Terror Attacks in Copenhagen

Tens of thousands of Danes held torches and sang John Lennon’s Imagine at memorials across the country on Monday night to those killed by a suspected Islamist terrorist.

The prime minister, Helle Thorning-Schmidt, most Danish politicians and the leaders of other Scandinavian countries attended the remembrance ceremony in Copenhagen.

It was held near the cafe where a film-maker was killed in a burst of automatic weapons fire while attending a free speech debate on Saturday. Flags were at half-mast on all Danish public buildings on Monday.

"We have now experienced the fear that terrorism seeks to spread," the prime minister said, calling for national unity. “We know that there are fanatics who hold others’ right to live in contempt.”

The gunman, Omar el-Hussein, 22, a Dane of Palestinian descent, was killed by police hours after a second attack at 1am on Sunday on a synagogue where a girl’s Bat Mitzvah confirmation party was being held.

The first attack came at 3.30pm on Saturday afternoon during a free-speech debate in a cafe attended by, among others, the French ambassador and Lars Vilks, a Swedish artist who depicted the prophet Muhammad as a dog in a 2007 cartoon and whose life has been under threat ever since. Finn Nørgaard, 55, a film director attending the event, was reportedly shot dead at close range after going outside for an unknown reason at the time the attacker struck.

The gunman fled the scene, but at about 1am he struck again outside the city’s central synagogue, on a narrow street in the heart of Copenhagen, shooting dead Dan Uzan, 37, a Jewish security guard who was manning the door of a bat mitzvah party.

Specific Hypothesis and Results

The GCP hypothesis was set for 3:30 pm plus 10 hours local time Feb 14 2015, to include both the cafe attack and the synagogue murder which was at 1:00 am on Sunday. This is 14:30 Feb 14 to 00:30 Feb 15 UTC. The result is Chisquare 35798 on 36000 df, for p = 0.774 and Z = -0.752

Interpretation

The following graph is a visual display of the statistical result. It shows the second-by-second accumulation of small deviations of the data from what’s expected. Our prediction is that deviations will tend to be positive, and if this is so, the jagged line will tend to go upward. If the endpoint is positive, this is evidence for the general hypothesis and adds to the bottome line. If the endpoint is outside the smooth curve showing 0.05 probability, the deviation is nominally significant. If the trend of the cumulative deviation is downward, this is evidence against the hypothesis, and is subtracted from the bottom line. For more detail on how to interpret the results, see The Science and related pages, as well as the standard caveat below.

Standard caveat

It is important to keep in mind that we have only a tiny statistical effect, so that it is always hard to distinguish signal from noise. This means that every success might be largely driven by chance, and every null might include a real signal overwhelmed by noise. In the long run, a real effect can be identified only by patiently accumulating replications of similar analyses.