صفحه اعضا هیئت علمی - دانشکده علوم ریاضی و کامپیوتر

Professor
Update: 2025-03-03
Rahim Chinipardaz
دانشکده علوم ریاضی و کامپیوتر / گروه آمار
P.H.D dissertations
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تعمیم روش نمونه گیری بی درنگ درجوامع نامتناهی با واحدهای همبسته و پاسخ های تصادفیده و غیرتصادفیده
هادی فرخی نیا 1402 -
استنباط آماری در توزیعهای دایرهای وزنی
فاطمه شاه سنایی 1401 -
خانواده های جدیدی ازتوزیع های چوله نرمال متقارن دومدی
فروغ نقیبی 1400 -
یک تعمیم انعطاف پذیر در خانواده توزیع چوله-نرمال دوتکهای
نجمه شریفی پناه 1398 -
فرم پایایی در خانواده توزیع های وزنی
قربان پور-سامره 1396This thesis presents two basic studies about the weight distribution that concluded
the study on the invariant distribution and also the study of the amount of information
in the weighted observations. Two different concepts of invariance are considered.
With giving the class of the generating invariant weighted functions, the family of
invariant distributions has been studies. The results showed that the form-invariance
and family-invariance are two properties of the distributions in some families such as
the nonregular family, nonregular-exponential family and location-scale family. The
necessary and sufficient conditions for which the distributions in the expressed families
are form-invariant are given. The measure of information in weighted distributions and
double weighted distributions are obtained and compared with the information taken
from original ones. This was done for the exponential family and group families include
location family, scale family and location-scale family. The result is that the Fisher
information in double weighted distribution can be written as a function of Fisher
information in original and the weighted distribution. The conditions that the double
weighted distribution have more informative with respect to original distributions have
been given. Also this study demonstrated that the form-invariance is effective on the
amount of information in weighted distribution and also the form-invariant weighted
observations can be concluded stronger inference about population parameters than
the original observations. As an special family of distributions it was shown that
the exponential-weighted distribution can be expressed to a group families with more
information than the original distribution
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انعطاف پذیری در خانواده توزیعهای چوله-متقارن نرمال
راسخی كازرونی-مهدی 1394Statistical distributions are basis for modelling and parametric analysis in statistics. In these families of distributions, the symmetrical families are considered in the most branch of sciences. One of theses families, The normal distribution has great importance because of its properties. But some asymmetrical data (or data with skewness) are found in some sciences and phenomenon. For modelling this type data, skew symmetric distributions are emerged that popular procedures for creating this family are skew symmetric distribution with form Azzalini (1985), two piece skew symmetric distribution (Arellano Vale et al., 2005) and skew symmetric distribution with skewing mechanism.But these families can not model uni/bimodal data with wider range of kurtosis criterion. MA and Genton (2004) study a procedure for creating flexibility in family of skew symmetric with form Azzalini. In this thesis, modern procedures for creating flexibility in all families of skew symmetric normal distribution with some inferences on them are presented and introduced families are used to some real datasets.
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بررسی ویژگی های سری های زمانی آمیخته و استفاده از نمایش فضای حالت برای به هنگام سازی معادلات پیش بینی و برآورد پارامترهای مدل
محمدرضا یگانگی 1394The thesis presents two general frameworks of mixture time series models. The properties of proposed models are investigated in both time domain and state space. The sufficient conditions for ergodicity and stationarity of models are derived for mixture time series with autoregressive components. Further details are given for some special cases in time domain and state space among the parameter estimation procedures. The results show the good performance of $EM$ algorithm for small sample size and the approximative $EM$ algorithm for Large samples. Furthermore, filtering algorithm in state space has steady state providing the time domain represantation of model is ergodic. The update equations for parameter's estimates are given. The application of presented models in time series forecasting and discrimination is illustrated using three real time series data. The results show the good performance of mixture time series in forecasting and discrimination.
