Show: 25 50 75 100 Results

Search results: 25 out of 157

تشخيص وفحص مدى الملاءمة لنماذج السلاسل الزمنية المختلطة ذات الرتب الدنيا == Identification And Diagnostic Checking For Low Order Mixed Models

Author name: عبيد محمود محسن الزوبعي
Supervisor name: عبد المجيد حمزة الناصر
Specific topic: Statistics
Degree: Doctorate
Language: Arabic
University location: Baghdad
First pages:
Abstract: تمثل الهدف ببحث مرحلتي التشخيص Identification وفحص مدى الملاءمة Diagnostic checking للنماذج المختلطة ARMA ذات الرتب الدنيا في مجال الزمن Time Domain وفي مجال التكرار Frequency Domain والمقارنة بين ادوات التشخيص ومعايير اختيار الرتبة واختبارات فحص مدى المل | The aim of this work is to study the two stages of identification and diagnostic checking of mixed models (ARMA) with low orders of time domain and frequency domain.The methodology of research had tackled in balanced way both the theoretical part (by using statistical theory) and experimental part (by using simulation). The thesis consisted of five chapters in addition to introduction. The first chapter contained the basic concepts of time series, stationary, mixed models with low orders and analysis tools for time domain and frequency domain.The second chapter included the identification stage as it contained the identification tools and selection criteria for models order.Also it included asggestion for two new methods of identification and anew criterion for order determination. The third chapter tackled the diagnostic checking by using a group of tests depending on time domain and frequency domain.Also it included viewing of some other aspects in time series analysis in order to open new avenues which could be traded by other researchers.The fourth chapter contained the experimental part by applying what had been depicted in previous chapters on mixed models (ARMA(1,1)), (ARMA(1,0)) and (ARMA(0,1)) and then to find out comparisions between identification tools, order selection criteria and diagnostic checking tests through giving different values of the parameters [?1,?1] and for different sizes of series and by iterating the experiments (1000) times.It had been arrived at some conclusions and recommendations which were consisting the fifth chapter

المويجات الهندسية المكيفة وتطبيقاتها في ازالة التشويش للصور الرقمية == Adaptive Geometrical Wavelets And Their Applications In Digital Image De - Noising

Author name: عامر محمد نوري المهداوي
Supervisor name: ظافر حسين رشيد النجار
Specific topic: Statistics
Degree: Doctorate
Language: Arabic
University location: Baghdad
First pages:
Abstract: تختلف الاهمية النسبية للمعلومات المرئية المحتواة في الصور. اذ ان البحوث الحديثة في فسلجة الرؤية اثبتت بان الدماغ البشري يتحسس لحواف مكونات الصورة بالدرجة الاولى، اما الانسجة فتاتي بالدرجة الثانية من الاهمية. دفع هذا الامر العديد من الباحثين في حقل المعالج | The importance of visual information contains in images are relatively deferent. Recent researches in psychology of vision have proven that human brain senses the edges of image objects in the first order, where image textures comes in the second order of importance. This problem had motivated researchers in the field of image processing towards finding new efficient methods that work on eliminating less important visual information which gives as a result a brief description containing the most important information. This description serves two domains : the first one is image compression, where it is possible to reduce the amount of data used in representation, which helps in reducing the required transmission time and also needs less storage size. The second one is image denoising, by reducing the importance of noisy data which helps in eliminating the noise, or at least compress its effect.Recently, it has become evident that separable transforms, such as wavelets, are not necessarily best suited for image representation due to their disability of catching line discontinuities that represent the objects edges, which make them unsuitable in giving adequate description for deferent geometrical shapes of these edges. This led to the appearance of the geometrical wavelets which has been proven its superior to nearly all of the classical wavelets in giving higher specific approximations and much more economical in data size of the image. These functions are non - separable and they are divided into two parts : adaptive functions and non - adaptive functions.This dissertation focuses on studying the first and most important function of the family of adaptive geometrical wavelets functions, the one called wedgelets, in addition to propose generalizations to it in order to make it more flexible in catching deferent curved shapes of image edges, which improves its performance in providing much more specific approximations depending on less number of coefficients. This work emphasizes basically in image denoising. And in order to increase the applicable importance of these functions, it has been suggested two methods to estimate the noise level that effects the image, and eventually choosing the best approximation according to this estimation.Finally, a comparison is made between the proposed approximation methods and the classical ones by applying on several tested images that have deferent properties, through the simulation of exposing them with deferent levels of noise. The results of this comparison shows good size of improvement in the performance achieved by the addition of these proposed functions.

