Application of copulas in graphical models for inference of biological systems

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Tezin Türü: Yüksek Lisans

Tezin Yürütüldüğü Kurum: Orta Doğu Teknik Üniversitesi, Fen Edebiyat Fakültesi, İstatistik Bölümü, Türkiye

Tezin Onay Tarihi: 2016

Öğrenci: DAMLA DOKUZOĞLU

Danışman: VİLDA PURUTÇUOĞLU GAZİ

Açık Arşiv Koleksiyonu: AVESİS Açık Erişim Koleksiyonu

Özet:

Naturally, genes interact with each other by forming a complicated network and the relationship between groups of genes can be showed by different functions as gene networks. Recently, there has been a growing concern in uncovering these complex structures from gene expression data by modeling them mathematically. The Gaussian graphical model (GGM) is one of the very popular parametric approaches for modelling the underlying types of biochemical systems. In this study, we evaluate the performance of this probabilistic model via different criteria from the change in dimension of the systems to the change in the distribution of the data. Hereby, we generate high dimensional simulated data via copulas and apply them in GGM to compare sensitivity, specificity, F-measure and various other accuracy measures. We also assess its performance under real datasets. We consider that such comprehensive analyses can be helpful for assessing the limitation of this common model and for developing alternative approaches to overcome its disadvantages.