (x_3).

الطرائق البيزية والتقليدية في تقدير معلمات بعض نماذج بواسون غير المتجانسة مع تطبيق عملي : بحث مقارن == Bayesian And Ordinary Methods For Estimating Parameters of Some Non - Homogeneous Poisson Models With Practical Application Comparative Research

Author name: ايات صادق جعفر
Supervisor name: ايمان حسن احمد
Specific topic: Statistics
Degree: Master
Language: Arabic
University location: Baghdad
First pages:
Abstract: تعد عمليات بواسون غير المتجانسة احدى الموضوعات الاحصائية التي اصبح لها اهمية في جميع العلوم ولها تطبيقات واسعة في مختلف المجالات كنظرية صفوف الانتظار والانظمة القابلة للاصلاح وانظمة الحاسوب والاتصالات ونظرية المعولية وغيرها، كما تستعمل عمليات بواسون غير | The Non - Homogeneous Poisson process considered one of the statistical subjects which had an importance in other sciences and had a large application in different areas as the theory of waiting raws rectifiable systems, computer and communication systems and the theory of reliability and many other, also it used in modeling the phenomenon that occurred by unfixed way over time (all events that changed by time).This thesis deals with some of the basic concepts that are related to the Non - Homogeneous Poisson process, also this research mentioned two models of the Non - Homogeneous Poisson process which are the power law model , and Musa - okumto , also many different methods have been used in the estimating the parameters of the model , of which the classic methods would be used , maximum likelihood method and moment meethod to estimate the parameters of power law and Musa - Okumoto model , in addition to that the use of Bayesian method in the estimation of the parameters of the two models which are used in this research , in order to find the best way in the estimation , we referring to simulation manner in which we tested four size of samples ( 25, 50 , 75, 100) to illustrate the effect of changes in samples volume on parameters estimation , and for the sake of making a comparison between the used methods in estimation depend on the mean square error , and according to this results the maximum likelihood method is found to be the best and efficient way in estimation in which it gave the less mean square error, in addition to the models parameters by using this method was very close from the initial value that have been assumed to theparameters while the Bayesian method comes secondly in estimation Also this thesis included practical application dealing with the phenomena of earthquakes in Kirkuk province of which the time average was estimated by using maximum likelihood method and the Bayesian.

مقارنة طرائق تقدير معلمات ودالة معولية توزيع كاما ذي المعلمتين في حالة البيانات المفقودة باستخدام المحاكاة == Comparing The Estimation Methods of The Parameters And The Reliability Function For The Two Parameters Gamma Distribution In Case of Missing Data By Using Simulation

Author name: اوات سردار وادي
Supervisor name: ظافر حسين رشيد النجار
Specific topic: Statistics
Degree: Master
Language: Arabic
University location: Baghdad
First pages:
Abstract: ان اغلب طرائق التقدير الاحصائية تفترض توفر بيانات تامة المشاهدات للعينات المدروسة، وقد بنيت جميع الطرائق على هذا الاساس. ولكن في الكثير من الظواهر الطبيعية، والاقتصادية، والاجتماعية وغيرها تتعرض جزء من بيانات هذه الظواهر الى الفقدان وتختلف اسباب الفقدان ف | Most of the statistical estimation methods depend on the availability of the complete data of the observations of the samples under study. All the statistical methods are based on this basis. However, part of the data of most of the natural, economic and social phenomena is prone to be missed for several reasons. The missing of the data may happen intentionally because of the high costs, risks or the lack of capabilities or unintentionally because of the failure of the recorders, the lack of the necessary requirements of production, the natural disasters, wars etc. Regardless of the various reasons, the incomplete data gives arise to a complex problem, which must be resolved by using statistical methods that deal with the incomplete data.In most cases, the failure times data of the individual component in the system has missing observations. Most of the reasons of having missing data go back to the meter, which registers the failure times of the whole system instead of a single component. Furthermore, the maintenance employees and the operators, who register the data, are responsible for maintaining the systems or the engines which fail to operate; they are not responsible for registering the data. Hence, it is not possible to have a convenient distribution of failure times because of the missing data of the individual component during the registration and because the available data represent the whole number of the failure times and the accumulative number of the operating. Consequently, the familiar methods of estimation are inconvenient. Therefore, some researchers derive and develop certain methods to estimate the parameters and Reliability Function using this kind of non - standard data for the various distributions of failure times.The research studies the Two Parameters Gamma Distribution, which is considered one of the most important, applicable and widely used distributions in the reliability realm and Survival Theory. It is mostly used as a model to distribute the failure times of the electrical, mechanical and electromechanical systems. The estimation of the parameters and the Reliability Function of this 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 method through simulation by using the Monte Carlo Method. Several experimentations have been made by using two of the important statistical measures : Mean Square Error (MSE) and Mean Absolute Proportional Error (MAPE). Generally, the developed Thom Method is found to be the best one for the Reliability Function estimation because it has the minimum Integral Mean Square Error (IMSE) and the minimum Integral Mean Absolute Percentage Error (IMAPE) in comparison with the other methods.