استعمال اشجار الانحدار التصنيفية والانحدار اللوجستي في تقدير انموذج تجميعي والمقارنة بينهما مع تطبيق عملي == Using Classification Regression Trees And Logistic Regression To Estimate Additive Model Comparison With Application

Author name: سهاد احمد احمد
Supervisor name: عمر عبد المحسن علي القيسي
Specific topic: Statistics
Degree: Doctorate
Language: Arabic
University location: Baghdad
First pages:
Abstract: تعاني بعض الظواهر من وجود حالة اضطراب في بياناتها بالاضافة الى صعوبة صياغتها وخصوصا مع وجود عدم وضوح في استجابتها، او لكثرة الاختلافات الجوهرية التي تعتري الوحدات التجريبية التي تم اخذ هذه البيانات منها. فعندما تزداد المجاميع لمجتمع ما, لا يمكن اعتبار ذل | Often suffer phenomena and there is disturbances in their data as well as the difficulty of formulation, especially with a lack of clarity in the response, or the large number of essential differences plaguing the experimental units that have been taking this data from them. When growing groups of a population, it can't be regarded as a homogeneous population is increasing because the dispersion between the experimental units in response to that population as well as the error will also be increasingly difficult to build a model of that population.So there was a need to include an estimation method on the classification or underlying discrimination for these pilot units using discrimination or create segments for each item of these pilot units in the hope of controlling their responses and make it more in line style.Has been resorting to the use of the method of a modern and flexible classification is based on the neighborhoods between the views represented by the response variable by classification regression trees : CART. It was the use bayesian approach and the promise of features indicative of regression analysis model classification tree to take advantage of the above information by, and collect trees for explanatory variables are all together and at every stage fork on the other hand, represented the bayesian classification regression trees : BART.In view of the development in the field of computers and taking the principle of the integration of science it has been found that modern algorithms used in the field of Computer Science swarm of birds and other originally illustrated algorithm for the purposes of technology pertaining to distinguish between images or vibrational radio, etc., can be harnessed to serve the knowledge of statistics, which is based Turn on the information production and to achieve success in it. So is the use of genetic algorithm and submit a proposal by modified genetic algorithm, in addition to C4.5 and ID3 algorithms. And without losing the generality has been used as a tool of logistic analysis as important tool.It was a whole performance along with an estimate of the general additive model method of classification of all the methods mentioned in the above. Fitted model as modern and flexible overcomes curse of dimensionality that may occur most modern phenomena of the times when their data analysis.It was the use of simulated samples of different sizes (200, 400, 600) with (1000) replicates. The application was performed on patients with diabetes data for those aged (15) years and below are taken from the sample size (200) was withdrawn from the children hospital/ Al - Eskan/ Baghdad.As proof of the goodness of classification has been using the misclassification error, and as proof of the goodness of estimation has been using the root mean squares error.Was reached important conclusions through a process of differentiation among the six methods above, the superiority of the Classification and Regression Trees Algorithm (CART) is the best in terms of the results that has been reached in empirical side, when proposed Genetic Algorithm is the best in terms of the results that has been reached in applied side.

بعض المقدرات الحصينة لقدرة الطيف وفق الانموذج المختلط ARMA مع تطبيق عملي == Some Robust Estimators For Power Spectrum According To The Arma Models With Application

Author name: سحر طارق محمود الرحيم
Supervisor name: عبد المجيد حمزة الناصر
Specific topic: Statistics
Degree: Doctorate
Language: Arabic
University location: Baghdad
First pages:
Abstract: تهدف الاطروحة ايجاد افضل مقدر(التقدير الامثل) لدرجة ارتداد الانموذج المختلط ARMA ذي الدرجات المتدنية لقدرة الطيف Power Spectrum والحصول على امثلية التنبؤ، اذ ان مشكلة الاطروحة تكمن في خطا اعتماد اساليب تقدير درجة الارتداد قبل اطفاء اثر الشواذ التجميعية ( | The Aim of The thesis is finding the best estimator (optimal estimate) the degree of rebound mixed model ARMA with low scores to Power Spectrum and get optimizing forecasting, As the problem of the thesis lies the mistake of adopting methods of estimating rebound degree before extinguishing (AO) Outliers (additives Values) in an estimate operation based on data series without getting rid of the effect of the presence of Outliers. According to This thesis addressing the Existence of the Outliers, in particular, (AO) Outliers after addressing the existence of Outliers, then starting estimate the optimization for a rebound.When interest in Robust estimates we must identify the time series contaminated Outliers with a certain probability models is defined due to lack of stability in addition to the difficulty of knowing specimen probabilistic it appears at first paragraph leap suddenly are called stereotypes Bahawaz Innovation Outlier, late to be the behavior of independent gay behavior values the other called Bahawaz aggregate Additive Outliers.When interest in estimates fortified must identify the time series contaminated Outliers with a certain probability models Unlimited Parameters is defined due to lack of Stationarity in addition to the difficulty of knowing probabilistic model ,it appears at first paragraph sudden leap are called Innovation Outlier, or be an independent behavior of other values called Additive Outliers.Shows the experimental side of the Thiess through a standard MSE, MAPE preference of Robust method on the Unrobes for all sample sizes and for all primary parameters assumed values, as well as for all default frequencies values (Wi), have an adverse impact in terms of efficiency when models ARMA (0,1), ARMA ( 0.2), and very slight variation when the model ARMA (1,1) the impact of outliers and the supposed frequencies (w) = [1/4, 1 / 3.3, 1 / 2.5, ½] small.The nature of the electrical signal surveyed of heart (ECG - Electrocardiogram) a vital signal , unstable and the form of Signal spectrum reflects the Performance of the human heart muscle and its health.is random changes sharp and irregular in time series represents the work of the heart of a natural person (without straining) include what is known Outliers caused by its actual nature not the result of errors in the measurement or the register, which makes them do not follow a particular distribution, led to the difficulty of conducting Assessments for Power spectrum according to the traditional methods of estimation that assumes distributed statistically,In addition to that the data generation processes require the availability of basic assumptions is inconsistent with the nature of the Heart signal ECG, and to minimize or reduce these assumptions adopted by the simulation approach often leads to unrealistic and far from the real system results and establishes a breakthrough for good properties of these estimates that we have made it necessary to adopt the idea of Robust estimates (M - estimate) in accordance with the Robust functions (Huber, Hample, Tukey, Andrew) in addition to the method of maximum likelihood Mle according to restricted simulations in the practical side, which serves as a purification process or soften the Estimators resulting from follow of statistical estimation methods on real data to determine the best estimators of Power spectrum and the search for the best Model and section distribution , and then apply the result of a trade - offs in according to indicator the indirect transition of the speed of the signal (?/S2) between the Estimation functions and Distributions on eight of combinations of Mixed model ARMA (p, q) and estimating MSE, RMSE and selecting the optimum combination which is ARMA (2,2) with Extreem value distribution and with Hampel function at section 200, which amounted to (MSE = 0.000109).

