Tag Archives: Bombings

Taking the Pulse of the Boston Marathon Bombings on Twitter

Social media networks are evolving a new nervous system for our planet. These real-time networks provide immediate feedback loops when media-rich societies experience a shock. My colleague Todd Mostak recently shared the tweet map below with me which depicts tweets referring to “marathon” (in red) shortly after the bombs went off during Boston’s marathon. The green dots represent all the other tweets posted at the time. Click on the map to enlarge. (It is always difficult to write about data visualizations of violent events because they don’t capture the human suffering, thus seemingly minimizing the tragic events).

Credit: Todd Mostak

Visualizing a social system at this scale gives a sense that we’re looking at a living, breathing organism, one that has just been wounded. This impression is even more stark in the dynamic visualization captured in the video below.

This an excerpt of Todd’s longer video, available here. Note that this data visualization uses less than 3% of all posted tweets because 97%+ of tweets are not geo-tagged. So we’re not even seeing the full nervous system in action. For more analysis of tweets during the marathon, see this blog post entitled “Boston Marathon Explosions: Analyzing First 1,000 Seconds on Twitter.”


Boston Marathon Explosions: Analyzing First 1,000 Seconds on Twitter

My colleagues Rumi Chunara and John Brownstein recently published a short co-authored study entitled “Twitter as a Sentinel in Emergency Situations: Lessons from the Boston Marathon Explosions.” At 2.49pm EDT on April 15, two improvised bombs exploded near the finish line of the 117th Boston Marathon. Ambulances left the scene approximately 9 minutes later just as public health authorities alerted regional emergency departments of the incident.

Meanwhile, on Twitter:


An analysis of tweets posted within a 35 mile radius of the finish line reveals that the word stems containing “explos*” and “explod*” appeared on Twitter just 3 minutes after the explosions. “While an increase in messages indicating an emergency from a particular location may not make it possible to fully ascertain the circumstances of an incident without computational or human review, analysis of such data could help public safety officers better understand the location or specifics of explosions or other emergencies.”

In terms of geographical coverage, many of the tweets posted during the first 10 minutes were from witnesses in the immediate vicinity of the finish line. “Because of their proximity to the event and content of their postings, these individuals might be witnesses to the bombings or be of close enough proximity to provide helpful information. These finely detailed geographic data can be used to localize and characterize events assisting emergency response in decision-making.”


Ambulances were already on site for the marathon. This is rarely the case for the majority of crises, however. In those more common situations, “crowdsourced information may uniquely provide extremely timely initial recognition of an event and specific clues as to what events may be unfolding.” Of course, user-generated content is not always accurate. Filtering and analyzing this content in real-time is the first step in the verification process, hence the importance of advanced computing. More on this here.

“Additionally, by comparing newly observed data against temporally adjusted keyword frequencies, it is possible to identify aberrant spikes in keyword use. The inclusion of geographical data allows these spikes to be geographically adjusted, as well. Prospective data collection could also harness larger and other streams of crowdsourced data, and use more comprehensive emergency-related keywords and language processing to increase the sensitivity of this data source.” Furthermore, “the analysis of multiple keywords could further improve these prior probabilities by reducing the impact of single false positive keywords derived from benign events.”


Analyzing Tweets Posted During Mumbai Terrorist Attacks

Over 1 million unique users posted more than 2.7 million tweets in just 3 days following the triple bomb blasts that struck Mumbai on July 13, 2011. Out of these, over 68,000 tweets were “original tweets” (in contrast to retweets) and related to the bombings. An analysis of these tweets yielded some interesting patterns. (Note that the Ushahidi Map of the bombings captured ~150 reports; more here).

One unique aspect of this study (PDF) is the methodology used to assess the quality of the Twitter dataset. The number of tweets per user was graphed in order to test for a power law distribution. The graph below shows the log distri-bution of the number of tweets per user. The straight lines suggests power law behavior. This finding is in line with previous research done on Twitter. So the authors conclude that the quality of the dataset is comparable to the quality of Twitter datasets used in other peer-reviewed studies.

I find this approach intriguing because Professor Michael Spagat, Dr. Ryan Woodard and I carried out related research on conflict data back in 2006. One fascinating research question that emerges from all this, and which could be applied to twitter datasets, is whether the slope of the power law says anything about the type of conflict/disaster being tweeted about, the expected number of casualties or even the propagation of rumors.  If you’re interested in pursuing this research question (and have worked with power laws before), please do get in touch. In the meantime, I challenge the authors’ suggestion that a power law distribution necessarily says anything about the quality or reliability of the underlying data. Using the casualty data from SyriaTracker (which is also used by USAID in their official crisis maps), my colleague Dr. Ryan Woodard showed that this dataset does not follow a power law distribution—even thought it is one of the most reliable on Syria.


