İstatistik Bilim Dalı yayınlarını içerir. http://hdl.handle.net/20.500.12416/4381 2026-10-28T16:30:11Z 2026-10-28T16:30:11Z Türker Bayrak, Özlem Köksal, Gülser Okandan, Ender http://hdl.handle.net/20.500.12416/7598 2024-03-18T11:47:25Z 2005-01-01T00:00:00Z

Forecasting The Natural Gas Demand At New Locations A Case Study For Turkey Türker Bayrak, Özlem; Köksal, Gülser; Okandan, Ender

2005-01-01T00:00:00Z Dener Akkaya, Ayşen Türker Bayrak, Özlem http://hdl.handle.net/20.500.12416/7151 2024-02-09T11:41:20Z 2017-01-01T00:00:00Z

A New Estimation Technique for AR(1) Model with Long-Tailed Symmetric Innovations Dener Akkaya, Ayşen; Türker Bayrak, Özlem In recent years, it is seen in many time series applications that innovations are non-normal. In this situation, it is known that the least squares (LS) estimators are neither efficient nor robust and maximum likelihood (ML) estimators can only be obtained numerically which might be problematic. The estimation problem is considered newly through different distributions by the use of modified maximum likelihood (MML) estimation technique which assumes the shape parameter to be known. This becomes a drawback in machine data processing where the underlying distribution cannot be determined but assumed to be a member of a broad class of distributions. Therefore, in this study, the shape parameter is assumed to be unknown and the MML technique is combined with Huber’s estimation procedure to estimate the model parameters of autoregressive (AR) models of order 1, named as adaptive modified maximum likelihood (AMML) estimation. After the derivation of the AMML estimators, their efficiency and robustness properties are discussed through simulation study and compared with both MML and LS estimators. Besides, two test statistics for significance of the model are suggested. Both criterion and efficiency robustness properties of the test statistics are discussed, and comparisons with the corresponding MML and LS test statistics are given. Finally, the estimation procedure is generalized to AR(q) models.

2017-01-01T00:00:00Z Akyürek, Turgut http://hdl.handle.net/20.500.12416/7057 2024-02-01T12:49:44Z 2017-01-01T00:00:00Z

Assessment of the Use of AutoCAD in Mechanical Engineering Technical Drawing Education Akyürek, Turgut : AutoCAD is one of the widely used software tools in engineering education. In this study, a general assessment of AutoCAD for the usage in the mechanical engineering technical drawing education is made. AutoCAD is assessed in terms of the fulfilment of the requirements defined for the main two technical drawing courses. AutoCAD is assessed in terms of its capability in meeting the requirements of the technical drawing courses

2017-01-01T00:00:00Z Türker Bayrak, Özlem Aytaçoğlu, Burcu Yüksel Haliloğlu, Ebru http://hdl.handle.net/20.500.12416/7054 2024-02-01T12:49:10Z 2015-01-01T00:00:00Z

Global Krizler için Doğrusal Profillere Dayalı Kontrol Şemaları ile Oluşturulan Erken Uyarı Sistemi Türker Bayrak, Özlem; Aytaçoğlu, Burcu; Yüksel Haliloğlu, Ebru

2015-01-01T00:00:00Z