مقارنة بعض الطرائق المعلمية واللامعلمية لبعض تصاميم القياسات المكررة == A Comparisoin of Some Parametric And Nonparametric Methods For Some Repeated Measures Designs

Author name: سجى محمد حسين علي الهاشمي
Supervisor name: ظافر حسين رشيد النجار
Specific topic: Statistics
Degree: Doctorate
Language: Arabic
University location: Baghdad
First pages:
Abstract: في الكثيرمن الدراسات الطبية والتربوية والسيكولوجية (علم النفس)وعلم الاجتماع نشاهد بان المفردات (subjects) تتكرر تحت مختلف الشروط التجريبية((conditions والتي تسمى بالمعالجات (treatments) وان البيانات المتجمعة من مختلف الوحدات التجريبية تفترض لان تكون مستقل | In many medical , educational , psychology and sociology studies we find that the same subjects repeated under different experimental conditions which called treatments. The collected data from different experimental units suppose to be independent while the observation for the same experimental units will be dependent. The term repeated measures designs is called for this type of data in which the response for every experimental units or subjects is tested or measured under a number of different experimental conditions. Our attention will be on the case of a univariate response variable. There are many procedures for testing the null hypothesis that there is no treatments effects, depends on the number of treatments. either the same subjects are tested under two treatments or tested under three treatments or more. The aim of this study is comparing the tests for nonparametric and parametric methods of repeated measures designs for two treatments through applying the tests on true experiments data. and comparing the tests for nonparametric and parametric methods for three treatments or more, which included two designs which are the complete randomize block design when the ANOVA conditions are satisfied. And the One - way generalized repeated measures model when does not assume specified form of the variance - covariance matrix.Simulation procedures are used in order to compare probability of type one error and power of the test for all methods. In addition , the researcher presented the suggested methods and analyzing the results by comparing them with the other methods for the mentioned designs.

طرائـــق بيــز فــي تحليــل نمــوذج القياس الاقتصادي المكاني مع تطبيق عملي == Bayes Methods In Analyzing Spatial Econometrics Model With Practical Application

Author name: سامي غني خضير عطره
Supervisor name: خالد ضاري عباس الطائي
Specific topic: Statistics
Degree: Doctorate
Language: Arabic
University location: Baghdad
First pages:
Abstract: ان الخاصية الاساسية لتمييز البيانات المكانية عن بيانات السلاسل الزمنية هي الترتيب المكاني للمشاهدات , وعينات البيانات المكانية تمثل مشاهدات ترتبط بنقاط او مواقع وتتميز هذه البيانات بان ارتباطها يضعف كلما بعدت المسافة وكذلك تتميز بتدرج المكان (( المناطقية | The main property to differentiate the spatial data from time series data is the spatial arrangement of observations and the samples of spatial data represent observations related to points or locations these data are distinguished with the weakness of their connection each time the distance getting far away and the place graduation (location)on the spatial relations of observations are represented in matrix named spatial weights matrix. The spatial econometrics is used in following up the spatial effects like the spatial dependence of observations in different points of place, and spatial heterogeneity arising from relations or parameters model that change with sample data in each time we move within the place , those two points have been neglected in traditional econometrics because of their sinconsistency of statistical assumptions and when taking those spatial effects into consideration ,the statistical influence will be of high efficiency. On the contrary, ignoring these effects will lead to loss the information and will not be as efficient as the dependant sample.Because of the difficulty of deriving the posterior function (on which the Bayesian inference depends) up on applying the Bayesian methods especially in cases that the number of probable models is very large as computing the posterior functions for all these samples requires integration for large dimensions functions which is very difficult Mathematically or inapplicable that requires proper methods can deal with such cases like Gibbs and Metropolis - Hastings sampling by analyzing the posterior distribution to number of conditional distributions for each parameter in the model and then the simplicity of inference for each parameter in the model.The matrix of spatial weights is built by registering the contiguity relations for each location with others in a matrix row (w?) and given (1) if there is a relation between two locations (wij=1) and zero, if it doesn’t (wij=0)as i and j refer to the rows and columns in sequence. For making the summation of each row in the matrix w? equal to 1 , the elements of matrix will be calculated according to the proportion : wij/ ?wij and i=1,2…,n j=1 Consequently, we will get the adjusted matrix W.The practical side was focused on the counting of spatial autoregressive model parameters, and these parameters is the vector ? and it is an ordinary regression parameters vector, and error variance parameter (?2) , and the most important of them is a countig of the parameter (?) which is represent spatial dependance parameter.In order to show the role of the spatial, the practical side included taking the real population for childrens between(1 - 19) year, that had iron deficiency anemia (due to from iron deficiency) that admitted to children’s hospitals in Kurkh district of Baghdad (which had been divided into five geographic regions) for 2010. We have suggested that computing the elements in the adjusted matrix to be on basis of the actual length proportion of the joint borders among different locations that lead to get the accurate estimated value of spatial dependence parameter، where value result of spatial dependence parameter (?) was (0.43) when use Metropolis - Hastings sampling method while value of this parameter when use spatial outoregressive function and by using the adjusted matrix was( 0.57) and value of this parameter when use the same regression function but by using the suggested matrix was (0.85).