بناء توزيع احتمالي لوقت الفشل المستغرق باستعمال تحويل انتروبي لتوزيع Burr Type - XII == Building Probabilistic Distribution of The Failure Time Spent Using Entropy Transformation

Author name: اسيل نوري صالح
Supervisor name: اسماء غالب جابر الراوي
Specific topic: Statistics
Degree: Master
Language: Arabic
University location: Baghdad
First pages:
Abstract: The research aims to find a probability distribution for the times of failure through function Entropy transformation using function reliability and cumulative distribution function, and after test data and found it follows the distribution of Burr TypeXII and experiencing volatility, were derived formula probability distribution of the new transfer application Entropy the probability distribution continuous Burr Type - XII and tested a new function and have found it to function probability Were derived SMA have found function probabilistic aggregate in order to adopt to generate data for the purpose of implementation of simulation experiments and research aims to compare estimate parameters probability distribution that has been extracted from the distribution formula using the methods of estimating possible Azam and the way White and estimation method proposed (appreciation mixed) and compare their adoption Metrology statistical mean square error and mean absolute error , has been using simulation for comparison between preference estimators and sizes different samples was conducted practical application to data from the General Company for electrical Industries was selected sample size (67) include electric motors until get failure in this setups.

اسقاطات السكان والقوى العاملة في محافظة نينوى للفترة (1997 - 2027) حسـب التعداد العام للسكان عام 1997 == The Population And Labor Force Projection of Ninawa For The Period (1997 - 2027)

Author name: اسيل محمود شاكر السهيل
Supervisor name: بشرى علي يعقوب الجعفري
Specific topic: Statistics
Degree: Master
Language: Arabic
University location: Baghdad
First pages:
Abstract: لقد اتجه اهتمام المفكرين والعلماء منذ عقد الثمانينات او حواليه لينصب على قضايا التشغيل ودخل الاسرة والاستهلاك، وفي ذلك دعوة واضحة للتركيز على المدخل الاجتماعي في عملية التخطيط للتنمية وعلى جانب العرض في عملية تخطيط القوى العاملة باعتبار ان هذا الجانب يشكل | In the eighties, scientists and thinkers concerned in family income, job issues, and consumption.This concern directs the attention towards the importance of social field in the development plan, and towards offer field in labor force design which is a case needs a special concern by itself since it requires the exploitation of all of the existing economical abilities to offer jobs and to manage the perfect use of national employment.The main basics of social and economical development plan are the analysis of humanity resources, the study of supply and demand field in size and structure for the available labor force in a certain country, and the predication of labor force according to the economical activities and occupation in the future.Hence, this study aims to estimate the numbers of future labor force in Nainawa governorate for the period (1997 - 2027) according to the census of (1997) which is considered as a basic year in building a future data base that depends upon true scientific facts.The aim of this study requires the estimation of the averages of economical activity for (1992) using Linear Extrapolation Method and Indirect Extrapolation Method redaction by Durand Coefficient to estimate the average of economical activity for the period (2002 - 2027).The number of people was projected by using Component Method which requires hypothesizing people variables including fertility, mortality and migration.The first step to reach the aim of this study is evaluating and adjusting the faults of data in age and qualitative structure in Nainawa governorate by using United Nation Secretariat Standard and Reduction of Effects of Age Heaping Method using unfamiliar age groups for evaluating and adjusting