Moving on to the content analysis of the Mumbai blast tweets:  “The number of URLs and @-mentions in tweets increase during the time of the crisis in com-parison to what researchers have exhibited for normal circumstances.” The table below lists the top 10 URLs shared on Twitter. Inter-estingly, the link to a Google Spreadsheet was amongst the most shared resource. Created by Twitter user Nitin Sagar, the spreadsheet was used to “coordinate relief operation among people. Within hours hundreds of people registered on the sheet via Twitter. People asked for or off ered help on that spreadsheet for many hours.”

The analysis also reveals that “the number of tweets or updates by authority users (those with large number of followers) are very less, i.e., majority of content generated on Twitter during the crisis comes from non authority users.”  In addition, tweets generated by authority users have a high level of retweets. The results also indicate that “the number of tweets generated by people with large follower base (who are generally like government owned accounts, cele-brities, media companies) were very few. Thus, the majority of content generated at the time of crisis was from unknown users. It was also observed that, though the number of posts were less by users with large number of followers, these posts registered high numbers of retweets.”

Rumors related to the blasts also spread through Twitter. For example, rumors began to circulate about a fourth bomb going off. “Some tweets even speci fied locations of 4th blast as Lemington street, Colaba and Charni. Around 500+ tweets and retweets were posted about this.” False rumors about hospital blood banks needing donations were also propagated via Twitter. “They were initiated by a user, @KapoorChetan and around 2,000 tweets and retweets were made regarding this by Twitter users.” The authors of the study believe that such false rumors and can be prevented if credible sources like the mainstream media companies and the government post updates on social media more frequently.

I did a bit of research on this and found that NDTV did use their twitter feed (which has over half-a-million followers) to counter these rumors. For example, “RT @ndtv: Mumbai police: Don’t believe rumours of more bombs. False rumours being spread deliberately.” Journalist Sonal Kalra also acted to counter rumors: “RT @sonalkalra: BBMs about bombs found in Delhi are FALSE. Pls pls don’t spread rumours. #mumbaiblasts.”

In conclusion, the study considers the “privacy threats during the Twitter activity after the blasts. People openly tweeted their phone numbers on social media websites like Twitter, since at such moment of crisis people wished to reach out to help others. But, long after the crisis was over, such posts still remained publicly available on the Internet.” In addition, “people also openly posted their blood group, home address, etc. on Twitter to off er help to victims of the blasts.” The Ushahidi Map also includes personal information. These data privacy and security issues continue to pose major challenges vis-a-vis the use of social media for crisis response.


See also: Did Terrorists Use Twitter to Increase Situational Awareness? [Link]

Did Terrorists Use Twitter to Increase Situational Awareness?

Those who are still skeptical about the value of Twitter for real-time situational awareness during a crisis ought to ask why terrorists likely think otherwise. In 2008, terrorists carried out multiple attacks on Mumbai in what many refer to as the worst terrorist incident in Indian history. This study, summarized below, explains how the terrorists in question could have used social media for coor-dination and decision-making purposes.

The study argues that “the situational information which was broadcast through live media and Twitter contributed to the terrorists’ decision making process and, as a result, it enhanced the effectiveness of hand-held weapons to accomplish their terrorist goal.” To be sure, the “sharing of real time situational information on the move can enable the ‘sophisticated usage of the most primitive weapons.’” In sum, “unregulated real time Twitter postings can contribute to increase the level of situation awareness for terrorist groups to make their attack decision.”

According to the study, “an analysis of satellite phone conversations between terrorist commandos in Mumbai and remote handlers in Pakistan shows that the remote handlers in Pakistan were monitoring the situation in Mumbai through live media, and delivered specific and situational attack commands through satellite phones to field terrorists in Mumbai.” These conversations provide “evidence that the Mumbai terrorist groups understood the value of up-to-date situation information during the terrorist operation. [...] They under-stood that the loss of information superiority can compromise their operational goal.”

Handler: See, the media is saying that you guys are now in room no. 360 or 361. How did they come to know the room you guys are in?…Is there a camera installed there? Switch off all the lights…If you spot a camera, fire on it…see, they should not know at any cost how many of you are in the hotel, what condition you are in, where you are, things like that… these will compromise your security and also our operation […]

Terrorist: I don’t know how it happened…I can’t see a camera anywhere.