مقدرات بيز لدالة المعولية الضبابية للتوزيع الاسي باستخدام المحاكاة مع تطبيقها على الشركة العامة للصناعات الكهربائية == The Fuzzy Reliability Function Bayes Estimators For Exponential Distribution Using The Simulation With It Is Application On The State Company For Elictrical Industeries

Author name: زينة ياوز عبد القادر اوجي
Supervisor name: عماد حازم عبودي
Specific topic: Statistics
Degree: Doctorate
Language: Arabic
University location: Baghdad
First pages:
Abstract: يدرس البحث الضبابية والتي مفهومها ان كل قيمة تقع ضمن فترة معينة،ونعتمد في تحديد حدود هذه الفترة على الخبرات السابقة حول موضوع الظاهرة المدروسة.وفي بعض الاحيان يصعب تحديد هذه الفترة ونتعامل مع القيمة الضبابية وما حولها من القيم القريبة دون الاعتماد على ا | This paper concerned with studying the fuzzy which means that each value is within specific period and to determinate the limits of this period depends on previous expertises about the studies phenomena subject.Some times it is difficult to determine this stage or period ,in this case we deal with the fuzzy values and other proximate ones without depending on previous expertises ,because they are not available or because of te differences in points of researches,view about the determination of minimum and maxmum restriction for there values.Through this research we will treat fuzzy lifetime data that each value does not have minimum and maximum limitation which enable us to appoint the sutable belonging degrees but all lifetime data have minimum restriction which represent the begininning life time , and maximum one that represents the end of lifetime And by using membership function of Ching to determing a membership function for those data , This paper discussed two procedures to estimate the fuzzy reliability ,Bayes procedure that includes the following : 1 - Sample data are fuzzy and the prior distribution for parameter includes an unfuzzy parameter.2 - Sample data are unfuzzy and the prior distribution for parameter includes an unfuzzy parameter. 3 - Sample data are fuzzy and the prior distribution for parameter includes a fuzzy parameter. 4 - Sample data are unfuzzy and the prior distribution for parameter includes an unfuzzy parameter And FRDP (Fuzzy Reliability Definition Procedure) that uses component trapezium method,to find numerical integration ,by using the Exponential distribution form for sample data,and Gama distribution for the prier distribution for the parameter of Exponential distribution ,and four value for sample size.And depending on the results that have been conducted in the experimental side ,it is shown that bayes is the best in estimating the fuzzy reliability when the fuzzy sample data have membership degree equal to 0.1for samples of small sizes. When the failure times average value is bigger than one ,so Bayes is the best in estimating the fuzzy reliability for small samples sizes,and FRDP is the best in estimating the fuzzy reliability for sizes of big samples The data which have been taken from the state company for electrical industries of foundation machine Toshiba are used as well after bayes method and FRDP method are applied to estimate the fuzzy reliability,it is noticed that results of both the applied and experimental side are th

استعمال اسلوب بيز لتقدير منظومة المعادلات الانية في حالة المتغير الداخلي مصنف ثنائيا مع تطبيق عملي == Using Bayesian Approach To Estimate The Simultaneous Equations System In Case The Endogenous Variable Is Classified Binary With Application

Author name: ريسان عبد الامام زعلان
Supervisor name: محمد صادق عبد الرزاق الدوري
Specific topic: Statistics
Degree: Doctorate
Language: Arabic
University location: Baghdad
First pages:
Abstract: ان عملية التقدير لمعلمات انموذج المعادلات الانية بالطريقة التقليدية من المواضيع المهمة والتي كتب عنها الكثير من البحوث والدراسات وهذه البحوث تختلف باختلاف الاساليب المتبعة في عملية التقدير الا ان التقدير بالطرق البيزية لهذه المعادلات وخصوصا عندما يكون ال | The process of estimation of parameters of the following equations has been done by the traditional method and being considered as an important subject. Many researches and books have been written about the subject and these researchers are different from one to another depended on the methods followed up. But the estimation with Bayesian methods for these equations , especially when the internal variables (classified binary ) being considered one of the subjects that have not been researched greatly. Thus , the researcher has tried to shed light on some methods of Simultaneous equations in case of binary variable by using the classic method and Bayesian method , along with a suggested way that being applied on the samples of the relationship between blood pressure and psychological pressure. The researcher has used the classic method and considered it as raw information for using the method of Bayesian in estimating the Simultaneous equations system. It has been compared between the classic method and Bayesian method and also methods of Bayesian with the suggested method according to the measurement of ( Mse) for specifying the better method for estimation. Problems have been specified lying in non - functionalizing the former information about the parameters in the process of estimation by using the known traditional methods and that lead to the less efficiency if not using it. Thus , it should resort to other methods as method of tradition , The goal of the study is to know the mutual interaction between the blood pressure and psychological pressure and comparing the traditional and Bayesian method in the estimation of Simultaneous equations of internal variable , classified binary by using many methods for Bayesian estimation with the suggested method for getting to estimations that are more close to values of the real parameters. it has been reached to many results ,most of which is the Bayesian method and suggested method that have been better in estimation than the classic method, besides there are mutual effects between blood pressure and psychological pressure and the most losing functions in estimation which is the " Q losing function"

