Archive for March, 2009

Conference on 2-mode data

March 30, 2009

Is this cool or what? An entire conference devoted exclusively to 2-mode networks. Organized by some really sharp people. And a great excuse to visit Amsterdam. For more info, here’s the conference url:

The conference includes several workshops.

Quick overview of network analysis for a reporter

March 4, 2009

Hi, I understand you are looking for a high-level description of UCINET and what it is used for.

Given network data (such as who is kin of whom, who is boss of whom, who talks to whom, how gives money to whom, etc) the program computes a bunch of metrics that illuminate the structural role played by individual nodes in the network (or specific relationships, or entire groups).

So, for example, it can model the expected amount of information that is flowing through the network that will reach a certain node, and model when it will receive it. Typical guiding theoretical principle is that nodes that are more central in the network (in various different senses), have certain advantage over other nodes, which enables us to predict that they will perform better than others, or get more rewards, or will increase in status/power. Etc. At the same time, we can estimate which nodes will do the most damage on removal from a network, in terms of damaging that network’s abilities to transmit information and orders.

Academic Research. At the most general level, UCINET is used to investigate two kinds of questions: (a) variation in performance/success, and (b) homogeneity in attitudes, beliefs and behaviors.

Research into the first question can be broadly termed social capital research – it is about the benefits of social ties and social positions and ultimately network structure. It answers the question, what does it get you to be located where you are in a network that has a certain structure. So classical work on how people get ahead, how do you get jobs, who’s got the power, why are some more creative than others, etc are all part of this research stream/.

Research into the second question can be broadly termed diffusion or peer influence research. It is about how one’s beliefs, attitudes, practices, and so on are shaped by the people (or other entities) we interact with. Classical work on language acquisition, becoming a criminal, fashion and consumer marketing, politics, and so on part of this research stream.

Applied Research. All of the academic work has obvious implications for many applied fields – for example, the diffusion research is key to shaping how pharmaceutical companies identify physician “key opinion leaders” and try to influence the influencers. But I would say that there are three well-developed applied SNA areas: criminology/terrorism, public health, management consulting.

Criminology/terrorism. A key goal here is breaking up criminal networks – “whack-a-mole” type applications where you try to figure out which are the key players such that removing them from the network (i.e., arresting, shooting, discrediting) would do the most damage to the network’s ability to cause problems for others. In this area, much of the work is directed toward figuring out how to obtain the network data in the first place, since the terrorists won’t fill out surveys. Essentially, the problem they have is way too little good data (e.g., who trusts whom, reliably measures) and way too much bad data (terabytes of data linking people to others in highly circumstantial and unreliable ways).

Management Consulting. The goals here are usually the opposite the criminology goals. Here you want to strengthen the network and help it accomplish its goals more efficiently. The network analysis done by UCINET can be used in a number of ways. For example, in the case of post-merger integration (PMI), you have two companies merging not only their technologies, but their cultures and their people (and with them, their networks). A network analysis quickly tells you where the networks are integrating and where they are still remaining apart. You can also use UCINET to discover key nodes who (a) should be given a strong stake in the company because they would leave a large hole if they left, and (b) have the “network signatures” of future stars, and should be groomed  for promotion, and (c) maybe bottlenecks because they are so good that too much is getting channeled their way, and the system is become slow and brittle (when he has cold, everything grinds to a halt).

Health. The goals here a combination of the criminology and management consulting goals. On the epidemiological side, you have a contagious disease that is spreading from person to person. By doing a network analysis, you can figure out which individuals (or collectivities) need to be immunized/quarantined in order to slow the spread of the disease as much as possible. This is the same problem as the stopping of a terrorist network problem. On the other side, there is the patient care side, in which patients get the care they need by having helpful and knowledgeable friends that are either doctors themselves, or are good at asking questions of doctors, or who can provide good referrals, etc. Also patients who are able to connect their various specialists so that they talk to each to each other can achieve much better outcomes for themselves.