2. Materials and methods
Surabaya is the capital city of East Java Province and recorded a
population of more than three million people in 2013. The city has
five regions (centre, north, east, south and west); encompassing 31
districts (kecamatan) and 160 villages (kelurahan) (Statistic Center
Board, 2012). This study was conducted in the eastern region of
Surabaya, East Java Province, Indonesia. Eastern Surabaya covers
an area of 91.18 km2
. The population was 746,532 in 2011 and the
population density was 72,297 people per square kilometre. Eastern Surabaya consists of seven districts, 42 villages, 390 community