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برآورد تابع چگالی فرم درجه دوم نامعین در متغیرهای نرمال
قاسم ركابدار 1394In this thesis, the distribution of the quadratic form or its stochastic representation according to sum weighted of non-central chi-square variables is approximated. In case of the matrix of quadratic form has Wishart distribution, we illustrate stochastic representation of the quadratic form as weighted of non-central variables. The moments of the quadratic form are obtained in terms of its stochastic representation. Since, the moment generating function and moments of the quadratic form are known so the methods such maximum entropy and saddlepoint density estimation can apply to approximating the quadratic form distribution. Also, similar to the maximum entropy density estimation we propose a method by applying the recursive formula among moments of the multi-parameter exponential family with Stein's identity. As a usage, we obtained the stochastic representation of quadratic discriminant function in terms of sum weighted of non-central chi-square variables. We compared our method with those given in literature, via simulation study and in real data. The finding results reveal better estimation of tail probabilities, and less computation time with our method in most examples. In case of, the moments of distribution are unknown and we have random samples, then the proposed method can be handled for approximating distribution.
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آزمون فرض میانگین های مرتب شده در توزیع نرمال چند متغیره
ابوذر بازیاری 1390 -
ممیزی و خوشه بندی سری های زمانی در حوزه زمان
بهزاد منصوری 1389
Master Theses
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یك آزمون پرتوان تر برای مقایسه پارامترهای دوتوزیع نمایی
فاطمه عموری 1403 -
گسترش توزیع تابع توان منبسط شده جهت تخمین تابع بقا
عبدالله محمداحمید 1401 -
p-مقدار اصلاح شده برای فضای پارامتر محدود
عاطفه حمیدی 1401 -
آزمونهای موضعی پرتوانترین
ساهره ساعدی 1401 -
توزیع های خانواده نمایی وزنی
ناهید طرفی علی پور 1401 -
آزمون همگنی توزیع یکنواخت مقیاس با فرض مخالف دو طرفه و یک طرفه
غزاله احمدی 1400 -
آزمون های پرتوان تر اجتماع-اشتراک یا اشتراک-اجتماع برای مسئله آزمون علامت
حدیث مهرگان 1397 -
بررسی مقدار احتمال و احتمال پسین به عنوان برآوردگرفرض صفرآماری در توزیع نمایی
زهره فرهی 1395The comparision between P-value and posterior probability has a long history. The re-
sult so far have an reconcilability in one-sided hypotheses and irreconcilability in two-sided
hypotheses. From the decision-theory point of viwe, there are a few articles about the compar-
ision between these two criterion. In this thesis, we considered the admissibility of these two
criterion for two important distributions Exponential distribution and Parato distributiob. It
was shown that in both distributions Exponential and Parato for one-sided hypotheses there
is the same results for P-value and posterior probability. both are admissible estimators for
null hypotheses. Also for two-sided hypotheses, it has been shown that there is a irreconcil-
ability between these to criterion, in Exponential distribution while posterior probability is an
admissible estimator for null hypotheses, P-value is a inadmissible estimator. In the case of
restricted parameter space, the P-value is not a admissible estimator in one-sided or two-sided
hypotheses. A modified P-value was given to lead a admissible estimator.
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یک آزمون پرتوان تر برای مقایسه بین میانگین های دو جامعه ی مستقل پواسن
الهام فرهادی 1395In classical infrence, the most optimum property is uniformly most powerful (UMP) test. However, In many cases these tests are not available. Also, these tests are not available in two-sided hypothesis for the exponential family.Therfore, the ststisticans suggested more powerful tests which are weaker optimal tests with respect to UMP tests for two-side hypothesise, In exponential familya for one or two-sidehypothesis with a nusiance parameter the optimal tests leads to conditional tests which are UMP in the unbiased tests. In such situations, we search for more powerful tests than the classicl UMP unbiased tests. In this study a more powerful test then UMP unbiased test has been suggest.In this Thesis(research) We considered both one-sided and two-sided hypotheses for comparing two poisson means and also with considered one-sided hypotheses two binomial proportions. The performance of this method has been investigated by numerical stuy.