تقدير معولية الانظمة باستعمال مقدرات بيز اللامعلمية وشبه المعلمية مع تطبيق عملي == System’s Reliability Using Nonparametric And Semi Parametric Bayesian Estimators With Practical Application

Author name: اسيل محمود شاكر السهيل
Supervisor name: قتيبة نبيل نايف القزاز
Specific topic: Statistics
Degree: Doctorate
Language: Arabic
University location: Baghdad
First pages:
Abstract: تعتبر المعولية اداة لتقييم الاداء الوظيفي لاي منتج خلال فترة حياته وتعتمد على ظروف عمل ووقت وبيئة محددة وهي من المستلزمات الاساسية في العملية الانتاجية، وتنبع الاهمية الكبيرة للمعولية كونها تلائم اغلب التطبيقات العملية والمتمثلة بالمعدات والاجهزة العا | The reliability as tool to estimate the work performance of any product during its life cycle, it depends on restricted conditions of work and the time and environment of work, also it considers as essential requirement in the production, the most significant important of reliability represented of being fit for the most of practical applications such as equipment and invalid devices which can fix and get maintenance in case it stopped of work then return it to work again. These devices and equipment consider as correlation between a group of parts or components to form what it is called “system” , there are any kinds of systems classified according to the way that components are connected such as k - out of - n which is ready to work if at least one of k components is working, and “Series system” which is ready to work if all of its components are working , also there is another kind of system its work just in case one of its components is working and this called “Parallel System”. Therefore , the aim of thesis focuses on estimating the reliability of systems (k - out of - n, series and parallel system ) by nonparametric and semi parametric methods using Dirichlet process prior and compare it with reliability of system values by classical methods which is represented by Kernel estimator method , Kaplan - meier estimator method and product limit estimator method to illustrate the quality using statistical indicator Integral Mean Square Error (IMSE) , in additional modified methods. So the simulation procedures to create using different sizes of samples , then applying the best method for Series system on the real data which collected in Al - Mamon factory which belong to general company for plant oil production - Aluminum department the results showed that the reliability function values start decreasing with increasing time in relation to the estimated nonparametric and semi parametric , this means that machines has many invalid because the more invalid in machines cusses to decreasing it reliability

مقارنة بين طرائق تحليل وتنبؤ السلاسل الزمنية وتطبيقها على مبيعات الشركة العامة لتوزيع كهرباء بغداد == Comparative Studies Among The Methods of Analysis And Forecasting Time Series With Application On Electricity Sales In Baghdad City

Author name: اسيل سمير محمد محمود
Supervisor name: عبد المجيد حمزة الناصر
Specific topic: Statistics
Degree: Doctorate
Language: Arabic
University location: Baghdad
First pages:
Abstract: يعد التنبؤ بالسلوك المستقبلي للسلاسل الزمنية من الموضوعات الهامة في العلوم الاحصائية، وذلك للحاجة اليه في مجالات الحياة جميعا، مثل التنبؤ بالحالة الجوية ودرجات الحرارة، حالة السوق والاسعار، تدفق المياه، واستهلاك الطاقة الكهربائية. وقد تزايد الاهتم | Forecasting of future behavior of time series is one of the important subjects in statistical science, because of its need in the different fields of life, like forecasting of weather state and air temperature market state and price water flow consumption electrical power, in the recent years there is an increased interesting in forecasting, and some new techniques like Artificial Neural Networks and Fuzzy Trend Sets. These techniques are able for learning and self - adaptation with any model, and don’t need assumption on the natural of time series. On the other side, the classical forecasting methods like Box - Jenkins method, exponential smoothing and adaptive filtering need certain conditions. A condensed study was done to compare between ordinary methods, namely; Box & Jenkins, ES, and Adaptive Filtering with modern methods namely; ANN, and Fuzzy Trend Set, where some new results are obtained and new method was proposed. A raw data electrical power in Baghdad city is used to perform this comparison through the application of the two programs Statistica and Matlab. From the practical application it found that proposed method gives better and more efficient results than others.

