Ceren Unal

Dr. Ceren Unal

orcid

Research Focus & Metrics

Academic Career Length

9Years (2018-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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8 July 2019 in Communications in Statistics - Theory and Methods
Verified
Journal Article
Closed access
CUCeren Unal
Ceren Unal
CKCem Kadilar
Cem Kadilar
In this article, we propose families of estimators using the exponential function for the population mean in the case of non-response under two different cases. The expressions for the Bias and Mean Square Error (MSE) are derived to the first degree of approximation and theoretical comparisons are made with existing estimators in literature. Following theoretical comparisons, we demonstrate that the proposed family of estimators is more efficient than various compared estimators, under the obtained conditions. Furthermore, these theoretical results are supported numerically by an empirical study presenting the efficiencies of the proposed families of estimators.

20 November 2019 in Journal of Statistics and Management Systems
Verified
Journal Article
Closed access
CUCeren Unal
Ceren Unal
CKCem Kadilar
Cem Kadilar
In this article, we adapt the estimator based on the exponential function for the estimation of the population mean in the presence of non-response on both the study and the auxiliary variables. The expressions for the Bias and Mean Square Error (MSE) are derived to the first degree of approximation and theoretical comparisons are made with existing estimators in literature. We demonstrate that the adapted estimator is more efficient than compared estimators, such as classical ratio and regression estimators, Hansen-Hurwitz unbiased estimator, and the estimator of Singh et al. (2009) under the obtained conditions. Furthermore, these theoretical results are supported numerically by providing an empirical study on seven different data sets presenting the efficiency of the adapted estimator.

16 February 2023 in Earth Science Informatics
Verified
Journal Article
Closed access
PDF file
CUCeren Unal
Ceren Unal
GÖGamze Özel
Gamze Özel
TATuba Eroglu Azak
Tuba Eroglu Azak

1 June 2022 in Pakistan Journal of Statistics and Operation Research
Verified
Journal Article
Open access
PDF file
KRKHALID UL ISLAM RATHER
KHALID UL ISLAM RATHER
EKEda Gizem Koçyi̇ğİt
Eda Gizem Koçyi̇ğİt
CUCeren Unal
Ceren Unal
In this study, we adapted the families of estimators from Ünal and Kadilar (2021) using the exponential function for the population mean in case of non-response for simple random sampling for the estimation of the mean of the population with the RSS (ranked set sampling) method. The equations for the MSE and the bias of the adapted estimators are obtained for RSS and it in theory shows that the proposed estimator is additional efficient than the present RSS mean estimators in the literature. In addition, we support these theoretical results with real COVID-19 real data and conjointly the simulation studies with different distributions and parameters. As a result of the study, it was observed that the efficiency of the proposed estimator was better than the other estimators.

9 February 2022 in Journal of Taibah University for Science
Verified
Journal Article
Open access
CUCeren Unal
Ceren Unal
CKCem Kadilar
Cem Kadilar

31 December 2023 in Nicel Bilimler Dergisi
Verified
Journal Article
Closed access
CUCeren Unal
Ceren Unal
GÖGamze Özel
Gamze Özel
Hava kirliliği ile ilişkili riskleri daha iyi anlamak ve yönetmek için, hava kirliliği eğiliminin doğru bir şekilde tahmin edilmesi çok önemlidir. Ankara, Türkiye'nin İç Anadolu Bölgesi'nin merkezinde yer almaktadır. Hızlı nüfus artışı, düzensiz kentleşme ve artan sanayileşme nedeniyle, Ankara'da son yıllarda hava kirliliği ciddi boyutlara ulaşmıştır. Bu çalışma kapsamında, 2018-2021 yılları arasında Ankara iline ait bağıl nem, rüzgâr hızı, rüzgâr yönü, hava sıcaklığı, hava basıncı biçimindeki meteoroloji parametrelerinin, partiküler madde (PM10), kükürt dioksit (SO2), azot (NO), azot dioksit (NO2), azot oksit (NOX), karbon monoksit (CO) biçimindeki hava kirliliği göstergeleri üzerindeki etkilerinin incelenmesi amaçlanmıştır. Meteoroloji parametreleri ile hava kirlilik gösterge değerleri arasındaki ilişkilerin istatistiksel anlamlılığı regresyon analizinden yararlanılmıştır. Bu amaçla, PM10, SO2, NO, NOX, CO verilerine ayrı ayrı regresyon analizleri, meteoroloji parametreleri bağımsız değişkenler olarak alınarak uygulanmıştır. Elde edilen sonuçlar, PM10, SO2, NO, NOX, CO düzeyi ile meteorolojik parametreler olan rüzgâr yönü, rüzgâr hızı, bağıl nem, hava sıcaklığı, hava basıncı arasında negatif yönde ilişki olduğunu göstermiştir.