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مقایسه سری های زمانی با طول نابرابر در حوزه فرکانس
عزیزیان-علی 1394Discriminate and classification are two main problems in statistical multivariate analysis. Clustering of time series using Fourier analyses is one of these method and is important because of independent periodogram calculations at different frequencies. This leads to have more easy calculation in cluster analysis or comparison between two time series.
The problem often arises in practice is unequal length of the time series.
In this study an approach has been given that using the increasing or decreasing the length of time series we catch the same length of two series.
In thesis several important distances clustering time series, including Kullback-Leibler, Chernoff and Mahalanobis, are studied with unequal observations in each series.
We also studied the performance these distances with simulation. We have shown that the Chernoff distance is more efficient than any other distance.
Finally using the Chernoff discrimination distance, we clustered the populations in 19 states of America.
The results showed that these 20 states can be classified in two cluster southern (large population) and north-east stats (small population).
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رویکرد بسامدی و بیزی برای آزمونِ واریانسِ توزیع نرمال
بهزاد فلاحی فرد 1394This thesis is concerned with the comparison of P-value and Bayesian measure in two-sided and one-sided hypothesis for the variance of Normal distribution with known and unknown mean (nuisance parameter). For tow-sided hypotheses, First, using fixed prior distributions for test parameter, the posterior probability is obtained and compared with the P-value when an appropriate prior is suggested for the nuisance parameter. Second, lower bounds of the posterior probability of H0, under a reasonable class of prior distributions are compared with the P-value.Results revealed showed that without nuisance and in the presence of nuisance parameter for the model, these two approaches can lead to different results in statistical inference. Then, sensitivity of posterior probability of null hypothesis is investigated by different prior distributions. The results also showed that sensitivity was poor and different prior distributions for nuisance parameter were not affected by the comparison between two methods. But, in contrast to two-sides hypotheses, when we use a fixed prior, there is reconcilability between two approaches in one-sided hypotheses
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مقایسه بیزی و فراوانی گرا در آزمون فرض مربوط به میانگین توزیع نرمال چند متغیره
سعید حبیب الهی تبار 1394The problem of comparing the significance measures and the Bayesian measures in the one-sided and two-sided testing problems has been widely considered by statisticians. The most of founds indicate that there is different results between Bayesian and classical point of views in two-sided testes. However, there is no the case for one-sided tests in which the results are similar. Most of the previous works are focused in one dimension cases and without nuisance parameters. In this thesis, the comparision between Bayesian measures are considered in multivariate normal distribution. Due to prior distribution selection in Bayes test, the comparison is achieved in two methods. In the first method, a specific prior distribution is chosen and posterior probability of null hypothesis computed. This posterior probability of null hypothesis is then compared with the P-value. In the second method, the lower bound of the posterior probability of null hypothesis, over some reasonable classes of prior distribution are derived and compared with the P-value. Also, it shown that the sensivity with respect to prior distribution is weak when we used the posterior probability affected to comparison between two methods. It is shown that, the conflict between P-value and Bayesian evidence in addition to the prior distribution of other factors is highly dependent on the sample size and existance nuisance parameters in sample. So that unlike the univariate agreement between the two styles is the the test in multidimensional differences between the two measures exist. The two-sided test when nuisance parameter in the model is present as in univariate, there is difference between the two test methods.
