Abstract
RealContacts is a web and email based service based on the evolving science of "Small World Networks." The service helps you communicate with your extended personal and business network of contacts and accomplish things while preserving privacy. The first application helps you find staff or jobs, and other applications are in development. This paper summarizes the background science and outlines the new way that RealContacts uses the Internet to improve the efficiency of communications within extended social networks.

Introduction
RealContacts is an unusual blend of business and science. Our team has primarily a business background, and our main focus has been to create a service that people will find useful and valuable. However, the product's overall architecture and design has been heavily influenced by the emerging science of "Small World Networks." The aim of this paper is to give a brief outline of the science behind RealContacts. The key scientific ideas are outlined in a very cursory way - just enough to set the scene as to what we are attempting to do with RealContacts. There are a number of references at the end of the paper that do a much better job of explaining the science in detail.

Background Science

Six Degrees of Separation
In the mid 1960s sociologist Stanley Milgram from Harvard University carried out a series of famous experiments tracking how letters with no address sent to random parts of the US made their way though networks of people back to the sender. The average number of steps required to get back to the recipient was less than 6, and interestingly the majority went via 2 highly connected contacts of the recipient. From this Milgram developed what he called the "Small World Hypothesis," which said, in effect, that everyone was connected to everyone else by six degrees or less. Later, the famous Six Degrees of Kevin Bacon online game site made the idea popular, by linking all Hollywood actors to Kevin Bacon based on films they had made together.

Strength of Weak Ties
In 1973 Mark Granovetter published a classic paper called "The Strength of Weak Ties," that analyzed how people found jobs. He found that most people - about 56 percent - found their job through a personal contact.

The most surprising results were:

• Only 16% of people found jobs through a contact they saw "often" (close friend or family)
• 84% got their job through a contact they saw "occasionally" or "rarely"

A key reason for these results is that the people you know well are likely to also know each other and therefore know about the same opportunities. It is the people who you interact with infrequently who are likely to know about different opportunities, and hence be the most valuable contacts for finding a job. This research highlighted that the weak ties between people are very important in linking people within larger social networks.

Small World Theory
In 1996 Cornell University Graduate student Duncan Watts was working on the question of how fireflies and other animals synchronize bursts of light or sound. He began studying computer models of networks with his doctoral supervisor, Steve Strogatz. They found out that adding just a few random links to an otherwise clustered network dramatically lowers the degree of separation between nodes. This relatively small change in the way a network is connected makes a dramatic improvement in the efficiency of information transfer.

This subtle, simple mathematical network pattern has been found to exist in such diverse networks as:

• Power grids
  
• Food webs for ecosystems
  
• The way words are linked in sentences
• The structure of the Internet
  
• Neurons in the brain
  
• The nervous system of worms

Science author Mark Buchanan noted, "These networks turned out to have almost exactly the same small-world structure as the social worlds. For some mysterious reason, Watts and Stragatz's odd-looking graphs seemed to be pointing towards some deep organizing principle of our world." This elegant finding by Watts and Strogatz, summarized in a 1998 paper in Nature titled, "Collective Dynamics of 'Small World' Networks," has stimulated a vast amount of subsequent research.

Small Worlds Theory, the Internet, and RealContacts
The Small Worlds Theory applies at three main levels on the Internet:

1. The mechanics of information flows through hardware networks of computers and routers. Bill Cheswick of Bell Laboratories and Hal Birch of Carnegie Mellon University pioneered the mapping of these physical connections and have produced some spectacular images of the Internet.
2. The network of information links (URLs) among web pages via the World Wide Web. This is quite different from the network pattern of physical flows of information. Albert-László Barabási and his colleagues at Notre Dame University built a computer "robot" to wander the web and map these connections. This research led to the identification of other generic rules about the mathematics of small worlds that emphasized the importance of hubs and how they influence the robustness of networks.
3. The flow of information between individuals, primarily through email and web pages. Again this is different from the physical flows of information or the way web pages are linked to each other. It is about the way information travels in social networks using the Internet as a tool. This is the main area of interest for RealContacts. Our aim is to set up a tool that uses the Internet to allow easier communication within social networks.

At the moment there is an information glut in the world. The current environment is creating so much information noise that we can barely cope. We are constantly bombarded with ideas, information, and advertising from various media, and the global reach of the Internet is accelerating this. As the volume goes up we need even more advanced filters, and one of the key ways people filter information is to get it from people they know.

We value information from people we know more than that from people we don't know, but the way that valued information is transferred at the moment is ad-hoc and time consuming. The aim of RealContacts is to build a tool that allows information flows between groups of trusted people to be easier for everyone involved.

RealContacts operates as a type of router or filter for information in your extended social network. It shields you from the unreliable information and lets in pre-qualified, quality information. More importantly it allows you to find out about things that are not available to the general public. It does this not by requiring complex "rules" to filter information coming from the general public, but by simply admitting only the information coming from people you know, and the people they know, and so on out to a controllable number of degrees. Because users have total control over who they choose to be connected to, the personal networks are self regulating.