تشخيص وتقدير دالة الانحدار اللامعلمي للبيانات المزدوجة في حالة عدم تحقق بعض فرضياته == The Diagnosis And The Estimation of The Nonparametric Regression Function of The Panal Data In Case Some of Its Hypotheses Are Not Verified

Author name: دريد حسين بدر
Supervisor name: ظافر حسين رشيد النجار
Specific topic: Statistics
Degree: Doctorate
Language: Arabic
University location: Baghdad
First pages:
Abstract: اكتسبت نماذج البيانات المزدوجة اهتماما بالغا وخاصة في الدراسات الاقتصادية والطبية والمالية لانها تاخذ في الاعتبار اثر التغير في الزمن وكذلك اثر التغير في المشاهدات المقطعية على حد سواء في بيانات عينة الدراسة، فضلا عن وصف البيانات من خلال تقدير الانموذج ا | Panel data models have gained a great importance especially in economic, medical, epidemic and financial studies. Because these models take into consideration the impact of the change in time, the impact of the change in sectional views alike inherent in data of a study sample, in addition to describing data through Estimation of the appropriate model. In this thesis, we address the use of method of nonparametric regression in diagnosing and Estimation a model of panel data , as there are specific assumptions related to vector of random errors are not verified. This is because we are going to talk about a nonparametric problem and existence of Heteroscedasiticity and Auto correlated errors which make the process of Estimation wrong, or sometimes not possible. A model has been diagnosed through disclosing all of the problem of Heteroscedasiticity through the use of test (1996) (Zheng) and the problem of Auto correlation by suing test (2013) (Su and Lu). It has been indicated through handling a Nonparametric Hausman Test that the final model adequate for research data is Nonparametric Panel Data Model with Random Effects. Thus, finding Nonparametric Estimator has been tackled through dealing with each problem individually alongside with addressing methods of choosing the smoothing Bandwidth of the model of Random Effects. In case of correlated errors for all techniques of Nonparametric Regression, there are methods to deal with this problem, however all of the said depends critically on addressing estimation methods reliant on finding the choice of an optimal smoothing Bandwidth using more accurate standard until the removal of error process to attain an edited smoothing Bandwidth , of any correlation, is achieved. Then, we could Estimation a model by using Estimation methods. In case of Heteroscedastisity, treatment could be achieved through determining weight by Kernel Estimator, then to be used for the exclusion of the effects of Heteroscedasticity in the study variables through using estimation methods and provision of proposals for classic Nonparametric methods. The formulation of simulated experiments of used models and verification of performance of traditional and proposed methods, for all sample sizes and three levels of standard deviation trough the use of (RAMSE) standard, have been carried out in this thesis. One of the most significant objectives of this study is the selection of the best Estimation method produced by simulation through applying it on a group of balanced Panel Data (longitudinal). This could be conducted through carrying out a practical application to state the effect of the role of gross domestic product on fixed market prices measured in a US Dollar (x) in the state budget measured in millions US Dollars (y) for the period (2003 - 2015). This could be approached through depending on genuine data related to general budget for the Arab States measured by millions US Dollars. The gross domestic product has been focused on since it is the most important economic variable that impacts the budget, as an explanatory variable according to the viewpoint of the competent people for the period (2003 - 2015). The main conclusion in the experimental side is a clear preference in absolute terms to the fortified proposal of Least Square Support Vector Machine for Regression by using an (MGCV) standard on other used Estimation methods. This is in case existence of Auto Correlation as well as provision of a verified proposal for Propose (LCNE), relying on a Span, a selection standard, on other used Estimation methods in case existence of Hetroscedasticity, of all sample sizes, all cases and three levels of three standard deviation. As to practical side, an appropriate model has been diagnosed. Also, compatibility of the best method has been proven in the experimental side alongside with practical one, and the most appropriate for a model by using (RAMSE) standard

مقارنة اساليب بيز مع طرائق اخرى لتقدير منحنى الانحدار اللامعلمي == A Comparison of Bayesian Approaches With Other Methods For Estimating Nonparametric Regression Curve

