Mapping the social graph of weight loss groups

These are the graphs from some research on weight-loss groups on Facebook. I’ve processed the data so that:

  1. the size of dot is related to "total number of friends" – this only works where a user’s friends are publicly visible – quite often they aren’t, and I haven’t checked to see what the incidence of this privacy setting is generally and specifically
  2. all isolates (i.e. those users with no relationship to any other within the group) have been removed.
  3. personal weight loss support group

    This is the network graph of relationships on a personal weight loss support group. A college student set this up to support her own goals. She told me: " For my group, I just started it out by inviting all of my friends and then some people joined the group who found it in a search, I think. I am amazed by the amount of support I receive from random people who encourage me to keep on going. There are some spammers on the group who are just there trying to sell stuff and that gets annoying, but I know I can’t avoid them."

    unofficial weightwatchers support group

    This is the network graph of relationships on an unofficial weightwatchers group on Facebook. You can see that there are hardly any member-get-member relationships here. My friend Valery Yakubovich (who has a professorship in this sort of thing at Wharton) says:
    "It’s very common that organizations and interest groups become foci for personal networks. In fact, I believe that joint activities are the prevalent mechanism of tie formation."

    But it doesn’t look like it here. Looks to me that – while people may form relationships around special interests – they don’t mirror these on Facebook. Say I suffer from Meniere’s Disease (apparently true) and I participate in a Meniere’s support forum (not true at present), I don’t necessarily make those people my Facebook friends…

    blog-related support group

    Another example of the "not many personal relationships" graph for a weight loss support group on Facebook, this time, it’s the Facebook adjunct of a popular weight loss blog.

    How do people get information on weight loss? After a few interviews, I think the answer is like this:

    1. Influencers are "pull", rather than "push" resources (I’m thinking of going on a particular product, so I mention it casually to several friends to gauge consensus/temperature. One or more of them tell me "oh yes, I’ve heard of that", and one tells me "yes, My friend tried that, and lost 20lbs") This is not an active market. Most people won’t be evangelising, and evangelising behaviour may even appear suspicious.
    2. That said, people trust strangers to an extraordinary degree. Friend-of-friend endorsement is readily accepted, as is the anonymous commentary on boards & groups. Bloggers are slightly less trustworthy, it seems – because most of them have an axe to grind.