'Associate Professor of Public Policy Alberto Abadie examined data on terrorism and variables such as wealth, political freedom, geography, and ethnic fractionalization for nations that have been targets of terrorist attacks,' the Gazette said.

Abadie included both acts of international and domestic terrorism in his analysis, published in the Kennedy School's Faculty Research Working Paper Series.

Though after the 9/11 attacks most of the work in this area has focused on international terrorism, Abadie said terrorism originating within the country where the attacks occur actually makes up the bulk of terrorist acts each year.

Citing statistics from the MIPT Terrorism Knowledge Base for 2003, he said there were 1,536 reports of domestic terrorism worldwide, compared with just 240 incidents of international terrorism.

Before analyzing the data, Abadie believed it was a reasonable assumption that terrorism has its roots in poverty, especially since studies have linked civil war to economic factors.

However, once the data was corrected for the influence of other factors studied, Abadie said he found no significant relationship between a nation's wealth and the level of terrorism it experiences.

'Instead, Abadie detected a peculiar relationship between the levels of political freedom a nation affords and the severity of terrorism. Though terrorism declined among nations with high levels of political freedom, it was the intermediate nations that seemed most vulnerable,' said the Gazette.

'Like those with much political freedom, nations at the other extreme - with tightly controlled autocratic governments - also experienced low levels of terrorism.'

And "when you go from an autocratic regime and make the transition to democracy, you may expect a temporary increase in terrorism," Abadie said.

Abadie's study also found a strong connection in the data between terrorism and geographic factors, such as elevation or tropical weather.

"Failure to eradicate terrorism in some areas of the world has often been attributed to geographic barriers, like mountainous terrain in Afghanistan or tropical jungle in Colombia. This study provides empirical evidence of the link between terrorism and geography," Abadie said.

Abadie believes the connection between geography and terrorism is hardly surprising.

"Areas of difficult access offer safe haven to terrorist groups, facilitate training, and provide funding through other illegal activities like the production and trafficking of cocaine and opiates," Abadie wrote.