ايجاد التوزيع الثنائي المشترك باعتماد دوال رابطة مختلفة مع تطبيق في المجال الحيوي == Finding Bivirate Distribution By Using Different Copula'S Functions With Application In Biotical Field

Author name: اسماعيل هادي جلوب
Supervisor name: ضوية سلمان حسن الجنابي
Specific topic: Statistics
Degree: Doctorate
Language: Arabic
University location: Baghdad
First pages:
Abstract: تتلخص الدراسة على كيفية ايجاد التوزيع الثنائي الاسي المشترك من خلال دالة الرابطة وقد طبق ذلك على رابطة plackett حيث تم اقتراح رابطة جديدة من التعديل الرياضي الذي تم على تلك الرابطة , حيث تم اجراء المقارنات بين رابطة plackett والرابطة المقترحة والمقدر المع | The limit of our the research we choosing the copula function to finding probability joint distribution and application it on plackett copula to finding exponential joint bivariate distribution. The research introduce the method for obtaining a modified plackett's copula ,and also modification for the estimator of proposed copula function, also using simulation for different values of sample size , all the result and comparison using BAISE,RMSE,AIC,BIC are explained through special tables we show that the results in the suggest copula is better for all cases, We do the practical on suggest copula for the data obtained from central child hospital - ministry of Iraqi health which consist the data about Total Serum Bilrubn (T.S.B) and Park Cell Volume (P.C.V).

مقارنة بين طريقتي SIMEX وLLS لتقدير دالة الانحدار اللامعلمية باستخدام المحاكاة == Comparison Between SIMEX & LLS Methods To Estimation Nonparametric Regression Function Using Simulation

Author name: اسراء سعدون علوان
Supervisor name: دجلة ابراهيم مهدي العزاوي | نذير عباس الشمري
Specific topic: Statistics
Degree: Master
Language: Arabic
University location: Baghdad
First pages:
Abstract: لقد كان من ثمار الانتشار الكبير للحاسوب الالكتروني ولا سيما في العقدين الاخيرين شيوع استخدام الاساليب البيانية في المجالات شتى, ويستعرض هذا البحث اسلوب بياني في التقدير الاحصائي يدعى بتقديرSIMEX باستخدام اسلوب kernel.وتعنــي SIMEX (Simulation - Extrapol | One of the products of large using of computers specially in the last two century is the large using of graphic method in every field, this study consider one of the graphic method in statistical estimation called SIMEX (Simulation - Extrapolation) by using kernel method.With any regression model, three steps then fine the SIMEX estimator : (a) select a finite set of ?’s such as ?={0,0.5,1.0,1.5,2.0} and compute ;(b)fined the average ;(c)extrapolate this estimator back to ?= - 1 ,resulting ,using simulation we compare between SIMEX and LLS (Local linear smoother).And from the simulation’s results we found that the best method is SIMEX when (n<60) specially with Epanchnicov function.

