http://oracleofbacon.org/

The Six degrees of separation refers to the idea that, if a person is one step away from each person he or she knows and two steps away from each person that their first person knows, then everyone is an average of six steps away from each person on Earth. This phenomena was pioneered by Guglielmo Marconi. Marconi attempted to compute how many radio relay stations were required to cover the globe. He came up with an average of 5.83.

The University of Virginia wanted to test the six degrees of separation theory by determining whether any actor can be linked through his or her film roles to actor Kevin Bacon. In the early 1990’s this became a very popular game on college campuses across the country. This type of game has also been created in the mathematical world but instead of actors having bacon numbers, mathematicians get an Erdos number depending on how many papers they wrote with Paul Erdos

Many students look to the Greek system at their schools in order to meet such desires because fraternities foster brotherhood, friendship, and help to meet new people and establish relationships. However, many fraternities are recognized or distinguished from others by a particular characteristic of its members. Prime examples are divisions by race, religion, ethnicity, sports, and personality. For example, when a varsity soccer player pledges a fraternity, he convinces all of his friends to pledge there as well. As more soccer players pledge and get initiated into the fraternity, people eventually associate it with the similar athletic status of its members. The principles of homophyly and segregation facilitate the homogenizing of fraternities because the same types of people pledge those fraternities.

Information cascades contribute to this phenomenon because students will pledge the fraternity they feel fits them the best. They receive their private information from people who they have connections to, and these people are their friends, who they have more in common with from the beginning. Thus, they receive high signals from the same group of people: the group with which the fraternity is identified.

In addition, the already established status of the fraternity will discourage others who would not fit into it from joining. For instance, in a Jewish fraternity, the Jewish presence may intimidate non-Jewish students and dissuade them from rushing/pledging. The article, titled “Greek like still segregated at University of Alabama,” discusses how the fraternities are having a difficult time integrating members of different races into different fraternities. What the article states as “students…joining the organizations in which they feel most comfortable,” the students are merely joining the fraternity where they think that they will be part of the majority. When a fraternity is entirely composed of black members, others may feel less inclined to pledge because they will be in the minority and may be concerned that they may feel distant from the rest of the students.

http://findarticles.com/p/articles/mi_m0DXK/is_17_19/ai_9280020

            A number of issues in the modern world have the capacity to severely change society, or even civilization as a whole. The threat of terrorism and nuclear warfare, severe overpopulation, and recent climate change are all extremely fragile subjects that modern man will be required to confront sooner than later in order to continue advancing positively.  In particular, the problem that we are best suited to remedy is the issue of global warming. Over the past few years especially, enumerable advances in modern sustainable technologies have been made, but not yet implemented for reasons largelyrelated to policy control and lack of governmental/social interest. If change is in the future, it is going to have to be accepted by a powerful and demanding network of individuals.

There are many other ways to stimulate sustainability awareness, thereby inducing an information/interest cascade in sustainable technologies. For example, the government should enforce much more emissions/energy efficiency standards than what are currently in place. With any luck, the outcome of the 2008 election will favorable put America in the right direction for this. Secondly, the government should offer rebates to Americans for investing in sustainable technologies. When you buy a sustainable car, or put solar panels on your house, etc. there should be tax write-offs available. Nothing will motivate people more than essentially getting “free money.” But really, this money isn’t free. It is essentially an investment that can help pull us out of our oil dependence and stimulate the American manufacturing market with a new rise of American developed sustainability technologies, potentially pulling us out of a near recession. Pro-sustainability commercials should be made, and, also, perhaps a Michael Moore type documentary could motivate the young-college generation to take policy change into their hands. This generation will need to stop climate change if it is going to be effectively defeated.

http://www.ucsusa.org/global_warming/

I’m no expert, but I know that when it comes to choosing a type of vehicle to drive, a lot of different factors are considered.  Safety and fuel efficiency are probably two of the largest deciding factors. 

Is it more economical to drive a gas-guzzling vehicle or purchase a brand new fuel-efficient car?  According to a commuting cost calculator (http://mpggenie.com/), back when gas prices were under $3 per gallon, if you were to commute 50 miles/day, 5 days/week driving an Dodge Durango, you could accumulate gas expenses of $3,000 a year.  If you were to do that same commute in a Toyota Prius, you would only be spending $600/year on gas and could be using that $2400 savings on a down payment for a new Prius. 