A subsequent phone conversation reveals that “the terrorists group used the web search engine to increase their decision making quality by employing the search engine as a complement to live TV which does not provide detailed information of specific hostages. For instance, to make a decision if they need to kill a hostage who was residing in the Taj hotel, a field attacker reported the identity of a hostage to the remote controller, and a remote controller used a search engine to obtain the detailed information about him.”

Terrorist: He is saying his full name is K.R.Ramamoorthy.

Handler: K.R. Ramamoorthy. Who is he? … A designer … A professor … Yes, yes, I got it …[The caller was doing an internet search on the name, and a results showed up a picture of Ramamoorthy] … Okay, is he wearing glasses? [The caller wanted to match the image on his computer with the man before the terrorists.]

Terrorist: He is not wearing glasses. Hey, … where are your glasses?

Handler: … Is he bald from the front?

Terrorist: Yes, he is bald from the front …

The terrorist group had three specific political agendas: “(1) an anti-India agenda, (2) an anti-Israel and anti-Jewish agenda, and (3) an anti-US and anti-Nato agenda.” A content analysis of 900+ tweets posted during the attacks reveal whether said tweets may have provided situational awareness information in support of these three political goals. The results: 18% of tweets contained “situa-tional information which can be helpful for Mumbai terrorist groups to make an operational decision of achieving their Anti-India political agenda. Also, 11.34% and 4.6% of posts contained operationally sensitive information which may help terrorist groups to make an operational decision of achieving their political goals of Anti-Israel/Anti-Jewish and Anti-US/Anti-Nato respectively.”

In addition, the content analysis found that “Twitter site played a significant role in relaying situational information to the mainstream media, which was monitored by Mumbai terrorists. Therefore, we conclude that the Mumbai Twitter page in-directly contributed to enhancing the situational awareness level of Mumbai terrorists, although we cannot exclude the possibility of its direct contribution as well.”

In conclusion, the study stresses the importance analyzing a terrorist group’s political goals in order to develop an appropriate information control strategy. “Because terrorists’ political goals function as interpretative filters to process situational information, understanding of adversaries’ political goals may reduce costs for security operation teams to monitor and decide which tweets need to be controlled.”


See also: Analyzing Tweets Posted During Mumbai Terrorist Attacks [Link]

What do Travel Guides and Nazi Germany have to do with Crisis Mapping and Security?

I recently discovered Baedekers, a German-based publisher and pioneer in the business of worldwide travel guides. Founded in 1827 by Karl Baedeker, the travel guides became soon became so famous that baedekering actually became an “English-language term  for the process of travelling a country for the purpose of writing a travel guide or travelogue about it.”

Travel guides are of course very good sources of information and have multiple uses. Indeed, whilst interning as a Research Associate at the Congressional Research Service (CRS) in Washington DC some 10 years ago, I had access to the largest collection of travel guides I had ever seen in my life. Whilst crisis mapping the Haiti earthquake 2 years ago, one of the most important references we had  was the Lonely Planet Guide for Haiti. Indeed, we bought 2 copies just 48 hours after the earthquake. They must be the most used travel guides of Haiti that have never made it to Haiti.

No surprises then that the Nazi government commissioned the publication of several Baedeker guides of occupied regions of Europe such as Alsace and parts of Poland. But I was stunned to learn that the Luftwaffe reportedly used the Baedeker guides in their operations. Indeed, the “Baedeker Blitz” refers to a series of retaliatory raids by the German air force on several British cities in April 1942. While these cities, Exeter, Bath, Norwich and York, were of little strategic importance, they were picturesque and historically important. The raids were conducted in retaliation for the Royal Air Force’s widespread destruction of Lübeck, a historic German city.

The raids were called the “Baedeker Blitz” because it was “believed the towns had been “selected from the German Baedeker Tourist Guide to Britain, meeting the criterion of having been awarded three stars (for their historical significance).”  Indeed, Baron Gustav Braun von Stumm, a German propagandist is reported to have said: “We shall go out and bomb every building in Britain marked with three stars in the Baedeker Guide.” Some 1,600 British civilians were killed as a result and some 1,700 injured.

Clearly, travel guides provide situational awareness to both the intrepid traveler in Southern France and the German Luftwaffe in Great Britain. Banning and burning all travel guides as a result would be absurd. (Ironically, Baedeker’s offices were destroyed in a December 1943 air raid). Live crisis maps also provide situational awareness for multiple actors who may use these maps for various purposes. Should we therefore ban and delete all crisis maps? Probably not, even if we could. Instead, appropriate threat-mitigation strategies need to be developed and lessons learned have to be shared quickly and effectively. I do hope that the CrisisMappers Network‘s new Security Working Group will pave the way forward on this.