VAST 2008 Challenge

Mini Challenge 3:  Cell Phone Calls 

Authors and Affiliations:

I am thinking that pgage will fill this out?

Tool(s):

Three tools were used for this mini challenge.  The primary one was a visualization application written expressly for analyzing the cell phone data set; the application was written using the Processing programming language developed by Ben Fry and Casey Reas (http://processing.org)

Some analysis was done using Microsoft Excel and AWK scripts.

The ORA visualizer was used a few times to do a basic visual display of the data and to calculate changes in the values of standard social network metrics.  ORA was developed at the CASOS lab at Carnegie Mellon University. (http://casos.isri.cmu.edu/projects/ora/)

 

Two Page Summary:   YES or NO  (leave only your choice, the Two-Page summary is not mandatory)

 

        NO

 

 

ANSWERS:

Text Box:

Phone-1: What is the Catalano/Vidro social network, as reflected in the cell phone call data, at the end of the time period  

   PhoneNodes.txt

   PhoneLinks.txt

   Create your 2 files (using this format), save them as phonenodes.txt and phonelinsk.txt in the same directory as this form and link the above words to those files

 

Text Box:

Phone-2  Characterize the changes in the Catalano/Vidro social structure over the ten day period.

Detailed Answer:

Based on the assumption that 200 is Catalano, Estaban Catalano is likely 5 (the person 200 calls and is called by most frequently), and David Vidro is 1 (the individual whom 200 calls and is called by second-most frequently, and who is also one of the individuals with the highest numbers of calls made and received in the entire dataset).  Juan Vidro and Jorge Vidro, with whom Catalano would also keep in close contact, are probably 2 and 3 (who are called by 200 third- and fourth-most frequently).  Unfortunately, without further information we cannot decide which individual is which.

            If this is correct, then the Catalano/Vidro social network goes through a dramatic shift during on June 8, 2006 (though this was getting planned earlier).  At this point, the cell phone calls of all five individuals decline dramatically; while they all resume interaction, they engage in a minimum of conversations and none are within this original 1-2-3-5-200 group.  Rather, each member is now talking with people in a new block (as indicated in the phonelinks.txt) file.  While we could not find a specific reason for the fragmentation of the Paraiso leaders, we did successfully identify individuals who may be closely connected to it.

            The most important set of individuals who may be connected to the disruption are 300, 306, 309, and 397, whom we refer to as “the raft group”.  All four of these people only make and receive calls on days 8 – 10, talk to each other, and –besides 300, who is relatively inactive- both receive and make numerous calls. (Primarily receive - 306 receives calls from 40 people over three days, almost equaling David Vidro’s 51 over seven days.)  According to the geospatial data, on June 5 a raft containing four individuals and one dead person was picked up by the ship Manatee off the coast of Isla Del Sueno.  Taking travel time into account, we believe that it is possible that these four people were the riders on that raft, and that their return to the island possibly played into the hands of other individuals seeking control or otherwise disrupted the established power structure.

            There are several other individuals with interesting behavior around this period that may have had a role in the social network breakdown.  The first is the triad of 34, 165, and 203.  This group is centered around 165, who engages in routine dialogues with 203 and 34, and also calls 1 on an irregular basis; this is especially notable because he is the only person 1 calls on June 10, and the only other person to whom 165 speaks is 309, whom he calls four times.  If we are wrong in assuming that 200 is Catalano, it is possible that 165 is his actual number, 203 is Estaban, and that 1 is still Vidro (who suffers a falling out on day 7).  However, I find this unlikely.  Rather, I think that this triad has been expecting the actions of 309, and that 1 calls 165 in order to connect with 309 via 165.

            Secondly, I want to note 124, who is a gatekeeper figure.  124 routinely calls 2, more so than any other individual.  The only conversation 2 has on June 8 is when 124 calls, and 124 is also the last person whom 2 calls on June 10; that June 10 call is the only time 2 has ever initiated a conversation with 124.

The June 8 conversation follows a call to 124 by 397, a call 124 returns on June 9.  124’s only other contact is 9, who is similarly well connected –if less prominent- to 2.  Thus, it seems that 124 may be acting as bridge between the Paraiso leaders and the network belonging to 9, and is then used by the raft group to reach the now-fragmented leadership.

137 is the final figure of whom I want to take note.  He is part of an active though small network, but is primarily notable as the first person to contact Catalano after June 8 and the only person to whom 200 has spoken before June 8 who is not one of the main Paraiso leaders.  After several conversations, 200 then contacts 97 twice and 97 eventually initiates a call to 200 on June 10.  137 never speaks to any members of the raft group, and thus it is possible that he is a Paraiso loyalist, who provides Catalano advice as to how to proceed now that his network has imploded.  While the original leadership has fallen apart, the central Paraiso leader will begin to try and reclaim authority.