Obviously if you were only looking at cost savings alone, you would choose a smaller more fuel-efficient car over an SUV.  However, if you were looking to purchase a vehicle based on safety, you might buy an SUV instead.  Here is a video of a crash test that shows what can happen when an SUV collides with a smaller vehicle: http://www.youtube.com/watch?v=JXeKSDpFjlg

As I’m sure you have probably guessed, the results are not good for the passengers in the car.  When a mismatch of car type occurs in a collision, the car whose center of gravity is higher will sustain less damage than the lower-riding vehicle.  Between difference in height and difference in weight of the vehicles involved, a car would be crushed and the results to its passengers would be fatal, whereas the larger vehicle and its passengers would turn out much better off. 

Relating this back to the Hawk-Dove game, I would label the SUV as the hawk, the car as the dove, and the payoff matrix would be the same.  In a car vs. car situation, the payoffs would both be 1.  The drivers would be happy because they are saving money on gas and if they were to get into an accident, it wouldn’t be too severe because they are of the same vehicle type.  In an SUV vs. SUV situation, the payoffs would both be ½ because they are of the save vehicle type and so a collision wouldn’t be terribly damaging to either vehicle, however they are each paying a lot for gas, giving them a lower payoff than the car vs. car scenario.  However, when you put a car up against an SUV, the car doesn’t have a fighting chance.  If a collision were to occur, the car would be demolished (payoff of 0) and the SUV would come out practically unscathed (payoff of 2 for being smart enough to have selected a safer vehicle).  This link shows pictures of an SUV-car collision.  (http://retardzone.com/2007/06/13/suv-vs-compact/)

Although we would like to believe that the rising gas prices would deter consumers from purchasing and continuing to drive SUV’s, as long as they are still on the road, it is unsafe for smaller vehicles.  Thus, driving a smaller car is not evolutionarily stable.  That’s something scary to think about.

Recently officials in New York have developed a new method to solve cases that have stumped law enforcement for years.  Inmates in fifty-eight county jails across the state will receive playing cards with pictures of people who are missing in hopes of finding information about what happened to these people.  The story can be read at http://www.reuters.com/article/oddlyEnoughNews/idUSN0136128320080501. 

Investigators are hoping that by starting their search at “the source of the crime” they will be able to find prisoners who have information about the crimes that may have been committed against these missing people.  The idea is that because of the small-world phenomenon where everyone is linked by “short chains of acquaintances” those who are incarcerated will be able to provide information about these cold cases that others could not.  The investigators have exhausted all other leads, trying to come up with an answer starting with the “small-worlds” of the victims, but they are coming up empty-handed.  By distributing these playing cards investigators will be able to begin their search from the other end of the chain, starting with the “small-world” of the prisoners and working their way out, hopefully to the victims.  This idea inherently makes sense, because those who have committed crimes likely associate with others who have committed crimes or spent a lot of time in places where crimes may have been committed.  This makes those who are incarcerated great sources for information about these missing people.  They have contacts within and outside of the criminal world and may be able to use these contacts to help law enforcement close their cases.

In a NY Times article, Kenneth Arrow, a Nobel laureate and Stanford professor suggests that how much you get paid depends on the number of connections you have, rather than your technical skills. He argues that if labor markets are truly efficient, then there would not be such a significant gap in income between workers with similar skills and credentials. He claims that properties such as intelligence, education, experience, and age are only account for half of that income gap. The other half is related to the number of connections that an employee has.

Arrow formulates a model that views employees’ wages as a function of competitive bidding among companies, rather than a typical function of supply and demand. It turns out that companies bid more aggressively for workers of whom they have favorable personal information about, such as their sense of humor or how reliable they are. This personal information is usually conveyed through personal contacts between the employee and someone in the company. Hence, the more connections a prospective employee has, the more likely it is that more companies obtain this information, thus increasing the bid amount.

Using this model, Arrow estimates that a worker with one connection would expect to earn $19,570, while five connections would earn $30,410. How does this stack up when compared to actual job statistics? Looking at workers in 1998 between 24 to 40 years old, whose highest level of education was high school, the average income for African-American workers was $26,223, while the average income for whites was $33,123. Using Arrow’s model, this would mean that the average African-American worker had connections to 3.2 companies, while the average white worker had connections to 5.7 companies. If this could be measured in some way, then perhaps this model can account for the wage gap. This effect however, is much weaker when it comes to jobs that require higher education and technical skills.