استخدام توزيعي بيتا والاسي في تقدير معالمات انموذج الانحدار الخطي == Use of Beta & Exponential Distributions To Estimate The Parameters of The Linear Regression Model

Author name: اسامة محمد جاسم القصاب
Supervisor name: اموري هادي كاظم الحسناوي
Specific topic: Statistics
Degree: Doctorate
Language: Arabic
University location: Baghdad
First pages:
Abstract: تبقى عملية التقدير لمعلمات انموذج الانحدار من المواضيع المهمة رغم كثرة ما كتب عنها من خلال البحوث والدراسات وهذه الدراسات تختلف باختلاف الاساليب المتبعة في عملية التقدير سواء كان هذا الاسلوب تقليدي او بيزي او تبعا للتوزيعات التي يتم توظيفها في عملية التق | the process of estimating the parameters of regression model , is still still one of the important subjects despite of the large number of papers and studies written in this subject , these studies are differ in techniques followed in the process of estimation , whether they are classic or baysian , or according to the distributions applied in the estimation , and which are available about some of the parameters of regression model.In this thesis , two different distributions are applied ( Beta , Exponential )in estimating different sample sizes and then making a comparison among the classic estimation techniques represented by (OLS) method , and the method of applying one distribution or two (u.d) , and the baysian methods by providing the distributions themselves.By using the simulation technique , results has been obtained to provide the researcher with the image to clarify the best method in the estimation technique.This thesis come in four chapters : The first chapter contains the introduction and the background of the subject.The second chapter contains the theoretical basis of the estimation methods, when one or two distribution are applied in estimation technique whether is the classic or baysian method, it also contains all that related to derivation process to obtains the estimation style.The third chapter contains , a display of the practical side and also a display of the results of the simulation process used to reach to the best techniques of estimation.Finally, the forth chapter contains the conclusions and recommendation as well as future studies.

مقارنة مقدرات بيز القياسية لمعلمة توزيع باريتو باستعمال دوال خسارة مختلفة == A Comparison of Standard Bayes Estimators For Parameter of Paretodistribution Using Different Loss Function

Author name: اخلاص علي حمودي الحديثي
Supervisor name: صباح هادي عبود الجاسم
Specific topic: Statistics
Degree: Master
Language: Arabic
University location: Baghdad
First pages:
Abstract: في هذا البحث تم دراسة مقدرات بيز القياسية لمعلمة توزيع باريتو لاربعة دوال خسارة هي : 1. دالة الخسارة التربيعية Squared Error Loss Function 2. دالة الخسارة التربيعية المعدلة Modified Squared Error Loss Function 3. دالة الخسارة الاسية الخطية Linerar E | In this research was studied the standard Bayes estimators for parameter of Pareto Distribution for the following four loss function : 1 - Squared Error Loss Function. 2 - Modified Squared Error Loss Function. 3 - Linear Exponential Loss Function. 4 - Modified Exponential Loss Function. In the theoretical part of this research was derived two standard Bayes Estimators for the second and the third function As for the standard Bayes estimators for the first and the fourth function it were available in the research on the subject. In the experimental part in this research A simulation approach By Monte - Carlo method is used to comparisons between preference of the fourth estimators for parameter of Pareto Distribution taking in to consideration the two statistical indicators Mean Squared error (MSE) and Mean Absolute percentage error (MAPE) for different samples sizes and under certain conditions demonstrated preference of standard Bayes estimator for each function of these functions also was the verification of the theoretical part on the research in experimental and under certain condition of two standard Bayes estimators for the squared error loss function and Modified linear exponential loss function

طرائق تقدير دالة المخاطرة لتوزيع Quasi Lindely : بحث مقارن مع تطبيق عملي == Comparison of Some Methods For Estimation of Hazard Function of Distribution Quasi Lindley With Application