Author name: خلود يوسف خمو يوسف
Supervisor name: ظافر حسين رشيد النجار
Specific topic: Statistics
Degree: Doctorate
Language: Arabic
University location: Baghdad
First pages:
Abstract: لقد شهدت طرائق الانحدار اللامعلمي اهتماما ملحوظا في السنوات الاخيرة كان السبب في ذلك هو ان التفكير المعلمي الصرف المستخدم في تقدير منحنى الانحدار لا يتوافق مع المرونة في تحليل البيانات.ومع التطور المنجز في اجهزة الحواسيب من الناحية المادية وكذلك انجاز | In recent years, too many considerations have been given for the Nonparametric Regression methods. This is for the reason that the concept of pure parametric; used for the estimation of Regression curve, does not cope well with the flexibility needed for data analysis.With the progress made in computer machines, in terms of economy and running performance, it has become possible to develop many of Nonparametric Regression methods theoretically. Though many of these are still under perfection, and facing a number of problems.Hence we see the importance of focusing on methods related to smoothing of Nonparametric Regression functions. This is for the purpose of producing the best methods convenient for various models. And for the Distribution Random error, in its two cases; Normal and Contaminated. Thus, the most important purpose of the research, is to find what the studies so far, have offered in the field of Nonparametric Regression. Also to find alternative or modified methods; which are reliable for the treatment of conditions of failure regarding the methods in use, as well as to alleviate the complexity of some methods, especially those related to Bayesian procedures.One of the most outstanding aims of the research focuses on the study of Nonparametric Regression using Bayesian variable selection. This suggests a modified technique to be reliable and of less complexity than the original one.Amongst the other research intentions, when data are contaminated with outliers, is to explore the Robust Nonparametric Regression, using Bayesian variable selection method. Also to suggest a modified Bayesian method; resistant to outliers, and of less complexity than before transformation. As well as offering suggested methods for Robust Nonparametric Regression. This is of the feature of having less sensitivity towards outliers and reliable in comparison to very few techniques supplied with robustness, as the Bayesian approach.A simulation model has been performed with different distributions, for the random error and for a number of models.To verify the performance of such methods, many criteria have been carried out.To satisfy the purpose of this research, the study has been divided into five chapters. Chapter I consists of an introduction, the problem under research, its importance and purposes. It also covers a literature survey. Chapter II covers methods for smoothing Nonparametric Regression. While chapter III is devoted for Nonparametric Regression and Robust Nonparametric Regression using Bayesian variable selection method. Also in this chapter are details of the suggested methods. Then chapter IV implements the experimental part of the study. Finally chapter V comprises the conclusions and suggestions that the research has recommended. As well as the future studies, which have been proposed regarding this research.

مقارنة طرائق تقدير دالة المعولية للتوزيع الاسي الخليط مع تطبيق عملي == Comprastion Between Methots Estimator Reliability Function of Of A Mixture Exponential Distribution With A Practical Application

Author name: خضر نصيف جاسم البياتي
Supervisor name: عبد المجيد حمزة الناصر
Specific topic: Statistics
Degree: Doctorate
Language: Arabic
University location: Baghdad
First pages:
Abstract: ان الاهتمام المتزايد في دراسة نماذج الفشل جاء نتيجة للدور الذي تضطلع به نظريه المعوليه ودالة الاخفاق بالتعامل مع الاعمار لدراسة ومعرفه سلوك اوقات الفشل في الزمن اللاحق, وتعتبر المعولية احد المقاييس للتعبيرعن اداء اي مفرد او نظام لفترة قادمة لذلك تعد المعو | Reliability theory and Hazard function have played a great role in the rapid interest in the study of failure models. These theories deal with the study of ages to investigate and study the behavior failure time at posterior time. Reliability theory is one of those standards that show the performances of any unite for an expected period of time. It is also considered an indicator for future planning.Accordingly, reliability theory is adopted to study and analyze behavior of failures and the factors behind such failures. To achieve this, the parameter estimators of failure models, with good prosperities and efficiency, are required to count the reliability estimation. Therefore, it is of keen significance to study the methods and techniques for getting the parameter estimators of failure including the parameter estimations of a mixture failure model. These estimations have a great role in reproducing complex cases of non - homogeneous populations. Like the importance of the normal distribution for biological studies, the exponential model is considered of a great significance for the study of failure models.The study aims to estimate the reliability function by employing various methods to estimate the model parameter exponential mixture. To achieve this objective, this study is divided into four chapters. Chapter I shows the introduction and the literature review. Chapter II defines some key concepts of the topic; it also presents the theoretical framework for the employed methods of estimation for a number of parameter estimator method’s complete sample of a mixture of two exponential distributions with different two parameter and percentage p. them of normal school such as Maximum likelihood method estimator and symbolizes her short (ML) and the method of moments and symbolized short (MO) and the least squares method and symbolizes her short(LS) and the least squares weighted and symbolized short (WL) and propose application Bayesian Method using (Lindley' s approximation) of this mixture distribution as not used in Iraq (by informed researcher) and study the behavior of a function failure rate for this distribution using expression w(t) which is also taught for the first time in Iraq, according to the informed researcher. Chapter III is divided into two sections. The first section includes the application of imitation style for generating data and performing a sample application based on the theoretical background. The second section reports about a field work on one of the public institutions for electrical industry. Chapter IV shows the results and conclusion of this study. It also suggests some recommendations for future research.