Sources:

http://query.nytimes.com/gst/fullpage.html?res=9A04E2DC163EF931A1575BC0A9629C8B63&sec=&spon=&pagewanted=1

UIL allows questionable ’stacking’ in tennis

Game theory, the idea of choosing between strategies offering different payoffs considering the actions of other players, is a common phenomenon in our lives. We can hardly go through a day without witnessing its ubiquitous effects.

In a dual team tennis match with x players on each team, the ideas of game theory, Nash equilibrium, and pure/mixed strategies become manifest through the art of competitive play. The two coaches of each team devise a lineup beforehand, seeding the players from 1,2,3…x. Often times, coaches are inclined to place their best player at No.1, their second best player at No.2, and so forth. However, a variety of factors including style of play, health conditions, depth of the opponents’ roster, and the perceived competitiveness of the match may frustrate coaches when devising a winning lineup.

When coaches are placed in a situation with little regulation and, optimal probabilities can be obtained by randomizing pure strategies. In their article “…How to form political slates and tennis teams”, Jonathan Hamilton and Richard E. Romano suggest that the best idea is to randomize strategies. For a tennis team, this means that the coach should assign players so that each player on the team has the same probability of playing on the No.1 spot, No.2 spot, etc. The other team sees equal payoffs for all scenarios, as there is an equal chance that any one of the other team’s players could be playing at the No.1 seed. Thus, there is no reason for the coach to choose any particular player himself to play No.1, and the second team chooses to play mixed pure strategies with equal probabilities as well. When this occurs, Hamilton and Romano state that the Nash equilibrium now becomes a mixed strategy with equal probabilities of any match-up, a phenomenon known as “Pure Strategy Equilibrium (PSE)”.

Several instances of PSE have occurred in tennis leagues across the country, as show in the article. The Galveston County Daily News recently reported that several class 4A and 5A high school tennis teams in Texas have removed player numbering in their leagues. Dual team matches “will have the same win 10 individual matches, win the overall dual match concept, but with an added twist-no true lineup.” This new format creates the type of payoff matrix where PSE occurs. Assuming 10 slots for individual player matches, each can choose any combination of players to fill slots 1-10 but they do not know if the other coach is playing Sincere or using some other Insincere combination of players. Thus, there is no incentive with this game format except to randomly select players to fill up the 10 spots.

Marketing professionals have been interested in Word of Mouth communications and the spread of information about products and services since the early 1960’s.  More importantly, these professionals are concerned with the influence these communications have on the social networks in which they occur.  The evolution of Word of Mouth techniques has led to a new tactic which is utilized by many different companies in many different industries known as buzz marketing.  Buzz marketing involves passing on information about a product, service, or idea to social leaders in a social network, who become known as buzz agents.  Social leaders are, more or less, popular people or people with influence in a social network; leaders that people look up to and whose opinions they trust because they are often early innovators.  Because of the infiltration of the social network through social leaders, the thinking is that the support for the product, service, or idea will penetrate the network through a ripple effect.  Buzz marketing is looked upon by society in different ways, and it raises some ethical dilemmas for the companies practicing buzz marketing and for the social networks it is being implemented in.  The market for the practice of buzz marketing is only increasing, as some small firms who specialize in implementing buzz market plans for large corporations are being hired by more and more companies who are looking to reap benefits from buzz marketing.  As a marketing practice, buzz marketing is the most concentrated and most effective at penetrating social networks of any size, but it is important that companies using buzz marketing practice it ethically.

Chapter 1 of “Networks,” the Econ 204 course packet, deals with social networks and explains how distances are measured within networks.  If a company is a singular node in a social network, then in the case of buzz marketing, all buzz agents, which are the points immediately connected to the company, would have a distance to the company of one.  All people who have learned about the company directly from a buzz agent have a distance to the company of two, and so on throughout the network.  The major idea behind buzz marketing, or its ultimate goal, is to increase the awareness of the company and its product, service, or idea to the farthest distance possible, while only spending the resources to reach the people in the network with distance one, the buzz agents themselves. 