Author name: احمد علوان صالح
Supervisor name: صباح هادي عبود الجاسم
Specific topic: Statistics
Degree: Master
Language: Arabic
University location: Baghdad
First pages:
Abstract: ان البحوث المتعلقة بامراض الاطفال ومنها امراض الدم تكتسب اهمية بالغة لما تسببه هذه الامراض من زيادة في نسب الوفيات بين الاطفال مما يؤثر سلبا في نمو المجتمعات لان هذه الامراض تستهدف قاعدتها الاساسية والمتمثلة بالطفولة. من المعلوم ان التوزيعات الاحتمالية | The researches on the diseases, including children and the blood diseases is of paramount importance to what caused these diseases from an increase in mortality rates among children, which negatively affects the growth of the communities, because these diseases targeted base of basic and childhood.It is known that the probability distributions is the statistical tool that deal with times of life for patients with diseases that cause of death, and that the issue of determining the statistical distribution of the most flexible in the good compatibility with the data on life times of of people affect the accuracy of the results and specifically estimates for both parameters or a Hazard function , which provides hospital and its staff of doctors, nurses, research centers , important evidence in the medical analysis of these diseases in order to develop methods of treatment and related drugs and medical devices to other medical supplies.In this research was study the of blood leukemia disease problem in the children what caused the disease in the increase in the number of deaths for children with this disease.In this research , review the distribution of properties (Quasi Lindely - QL - ) for the proper matching the practical side data and estimate a risk function using five methods to estimate Maximum Likelihood Method , method of moments, method of L - moment Method of Percentiles Estimators and Standard Bayes Method using Squared Error Loss Function and Logarithmic Loss Function and joint prior distribution noninformative prior using (Jeffrey's formula) also used the method of Lindley Approximation to solving integrals resulting from the use Bayes way to estimate the Hazard function for this distribution.In order to find the best methods of judgment for the purpose of use in the practical side in this research were employed style simulation way (Monte Carlo) and using the Mean squared error (MSE) and the Integral. Mean square Error (IMSE) in order to compare the efficiency of the estimators to function risk was reached through implementation of simulation experiments that Bayes estimator to a Hazard function of distribution (QL) using a logarithmic function loss is the most efficient for small and medium volumes of samples while Maximum Likelihood Method and Method of Percentiles Estimators are better for large samples and at the same efficiency.Finally, in the practical side was used a sample size of data (n = 42) of the children of the deceased because of the disease leukemia blood have been employed estimator Bayes using to estimate the Hazard function loss logarithmic function to these patients. The results showed that the Hazard function of death among children in Iraq function values because of this disease are higher values than necessary health institution looks at this phenomenon and develop sophisticated prevention and treatment and to provide various medical supplies to minimize the seriousness of this disease, which leads to the depletion of human and financial resources, which negatively affects the process of progress of society as well as scientific methods should health institutions raise community awareness of the reasons this the disease for the purpose of avoiding these reasons and by employing various media, particularly newsletters that you know the reasons of the disease and treatment modalities.

استعمال انموذج تجميعي عام لمعلمات الشكل والموقع والقياس في بناء منحنى نمو معياري للاطفال في العراق == Using Generalized Additive Models For Location Scale And Shape To Construct Standardized Growth Curve For Iraq Children

