يعد تحليل السلاسل الزمنية من المواضـيع الهامة في تفسير الظـواهر التي تحدث خلال فترة زمنية معينة. ان الهدف من هذا لتحليل هو الحصـول على وصف وبنـاء أنموذج مناسب من اجل اعطاء صورة مستقبلية واضحة للسلاسل الزمنية المدروسة وان السلاسل الزمنية اهم الادوات المستخدمة في بناء وتقدير والتنبؤ بالظواهر المختلفة وان الاستدامة المالية هي الحالة التي تكون فيها الدولة قادرة على الوفاء بالتزاماتها الحالية والمستقبلية من غير تغيير سياساتها اذ تعتبر من اهم المشاكل التي تواجه الصندوق لارتفاع اعداد الخارجين من الخدمة وارتفاع اعداد المتقاعدين مما يتسبب في ارتفاع حجم انفاق صندوق التقاعد والضمان الاجتماعي ولاعتماد الصندوق على ايرادات الاشتراكات التي يعتمد عليها بشكل شبه تام في تمويل الصندوق اذ استخدمت خصائص السلاسل الزمنية واختبار التكامل المشترك وانموذج متجه تصحيح الخطأ Vector Error Correction Model ومن ثم المقارنة من خلال المعايير,Sum Square Error Root Mean Square Error لإيجاد افضل انموذج من نماذج التمهيد الاسي للتنبؤ بالقيم المستقبلية، اذ تم التوصل الى ان السلاسل الزمنية (الانفاق والايراد) ساكنة بعد اخذ الفرق الاول وفق Augmented Dickey Fuller وتوصل البحث الى ان فترة الابطاء المثلى هي الفترة الثالثة بالاعتماد على معيار Akaike Information Criterion واشار اختبار Johansen – Juselius الى وجود علاقة توازنية طويلة الاجل بين المتغيرات وان هناك علاقة متجه من الايراد الى الانفاق وفق Vector Error Correction Model لان معلمة تصحيح حد الخطأ سالبة ومعنوية وان انموذج متجه تصحيح الخطأ بين نفقات وايرادات الصندوق خالي من مشكلة الارتباط المتسلسل وخالي من مشكلة عدم تجانس التباين وان افضل انموذج للتنبؤ للمتغيرات البحث هو التمهيد الاسي لمعلمتي هولت لأنه اعطى نتائج دقيقة وقريبة من القيم الحقيقية.
The aim of this paper is to derive a posteriori error estimates for semilinear parabolic interface problems. More specifically, optimal order a posteriori error analysis in the - norm for semidiscrete semilinear parabolic interface problems is derived by using elliptic reconstruction technique introduced by Makridakis and Nochetto in (2003). A key idea for this technique is the use of error estimators derived for elliptic interface problems to obtain parabolic estimators that are of optimal order in space and time.
This paper considers and proposes new estimators that depend on the sample and on prior information in the case that they either are equally or are not equally important in the model. The prior information is described as linear stochastic restrictions. We study the properties and the performances of these estimators compared to other common estimators using the mean squared error as a criterion for the goodness of fit. A numerical example and a simulation study are proposed to explain the performance of the estimators.
In linear regression, an outlier is an observation with large residual. In other words, it is an observation whose dependent-variable value is unusual given its values on the predictor variables. An outlier observation may indicate a data entry error or other problem.
An observation with an extreme value on a predictor variable is a point with high leverage. Leverage is a measure of how far an independent variable deviates from its mean. These leverage points can have an effect on the estimate of regression coefficients.
Robust estimation for regression parameters deals with cases that have very high leverage, and cases that are outliers. Robust estimation is essentially a
... Show MoreIn this study, we focused on the random coefficient estimation of the general regression and Swamy models of panel data. By using this type of data, the data give a better chance of obtaining a better method and better indicators. Entropy's methods have been used to estimate random coefficients for the general regression and Swamy of the panel data which were presented in two ways: the first represents the maximum dual Entropy and the second is general maximum Entropy in which a comparison between them have been done by using simulation to choose the optimal methods.
The results have been compared by using mean squares error and mean absolute percentage error to different cases in term of correlation valu
... Show MoreAbstract:
Under the state scenario, fiscal policy will not be able to use the oil surpluses optimally and economically and society, as long as these surpluses are not directed by public expenditure towards new productive investments and by following the path of fiscal policy after one year 2003 and until 2013 we note that it is based on the method of spending (excessive) consumption, and did not take any action towards the budget deficit planned at the beginning of the fiscal year, and the actual surplus at the end of the fiscal year, which represents the highest expenditure in the budget, Salaries and wages of workers in various government agencies with the expansion of spending on the security side.&n
... Show More- المقدمهIntroduction
الخيارات أحدى الأدوات المالية المشتقة التي تشتق قيمتها من قيمة الموجود الأساسي
Underlying Asset، وقد يكون الموجود الأساسي سهما عاديا أو مؤشر أسهم أو عقد مستقبلية سلع أو عقد مستقبلية على أوراق المديونية . وبالرغم من أن الدلائل تشير إلى أن التعامل بالخيارات يعود إلى أوائل القرن السادس العشر الميلادي آلا انه ونتيجة للعديد من الابتكارات ال
The objective of this study is to determination the content of some heavy metals (lead, cadmium, chromium) in colored tattoo stickers. twelve kinds of colored tattoo stikcers were collected from Baghdad markets, it was estimated heavy metals using atomic absorption spectrophotometer (Shimadzu A5000). The results indicated the concentrations of lead in all samples (1.61_1.00 mg / kg) and chromium in the three samples (0.85_0.97 mg / kg) while other samples are free of chromium , and cadmium. These elements are the components of printing inks and dyes in tattoo stickers, and this does not conform to the health and safety conditions for the packaging of food according to the organizations of the health and safety of
... Show More
The present article concerns one of the objects of media sociology under construction. The transformation of the rites in the use of the television contents in the era of digital technologies and media convergence. By an analytic contextual approach, based on the study of the uses, we formulate the following hypothesis: so many changes in the rites of uses are real, in particular at the young people, so, many pieces integer of the everyday life remain impervious to these changes, and it is true under the influence of a slowness of the social and cultural orders, rooted for a long time in the traditional social fabric. We shall then try to bring a sociological look to this societal, cultural, and communicational object that is the pas
The Arabian language was particularized in its style, which dazzles minds, so sophistication and diversity have been seen, which gives to words that aren't given to others in a specific weight and creator way, and applies to them even though semantics don't come only from the formula that came out
The Arabian language was particularized in its style, which dazzles minds, so sophistication and diversity have been seen, which gives to words that aren't given to others in a specific weight and creator way