تقدير الدالة اللامعلمية للبيانات العنقودية == Nonparametric Regression Function Estimation of Clustered Data

Author name: حلا كاظم عبيد
Supervisor name: سجى محمد حسين الهاشمي
Specific topic: Statistics
Degree: Doctorate
Language: Arabic
University location: Baghdad
First pages:
Abstract: البيانات العنقودية تظهر في الكثير من العلوم الاجتماعية والصحية والسلوكية. وتتميز هذا النوع من البيانات بوجود الارتباط بين مشاهداتها. وممكن التعبير عن العنقدة من حيث العلاقة بين القياسات على الوحدات ضمن نفس المجموعة فان النماذج الاحصائية تحتم على حساب الار | Cluster data appears in a lot of social, health and behavioral sciences. And featuring this type of data link between the presences of her observations. And possible expression of clustering in terms of the relationship between measurements on units within the same group, the statistical models makes it imperative for the link account at every level, because failure to do so leads to misleading results. Hence the importance inside the Observations link to the estimating of the function non parametric for cluster data where the use of parametric method for ICON is always desirable to estimate some functions Because of the shape of the data is unknown in advance the appropriate function or as a result of the existence of some obstacles so it is the use non parametric method to estimate (smoothing) Nonparametric function.. Research has shown developed in recent times on the use of non parametric regression when parametric the assumptions are unfulfilled. And non parametric regression allows greater flexibility of functions dependent variables resulting from the data. Previous research has touched on the case of cluster data estimating the ways non parametric and semi parametric methods and was adopted state of neglect of the link within the same cluster property data that distinguish cluster data is particularly. And local kernel estimator achieved more efficient negligently correlation within clusters (even if the correlation is in the interest the study). While some touched on the case taking correlation between Observations per cluster using the estimated equations. Others had created the kernel methods in the case of cluster data behave completely different from the behavior of the capabilities of the spline estimator as has achieved kernel methods results more efficient when the neglect of the link within the clusters, while spline methods results achieved less variance of smoothing fixed parameters at taking the link inside clusters into account in the estimation process.So in this thesis will be nonparametric function estimating for clustered data using the Seemingly Unrelated Kernel Estimators, and The Generalized Least Squares Smoothing Spline Estimators and propose Robust methods and comparison of the methods listed above to indicate the best estimate of the nonparametric function estimating for clustered data, taking into account the structure of the link within the clusters were cluster data, The adoption of cluster data, which has the same number of explanatory variables within each cluster. To achieve this, thesis was divided into five chapters, the first chapter included introduction and aim of the research and reference review, either Chapter II now include the theoretical side which discussed the methods used to calculate the non parametric function of cluster data in the presence of the link. While included Chapter III experimental side (simulation) and the application addressed method in the second chapter and the statement of the best way has less (MAE) or (MSE). and either the fourth chapter includes the applied side to the real data for the proportion of white blood cells and its impact on the proportion of blood per patient (cluster) and Chapter V which includes the most important conclusions and the recommendations.it is through simulation experiments have been finding the best way to estimate the non parametric function for cluster data and a way The robust Generalized Least Squares Smoothing Spline Estimators in the case of a correlation. It was the application of all methods of the practical side using real data about the proportion of white blood cells and their impact on the proportion of blood hemoglobin for patients with blood cancer (leukemia).

استخدام اسلوب بيز التجريبي في تقدير معلمات انموذج الانحدار الخطي == Using Empirical Bayes Approach For Estimating Parameters In A Linear Regression Model

Author name: حازم منصور كوركيس عربو
Supervisor name: اموري هادي كاظم الحسناوي
Specific topic: Statistics
Degree: Doctorate
Language: Arabic
University location: Baghdad
First pages:
Abstract: The primary purpose of our thesis is to assess the importance of using empirical Bayes approach in regression analysis. At the first some empirical Bayes techniques in point estimation are considered. It is well known that in point estimation with a squared error loss function the Bayes estimator is the posterior mean. In the empirical Bayes approach we must construct a consistent sequence of estimators for this posterior mean using past experience. This construction is done for three general families of distributions. New estimators for the parameters in the simple orthogonal linear regression model are presented using not only the usual random sample of observations but also past experience in the form of previous estimators of parameters in similar but independent situations. The regression parameters are considered to be random variables. Bayes estimators are given for a squared error loss function. Even though the prior density of the parameter is unknown the Bayes estimator can be written in terms of the marginal density of sufficient statistic. This marginal density can be estimated empirically , thus forming the empirical Bayes estimator. Empirical Bayes estimators for the parameters in the general linear regression model are presented. These estimators by pass exact knowledge of the prior distribution of parameters by means of supplementary informations from similar independent experiments. The case in which the error variance is unknown and may vary from one experiment to the next is included. Some basic concepts in shrinkage estimators are introduced. The definition of multicolinearity as the existence of near linear relationships among the independent variables is given. Effects of multicolinearity on estimated regression coefficients are explained. Sources of multicolinearity and methods of detecting multicolinerity are presented. The method of ridge regression is given as one of several methods that have been proposed to remedy multicolinearity problems by modifying the method of least squares to allow biased estimators of the regression coefficients. The technique of ridge regression first proposed by Hoerl and Kennard has become a popular tool for data analysts faced with a high degree of multicolinearity in their data. Ridge solution properties and methods for choosing the ridge parameter are presented. The first method is graphical applied by using graphical display called 'ridge trace' the second method is the iterative method proposed by Hoerl and Kennard. The equivalence of ridge regression estimator with Bayers estimator is proved. Bayesian methods are employed for choosing the ridge parameter. An empirical Bayes estimator of the ridge parameter is presented. An empirical Bayes estimator of the ridge parameter which result in minimax ridge regression estimator under strawderman's loss function (formula 2.81) is also presented. By minimax estimator we mean an estimator which is uniformly better than the least square estimator in terms of risk. In the practical part of the thesis we apply ridge regression analysis to the set of actual data suffer from multicolinearity. Three methods are employed to determine the value of the ridge parameter. Comparisons between the three methods are made on the basis of various statistics that might go into the choice of the ridge parameter. According to these comparisons we conclude that the value of the ridge parameter obtained by using empirical Bayes approach (formula 2.78) is better than the other two methods. Ridge analysis is repeated for another set of experimental data obtained by constraint simulation. The same conclusion is obtained when the dependent variable is any one of the variables Y2 ,..... Y6.