Author name: احمد شهاب احمد
Supervisor name: خلود يوسف خمو
Specific topic: Statistics
Degree: Master
Language: Arabic
University location: Baghdad
First pages:
Abstract: تعد منحنيات النمو المعيارية اداة مهمة في تقييم سلوك النمو البشري خاصة في السنوات المبكرة من عمر الطفل، ويجب ان تبنى بشكل يلبي الهدف منها، وهو تحديد الكيفية التي يجب ان ينمو بها الطفل اذ ان اي انحراف للقياسات البشرية للطفل عن مسار منحنيات النمو نحو الادنى | The growth curves standard is an important tool in the evaluation of the behavior of human growth, especially in the early years of the child's age, and must built to meet the goal of which, Determine how the child must should grow, because any deviation of anthropometric for the child from the path of growth curves towards the minimum or Top necessitates a review of health centers interested in child care because of this change in the behavior of growth is an indication of the possibility of a health problem for the child have a far - reaching impact on his life, and also that the it reflect the level of the general welfare of the community posed as a result of human needs nutrition, health and development of this society, and all the developed countries of the world has its own growth curves commensurate with the ethnic diversity and its population, and Iraq , similar to these countries need independent growth curves achieve their desired purpose and it puts a step in the path of these countries. This was the goal of research is building growth curves standard for the children of Iraq under sixth to indicator of weight, height and body mass index against age to each sex in order to take advantage of child - care institutions and adopt them to assess the growth path of the child right in the most important stages of the growth of an early childhood. The growth curves consists of percentiles line called (Centiles) reflect different levels of growth represent the behavior of a specific and accurate so they need to statistical methods and data in order to achieve this requirement , so it was chosen as a model statistical claims GAMLSS from a wide range of statistical methods characterized by the allowed a wide group of distributions treated skew and kurtosis of growth data, in addition to the flexible methods of smoothing Treat the unstationary in the data, it based on building a model special for each standard growth using criteria to choose as the first step by choosing the appropriate distribution of the data to impose the parameters represent a nonparametric smooth functions of independent variable often takes age, the second step is to choose the appropriate degree of smoothing to this functions.That the building of growth curves based on a sample taken from MICS4 from the survey of children under the age of six who are subject matter and carried out by the Central Statistics organization in 2011, and after processing the data removed cases of children who were exposed to health conditions or nutritional possible affect the potential genetic growth Physiological and thus give wrong

المقارنة بين بعض طرائق تقدير انموذج انحدار اللوجستك والطرائـق الحصـينـة للتجارب الحياتية ذات الاستجابة الثنائية باستخدام اسلوب المحاكاة == Al - Comparison Between Some Estimated Methods of Logistic Regression Models And Robust Methods For The Bioassays of The Quantal Response By Using Simulation Procedure

Author name: احمد ذياب احمد العزاوي
Supervisor name: دجلة ابراهيم مهدي العزاوي
Specific topic: Statistics
Degree: Master
Language: Arabic
University location: Baghdad
First pages:
Abstract: الحمد لله والصلاة والسلام على رسول الله سيدنا محمد (صلى الله عليه وسلم) وعلى اله وصحبه وسلم اما بعد... تناول البحث استخدام انموذج انحدار اللوجستك في التجارب الحياتية باعتباره موضوعا على قدر من الاهمية , وان هناك شروط يجب ان تتوفر لغرض اجراء التحليل بال | This study deals with using the logistic regression model in the bioassay which is considered an important topic and there must be assumption which should be satisfied in order to carry out analysis in the classical methods ( Weighted least squares method and Maximum likelihood method ) as success normal distribution assumption for errors , when one assumption of normal distribution is fail or outlier in data this lead to taking the fail decision concerning the problem needed so be studied.Here lies the importance of applying robust methods (M method and R method ) in the bioassay of the quantal response because the Robust estimated has little response and little effects of outlier.To state the contents of this thesis it was divided into four chapters. The first chapter included the introduction and the aim of this research work. The second chapter included the theoretical part where we stated the estimated methods for the logistic regression model and the Robust methods. The third chapter went through the practical part of this research work. Finally Chapter four went through the conclusions and recommendations of this research work. As well as the future studies, which have been proposed regarding this research. of the most important results the study reached is the efficient M method and R1 method for two robust in estimator the parameters dose model of the quantal response

مقارنة دوال كثافة الطيف للسلاسل الزمنية غير المستقرة لحجوم عينات غير متساوية مع تطبيق عملي == Comparing Spectral Densities of Non - Stationary of Time Series With Unequal Sample Sizes

