Six militants from the al-Qaeda in the Islamic Maghreb shot beach goers in a resort at Grand Bassam.
Security officials believe the attack was plotted by the Kurdistan Freedom Hawks (TAK), though there was no claim yet.
The study finds Nordic countries occupied the first five spots in the list.
Ong resigned on Friday after details of his extra marital affair with a fellow PAP member emerged in public.
Prime Minister Lee Hsien Loong says a by-election will be held in due course.
Iraq and Lebanon were the only Arab League members that disagreed with the decision, which was actively pushed by Saudi Arabia.
A 43-year-old police officer sustained deep gashes on his right arm and was hospitalized.
A Chinese foreign ministry spokesman hit out at Japan over the deal saying Tokyo was not a party to South China Sea dispute.
Tan had narrowly lost the last presidential election in 2011.
On Thursday, North Korea launched two short-range missiles that flew 500 km before splashing into the sea.
The hostages seen in the video are believed to be two Canadians, a Norwegian and a Filipino woman who were kidnapped in September.
The four regions most in need of humanitarian support are East Africa, Southern Africa, the Pacific Islands and Central America.
Mega metropolises London and New York were ranked at the sixth and seventh positions, respectively.
Suu Kyi's failure to reach a compromise with the junta on presidential candidate puts Myanmar on tenterhooks as election process starts.
Those who said they did not have any religious affiliation rose to 18.5 percent in the last year from 17 percent in 2010.