مقارنة بعض المقدرات البيزية الحصينة مع مقدرات اخرى لانموذج GARCH(1.1) مع تطبيق عملي == A Comparing of Some Robust Bayesian Estimators With Another Estimators For Garch (1.1) With Practical Application

Author name: جنان عبد الله عنبر
Supervisor name: نزار مصطفى جواد الصراف
Specific topic: Statistics
Degree: Doctorate
Language: Arabic
University location: Baghdad
First pages:
Abstract: تعاني بعض السلاسل الزمنية من التقلبات او عدم الثبات في التباين مثل السلاسل المالية والاقتصادية والبيئية وغيرها, وقد يرافق ذلك وجود التلويث او القيم الشاذة في تلك السلاسل والذي يرافق عملية جمع البيانات في اغلب الاحيان ولاسباب عديدة قد يؤثر ذلك بشكل كبير عل | Some of time series suffer from volatility or instability in variation, such as financial , economic , environmental and other time seriesIt was accompanied by the presence of contamination or stray values in those chains that accompanies the data collection process often for many reasons, which greatly affect the estimation models parameters and thus makes the estimated models parameters and thus makes the estimated models are inaccurate and affect the future in the forecasting process this makes the process of estimation the traditional methods is not accurate and not feasible in practice and that is what led many researchers to find alternative methods of estimating for those methods reduce the impact of contamination and the volatility in the process of estimating the time series models,, including autoregressive conditional heteroscadestic models family (ARCH and GARCH). So the goal came thesis complement the work of researchers as thesis aims to find robust Bayesian estimators to the estimate first order generalized autoregressive conditional heteroscadestic model GARCH (1.1) when errors followed normal distribution, and that by proposing three robust Bayesian methods to estimate a method (y ?BM.Bayes) and method (BM.Bayes) and the reduced method (BM.Bayes Shrinkag). As was the use of certain methods of estimation models (GARCH), such as (MLE) traditional method of estimation and the method of (Bayes) and three robust bounded methods a (BM.Huber) and two methods by the proposed (BM.Hample) and (BM.Tukey). The use of simulation in the style of the experimental side for a comparison between the methods adopted in research using polluting ratios (0% 0.1% 0.10% 0.15% 0.20%) and volumes of samples (500, 1000.1500), In addition to the use of different values of the parameters it is found favorable proposed method (BM.Bayes) be when the values of the two parameters (?1, ?) close to each other when any correlation strength is high , Simulations were also on the values of the parameters of the real series that have been estimated in a manner program application (MLE) and some of them were far from any values that weak correlation strength , It turns out that the best method was the proposed (BM.Bayes.Shrinkag). In the practical side it has been stated in the application of the theoretical side of the building stages of the model and testing of those stages on a series of (1254) Show prices daily sales of Basrah, for the period (2 \ 1 \ 2008 - 31 \ 12 \ 2012) through the application of the proposed third method (the reduced method) (BM.Bayes Shrink) which was best when applied to the estimated values of the parameters in a manner (MLE) in the experimental side as it made less (MSE) and estimate the appropriate model GARCH (1,1) proposed the adoption of the reduced way (BM.Bayes.Shrinkag).

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).

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 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.

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).

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 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

تقدير نماذج الانحدار للبيانات الطولية مع الانقطاع في الاستجابة وتطبيقها في المجال الطبي == Estimate The Regression Model of Longitudinal Data With Drop - Outs In Response Variable With Application In Medical Field

Author name: نازك جعفر صادق
Supervisor name: ظافر حسين رشيد النجار
Specific topic: Statistics
Degree: Doctorate
Language: Arabic
University location: Baghdad
First pages:
Abstract: اكتسبت انموذجات البيانات الطولية في العقد الحالي اهتماما بالغا وتحديدا انموذج احتمال الانقطاع (انموذج الخليط النمطي) Pattern Mixture Model)(PMM)) الذي يعتبر من اهم الانموذجات التي توظف لاجل معالجة مشكلة فقدان المعلومات وخصوصا في البحوث الاقتصادية والطبية | Longitudinal data models have a great attention in the current decade specifically probability dropout model, Pattern Mixture Model (PMM) which is considered as the most important models that used in order to overcome the problem of dropout information es
1 2 3 4 5 6 7