Data for this research is collected through questionnaires in Thai language from
February 19, 2013 to March 9, 2013. The 400 questionnaires are collected from
people who are age over 17 years old at the rest area aroundthe entrances of Central
Ladprao department store, Bangkok. The Central Ladprao department store is
selected, because it has a wide range of customers. This convenient sampling is the
basic random sampling method