Rules that have guided the design of RealContacts
Starting with the background theory we came up with a few basic design rules for RealContacts:

• You (the user) must have total control over the information flows and you get to change this by deciding who you are connected to, what type of information you are interested in, and how deep in the network you want to disseminate and view or be notified of information
• You cannot get different information than you might otherwise get from normal social interaction. The process is simply more efficient and less hassle for everyone involved
• Your privacy is totally protected. For example, no other user can see who your personal contacts are, yet information can still flow in the social network.
  Lots of different types of information can flow within the social network without the need to rebuild your social network each time.
• It has to be as much like your normal social interactions as possible

We chose to implement RealContacts using standard web application and database components. One open standard protocol initiative for definition of social network information and exchange of that information is underway, called FOAF (Friend of a Friend). However, we have not yet pursued the use of FOAF primarily because of our focus on the privacy of our users. We are firmly of the opinion that while people are keen to share information via their network of contacts, most people do not want to share details of who their contacts are. We believe that any system that does share personal contact information will only appeal to a small subset of people, who are willing to sacrifice their privacy and that of their contacts in order to meet more contacts. However, an open and secure protocol for user controlled exchange of social network information is an attractive objective, but only if all the users involved (not only the initiator) are protected and are assumed to "opt-out" of information exchange by default. This is a complex issue, and we prefer to focus for the time being on a complete application platform with strong privacy protection.

Practical Applications of a RealContacts Network
Although these are interesting ideas we know that people will not use a web service unless they have a compelling reason in their personal or business life. SixDegrees.com, the most well known early web site to illustrate the Six Degrees of Separation for individual users, highlighted that relying on the curiosity appeal of the phenomenon without compelling and easy to use applications is not sufficient for success. We have designed RealContacts so that people have a strong specific reason to use the service and full control over who is able to see their information and interact with them.

If these ideas are as important as we think then they should help solve real everyday issues for people. Of the scores of potential ideas to start off with we identified finding a partner and finding a job as two things that are important and at the same time reliant on personal networks.

FriendlyConnections.net
Note: this service is not currently available online to the general public. Our first application was in 2001, when we built the web site friendlyconnections.net to allow people to meet people and find dates through their extended network of contacts. One of the key reasons we started with dating was that most people in long-term relationships seem to have met through mutual friends. While the mechanics of this service worked well and there were some successes the main obstacle was people's resistance to being involved with Internet dating.

RealContacts Jobs Application
Finding jobs or staff is a much more appealing application for the following reasons:

• There is none of the social stigma attached with dating. The fear of being seen to be job-hunting is overcome through tight protection of privacy and identity.
• People know that finding a great job or staff often happens through networks of contacts and both employers and jobseekers are strongly motivated
• Companies currently pay significant sums of money to recruiters and our service is a fraction of the price, so we have a strong business model
• People are happy to be involved in a job network because they intuitively understand that even if they are not looking for work or staff now that by building a network it can be of use in the future
• Social networks reach across countries and even across borders, allowing employers to reach out to jobseekers they could never afford to reach through traditional media campaigns.

The current application, while still being improved, is already successfully helping employers find staff and jobseekers find jobs. Click here to see some feedback from customers.

A lot of the information you get from RealContacts is similar to what you might get if you were to meet-up at a party with everyone you know, and the conversation drifted onto job opportunities and which job might be right for which person. The key things that make RealContacts a much more efficient way of transferring this information are:

• You can find out not only about the jobs your direct contacts know about, but also about jobs their contacts know about, and so on out to contacts up to 4 degrees away from you.
• RealContacts shows details about a job position that someone telling you about a position they know about wouldn't be likely to know, because the information is coming directly from the source.
• RealContacts lets you see job opportunities without interrupting every other person in the chain.
• You can set up notification so that as soon as a job is posted in your network of contacts that matches your preferences you can find out about it, without having to repeatedly visit and search on the website.

These features make RealContacts an extremely efficient way to find out about job opportunities that never get advertised publicly. It is not a substitute for real life networking; it just allows information to flow more easily between people who already know and trust each other. By extending these links of trust, RealContacts connects people who don't know each other directly through the path of contacts they have in common, who can provide mutual endorsement or advice if asked.

The Future of RealContacts
In the future you will be able to do a wide range of things using RealContacts, not just find jobs or staff. Think of all the times you place a higher value on information from your trusted network than from the general public or companies you don't know, such as getting advice on good (and bad) products and services, building teams and consortiums for projects, and buying, selling, and trading goods and equipment, for example. We are keen to work with people and companies on these new applications. RealContacts is work in progress and we always welcome suggestions on how to improve the service. Please contact us with your thoughts and comments.

References (books, papers and websites)
Albert-László Barabási "Linked - The New Science of Networks" (Perseus Publishing, 2002)

Duncan J. Watts and Steven H. Strogatz, "Collective Dynamics of "Small-World" Networks," Nature 393, 440-442 (1998)

Malcolm Gladwell, "The Tipping Point," (Little, Brown, New York, 2000)

Mark Buchanan, "Nexus - Small Worlds and the Groundbreaking Science of Networks" (W.W. Norton and Company, 2002)

Mark S. Granovetter, "The Strength of Weak Ties," American Journal of Sociology 78, (1973) 1360-1380.

Stanley Milgram, "The Small-World Problem," Psychology today 1, 60-67 (1967).