Yemen Mosques, Suicide Bombings

Suicide bombers have attacked two mosques in the Yemeni capital during the rush for Friday prayers, killing 137 people and injuring 345 others, sources told Al Jazeera.

Three blasts were heard in two central mosques used by Houthi Shia Muslims, sources said.

A report on the Houthi-funded Al-Masirah TV channel said the bombers attacked the Badr and al-Hashoosh mosques during midday prayers on Friday. According to witnesses, one of the suicide bombers detonated his explosives inside the Badr mosque, causing panic as dozens of worshippers rushed toward the outside gates. A second bomber then attacked amid the panicked crowds trying to escape.

The Islamic State of Iraq and the Levant (ISIL) armed group, an offshoot of al-Qaeda, claimed responsibility for the attacks on Twitter. It threatened that these attacks were "only a part of the coming flood".

However, Al Jazeera's Rosiland Jordan said that intelligence experts believe ISIL's claim was questionable, saying they suspect either al-Qaeda in the Arabian Peninsula (AQAP) or anti-Houthi fighters were behind the attacks.

Specific Hypothesis and Results

The GCP event was set for 11:00 to 14:00 local time, intending to include the time of noonday prayers as well as some hours for the news to spread. The result is Chisquare 21490.193 on 21600 df, for p = 0.701 and Z = -0.526

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.