Startseite Wirtschaftswissenschaften Chapter 8 Selection of threshold in binary graphs of biological networks
Kapitel
Lizenziert
Nicht lizenziert Erfordert eine Authentifizierung

Chapter 8 Selection of threshold in binary graphs of biological networks

  • Vilda Purutçuoğlu und Başak Bahçivancı
Veröffentlichen auch Sie bei De Gruyter Brill
Smart Green Energy Production
Ein Kapitel aus dem Buch Smart Green Energy Production

Abstract

In recent years, accurately screening genes and their interactions has become increasingly important for personalized medicine. Understanding and detecting gene interactions are pivotal, but discovering these interactions is challenging due to the inherent structural and functional complexities of biological systems. These challenges include the high sparsity of gene interaction networks, the disparity between the number of genes and the number of samples, and the strong correlations among genes. The Gaussian graphical model (GGM) is a fundamental tool used to infer gene interaction networks. It represents relationships between biological entities through an undirected graph, where nodes denote genes and edges indicate conditional dependencies. To construct these graphs, the precision matrix, which contains conditional dependencies, is converted into a binary form, with 0 representing the absence of an edge and 1 indicating the presence of an edge. This conversion requires thresholding, a critical step that affects network construction and subsequent developments. Given the importance of network-based biological research for discovering novel biomarkers and drugs, threshold selection for the precision matrix has become a focal point. Various methods for selecting the optimal threshold are discussed in the literature, including both parametric and nonparametric approaches. For instance, Schneider et al. [4] propose a parametric threshold selection based on data distribution and a nonparametric method using Hill’s estimator for univariate extreme value analysis.

Abstract

In recent years, accurately screening genes and their interactions has become increasingly important for personalized medicine. Understanding and detecting gene interactions are pivotal, but discovering these interactions is challenging due to the inherent structural and functional complexities of biological systems. These challenges include the high sparsity of gene interaction networks, the disparity between the number of genes and the number of samples, and the strong correlations among genes. The Gaussian graphical model (GGM) is a fundamental tool used to infer gene interaction networks. It represents relationships between biological entities through an undirected graph, where nodes denote genes and edges indicate conditional dependencies. To construct these graphs, the precision matrix, which contains conditional dependencies, is converted into a binary form, with 0 representing the absence of an edge and 1 indicating the presence of an edge. This conversion requires thresholding, a critical step that affects network construction and subsequent developments. Given the importance of network-based biological research for discovering novel biomarkers and drugs, threshold selection for the precision matrix has become a focal point. Various methods for selecting the optimal threshold are discussed in the literature, including both parametric and nonparametric approaches. For instance, Schneider et al. [4] propose a parametric threshold selection based on data distribution and a nonparametric method using Hill’s estimator for univariate extreme value analysis.

Heruntergeladen am 12.12.2025 von https://www.degruyterbrill.com/document/doi/10.1515/9783110717655-008/html?lang=de
Button zum nach oben scrollen