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شناسایی تکه های پرت جمع پذیر در سری های زمانی اتورگرسیو
بندانی سوسن - الهام 1394In time series analysis, it may be exist a sequential outlier points at an interval. This set of outliers called patch of outlier, recently has been paid attention by the statisticians. Detection of additive outlier patches may be difficult in the presence of severe masking and swamping effects. Recently, Bayesian approaches have been used in time series, to detect of outlier patch with Markov Chain Monte Carlo algo- rithm. Justel et al. (2001) propose a procedure to detect patches of additive outlier in an autoregressive process. Adaptive Gibbs sampling identifies the beginning and the end of possible outlier patches using the existing Gibbs sampling, then carries out an adaptive procedure with block interpolation to handle patches of outlier. We use adaptive Gibbs sampling to detection additive outlier patches and estimate their outlier magnitude in AR models. The simulation study shows that this procedure has relatively high effectiveness. As an application example the data of monthly golden Bahar Azadi coin prices are considered. This data collected from April 1985 to October 2014. The data anal- ysed to detect additive outliers patches and estimate their outlier magnitude. The results show that this series has not additive outliers patches but it has some additive outliers.
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آنالیز ممیزی فرایند های چند متغیره مانای موضعی
لیلا صالحی 1392 -
شناسایی تغییرات فصلی در سری های زمانی با استفاده از فضای حالت
رضا ذبیحی مقدم 1392 -
تشخیص داده های پرت جمع پذیر در سری های زمانی فصلی تلفیقی
نادیا كوراوندبردپاره 1391 -
ممیزی سری های زمانی به روش هسته
راضیه دهقانیان 1391 -
بررسی توافق معیارهای بیزی و کلاسیک در آزمون های یک طرفه توزیع نمایی با حضور پارامتر مزاحم
خدیجه مهری 1391 -
توابع ممیزی خطی برای سری های زمانی ایستا و مقایسه آن با توابع ممیزی درجه دوم
لطیف سعیدی 1390 -
براورد پارامترهای سری های زمانی دینامیکی با استفاده از فضای حالت
منا دومانی 1390 -
رگرسیون خطی موضعی با دادههای سری زمانی
رضا رستا 1390 -
پیش بینی در فضای حالت به کمک هموارسازی نمایی
زهره السادات حسینی 1389 -
بررسی نقاط پرت در مدل های GARCH
هدی كامرانفر 1389 -
بررسی نقاط پرت دادههای در سری های زمانی چند متغیره
الهام مختاری 1389 -
نمونهگیری وزنی و تاثیر تابع وزن در برآوردهای نقطهای و آزمونهای فرض در بعضی از توزیعهای خانواده نهایی
سیدمحمدرضا علوی 1387 -
ممیزی ناپارامتری دادههای سری زمانی
سیده حبیبه میرعبدالعظیمی 1387 -
بررسی سریهای زمانی طبقهبندی شده و استفاده از روش پوشش طیفی در تحلیل آنها
حسین صیدخانی 1385 -
مقایسه آزمون معنیداری و بیز در توزیع نمایی
ابوالحسن قاسمی 1385 -
ممیزی لجستیک چند لایه با استفاده از شبکههای عصبی
فردوس محمدی بساتینی 1385 -
آزمون علیت بین دوبردار در مدلهای ARMA چند متغیره
مهدی پژمان 1384 -
انتخاب پارامتر هموارکننده در رگرسیون خطی امکانی
رباب افشاری 1383 -
آنالیز ممیزی طیفی در حوزه فرکانس سریهای زمانی براساس معیارهای جداسازی کولبک- لیبر و چرنوف
سارا شفیعیبابایی 1383 -
بررسی نقاط پرت در دادههای سریهای زمانی
پریسا ذوالفقاری 1382 -
تحلیل ممیزی آمیخته گوسی
قاسم ركابدار 1382 -
مقایسه آزمون معنی داری و بیز در توزیع نرمال ونرمال چند متغیره
اسیه ابطحی 1381 -
سری های زمانی چندمتغیره وکاربرد آن درپیش بینی حسابهای مالی ایران
فرشید خانزاده 1380 -
برآورد و پیش بینی در فضای حالت با استفاده از صافی کالمن
رضا منیعی 1378 -
آنالیزممیزی و استفاده از آن در تقسیم بندی کشورها
مهدی یعقوبی اول ریابی 1370