Author name: احلام حنش كاطع
Supervisor name: لميعة باقر جواد الجواد
Specific topic: Statistics
Degree: Doctorate
Language: Arabic
University location: Baghdad
First pages:
Abstract: في هذه الاطروحة تم تقدير المسافة بين اي دالتي كثافة طيف لسلسلتين زمنيتين غير متساويتين في الطول مع ادخال عامل الزمن والتردد ومن ثم اختبار التشابه والاختلاف وفق الاختبار الاحصائي (Nievau - ?) من خلال المقارنة بين دوال كثافة الطيف لسلاسل زمنية شبه مستقرة ال | In this thesis the distance between any two spectrum density functions not equals in the length estimated with interring time and frequency factor then testing the similarity and difference according to statistical test (Nievau - ?) through the comparison among spectrum density functions for non - stationary time series and have a diffirent length (sizes). There are many methods for estimating spectral density functions for non - stationary time series, Therefore we study three different methods which are an important methods where every method holds more characteristics of spectral density functions which are : Evolutionary spectrum method, Wigner - Ville spectrum method and Short - time periodogram method. A forth method suggested depends on shrinkage principle called Shrinkage method which is combines the characteristics of these methods and with a deferent weights p_(1 ,) p_2 where the mathematical derivation for computing weights to the past methods and finding the best weights that gives the smallest MSE has been done.Then a comparison among these four methods to select the best method for applicant it in Oral part using (MAPE)criteria. A simulation experiment conducted on a semi - stationary time series which is a special case of non - stationary time series that follows elated process with the from : x(t)=c(t)x_t^0 Where : C(t) is a function depends on t only, x(t) is a stationary time series follows ARMA(p,q) models with different parameters and different sample size, The result of simulation shows that suggested method (shrinkage method) for spectral density is the best in all of models and sample sizetherefore the best method in estimation is used in oral part to estimating the spectral density concentration of airborne particles (TSP) of three stations (Jaderyah, Andalus, Al - Alawi ) in Baghdad province contains the interval ( 2005 - 2011) measured monthly and this series are different in length, the distance between any tow series are estimated then tested The result show that there are no convergence between density function for the spectrums of these three series that’s mean there are a different in air pollution for the three regions according to its nature

اختبارات التكامل الكسري في نماذج ARIMA == Tests of Fractional Integration In Models ARIMA

Author name: احلام حنش كاطع
Supervisor name: لميعة باقر جواد الجواد
Specific topic: Statistics
Degree: Master
Language: Arabic
University location: Baghdad
First pages:
Abstract: توجد انواع من العمليات العشوائية المستقرة لا نستطيع ان نعدها كنماذج من الاوساط المتحركة او الانحدار الذاتي اذ انها تحتوي عل خصائص هذين النوعين (انحدار ذاتي - اوساط متحركة) فمثل هــذه العمليات تسمـى بالنماذج المختلطة ويرمز لها بـ (ARMA(p, q)) ولكي تتوفر ال | There are many types of stationary stochastic processes that can’t be considered as models of moving average or autoregressive, because they have the characteristics of these two kinds : (Autoregressive - Moving average). These processes are called mixed models and referred to as (ARMA (p, q)). In order that these models have the stability, the roots of equation must equal zero , outside the unit circle and also for the Inevitability, the roots of equation must equal zero , outside the unit circle. These models may be non - stationary in themselves but they will be stationary after many transformations or differences, so the models which explains this process will be different from the original, because it must contain those differences that have been done on the original models. These stationary models are called ARIMA, and the differences may be inter numbers or fractional numbers, then, the differences will be fractional numbers ranged between [0.5 , - 0.5] , and the model is called ARFIMA or what is called as fractional integration, and (d) represents the parameter of the fractional differences. In this study, three methods have been applied to test the non stationary models of the fractional integration (ARFIMA). One of the common test used is that which is based on the periodogram regression suggested by GPH, whereas LO suggests another test modified from the classical test which is known as modified rescaled range (MRR). A third test has been presented which adopts the idea of lagrang multiple which is known as : (LM). These tests have been applied in four models; AR, MA, ARCH and ARFIMA. The way of simulation and building programs using Visual basic (V. B) has been employed the percentages of the times of rejection have been gained out of 1000 frequencies for each method of the test, for each parameter and for more then one sample. The fractional integration parameter of the first test GPH has been compared with table (t), because variance is unknown, as to the second test MRR, the value (R/S) is compared with table LO, the third test LM is compared with table Z.
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