“…Observing system design and optimization methods need to consider a hierarchy of approaches relevant for specific program drivers and priorities. Many studies have been conducted for rain-gauge network design using a variety of methods including statistical approaches, such as spatial correlation (Nazaripour & Daneshvar, 2017), multivariate and geostatistics (Dai & Ye, 2015;Putthividhya & Tanaka, 2012;Seo, Siddique, & Ahnert, 2014;Shaghaghian & Abedini, 2013), entropy (Chen, Wei, & Yeh, 2008;Karimi-Hosseini, Bozorg Haddad, & Mariño, 2011;Vivekanandan & Jagtap, 2012;Xu et al, 2015), and state-space stochastic models (Ndiritu, 2013). However, few of these studies considered socio-economic factors, such as population density, location, Table 2.…”