WASHINGTON, Oct 4 (Maggie Fox, Health and Science Editor/Reuters) - An unusual attempt to quantify the conflicts between Israelis and Palestinians shows that both act in retaliation for violent attacks, researchers reported on Monday.

They said their findings defy the perception that Palestinians attack randomly and demonstrate that both sides damage their own interests with acts of violence.

Writing in the Proceedings of the National Academy of Sciences, the researchers also said they hope to shed some light on the psychology that makes both Israelis and Palestinians feel they are the victims in the conflict.

We were a little frustrated by the amount of indoctrination and prejudice that are in the discussion around the Israeli-Palestinian conflict, Johannes Haushofer of the University of Zurich, who worked on the study, said in a telephone interview.

There is a lot of data out there lying around waiting to be understood, added Haushofer, who describes himself as both a neurobiologist and an economist.

Haushofer worked with Nancy Kanwisher of the Massachusetts Institute of Technology and Anat Biletzki of Quinnipiac University in Connecticut, who is a member of BT'selem, an Israeli human rights organization that collected Israeli military data used in the study.

The previous evidence suggested that Israeli attacks were often responses to Palestinian aggression, whereas this did not appear to be true for Palestinian attacks, Biletzki said in a statement.

This implied that the conflict was one-sided, with Palestinians attacking Israel, and the Israeli army merely responding to this aggression. Our findings suggest that the situation is more balanced than that.

ROCKET ATTACKS

They studied Qassam rocket attacks during 2000-2008, using a statistical method called vector autoregression to link the deaths of 4,874 Palestinians and 1,062 Israelis to various acts of violence, including air strikes, missiles and the destruction of homes.

The main finding is that both sides retaliate, Haushofer said.

They found that when Israeli forces kill five Palestinians, they increase the probability that Israelis will die from Palestinian attacks the following day by 50 percent.

Qassam rockets rarely kill anyone but they are easy for Palestinians to launch and are useful for studying attempts to wreak revenge, said Haushofer. There is a big media outcry every time they happen, he said.

Our findings suggest that the number of Qassams fired increases by 6 percent on the first day after a single killing of a Palestinian by Israel; the probability of any Qassams being fired increases by 11 percent; and the probability of any Israelis being killed by Palestinians increases by 10 percent, the researchers wrote.

Conversely, one day after the killing of a single Israeli by Palestinians, the number of Palestinians killed by Israel increases by 9 percent, and the probability of any Palestinians being killed increases by 20 percent.

U.S.-backed peace talks, launched a month ago in Washington, were plunged into crisis this week by the end of a 10-month Israeli moratorium on new settlement building in the West Bank.

Each side tends to see themselves as the victims, Haushofer said. By seeing themselves as victims they fail to see the violence that is actually caused by their own actions. (Editing by Todd Eastham)