Below is a link to an article by Jim Matorin which talks about buzz marketing where a lot of the information for this post was learned:

http://wf2dnvr4.webfeat.org/MilrJ1192/url=http://www.lexisnexis.com/us/lnacademic/auth/checkbrowser.do?ipcounter=1&cookieState=0&rand=0.7248017169825984&bhjs=1&bhqs=1

The idea of chemistry is often used to describe players’ interactions on and off the court in the world of sports.  In its context, it is in an organization’s best interest to bring in players who will find the best “chemistry” amongst themselves in order to win a championship.  In reality, promoting chemistry on sports teams is simply maintaining structural balance in a network of people.

In class, we learned about structural balance with examples of triangles.  In a triangular social balance, each triangle of three nodes must have one or three positive edges.  A positive edge indicates that the two nodes like each other, while a negative edge indicates dislike between the two nodes. 

In arguably the largest scale example of what happens when a team becomes structurally unbalanced, Shaquille O’Neal and Kobe Bryant, two of the greatest basketball players of our generation, grew to dislike each other and lost their “chemistry” on the basketball court.  The organization, the Los Angeles Lakers, valued these two great players both tremendously.  They had won championships together and made the franchise an annual championship contender.  Each of the players respected the organization and its decisions, but when they grew to dislike each other, things began to fall apart.  It could be said that positive edges existed between the Lakers organization and each of Bryant and O’Neal.  While a positive edge existed between O’Neal and Bryant, the Lakers won three championships.  Once the animosity between the two All-Stars grew to the point of a negative edge between them, things dramatically changed in the Lakers franchise. 

The negative edge that grew between Bryant and O’Neal was one of the most documented disagreements between teammates in recent history.  The duo that had been the nucleus that helped the Los Angeles Lakers “three-peat” in 2000, 2001, and 2002, had disintegrated, and both stars decided L.A was only big enough for one of them.  Eventually, the disruption caused O’Neal to be traded to the Miami Heat. 

Generally, teams that win championships in professional sports are said to have the best chemistry on the court, ice, or field.  While Bryant and O’Neal got along, their team flourished and won three NBA championships in a row.  Once they had their well documented falling out, the L.A Lakers were not the same team, and have not returned to their championship status since O’Neal left. 

A link to the article “A Partitioning Approach to Structural Balance” is attached below:

http://www.sciencedirect.com/science?_ob=ArticleURL&_udi=B6VD1-3VW1DVP-3&_user=10&_rdoc=1&_fmt=&_orig=search&_sort=d&view=c&_acct=C000050221&_version=1&_urlVersion=0&_userid=10&md5=7f620cd150cf73a035e54285166ae7a8

As an employee of Campus Information and Visitor Relations here at Cornell University, I have noticed that the job that we students perform is, in reality, to act as gatekeepers for the university itself and provide a local bridge between people who wish to know more about the campus and the information they seek.  Our job at CIVR is basically tri-faceted; we work the information desk in Day Hall, we work the phones for the general university switchboard (254-INFO), and most visibly, we guide the campus tours for prospective students, parents, and other visitors.  At each of these different positions, we act as these “university gatekeepers.” 

When people call in to the general university switchboard, their requests can range from finding information on when tours are to finding information for people on campus and from requests of viewbooks and packets to really obscure questions about things that can only be answered by people in the department specific to the question.  It is part of our training that when we are on the phone we say to people, “I’ll connect you…” rather than “I’ll transfer you…” and we are truly connecting them with the information or person they desire or to the person who will be able to better answer their question.  Part of our and any gatekeeper’s responsibilities are to connect one person (or node) to another. 

At the information desk, employees aid in connecting people to destinations inside of Day Hall to find things they are looking for.  Often, we direct people to the office of the Bursar, the Registrar, or the department of Human Resources.  The desk itself acts as the gatekeeping node between people entering the building and the different offices inside Day Hall.

Finally, as tour guides, student employees of Campus Information and Visitor Relations are the gatekeepers to providing all those on our tours with a plethora of information about Cornell’s history, buildings, ideals, campus, athletics, and academics.  Seemingly hundreds of local bridges are formed between people on the tours and the information about Cornell on virtually every tour we give.  If Cornell University and all the information pertaining to it are viewed as an information network, then tour guides are surely the most visible gatekeepers in the network. 

At the homepage for Campus Information and Visitor Relations, civr.cornell.edu, it is possible to get an idea for the way we gather information about our network quickly in order to answer questions over the phone, at the desk, or after tours.  We are able to search through our people directory, department directory, a program called “Infobase,” and through “Google Cornell.”  Infobase is a program that has a collection of the most searched for information about certain things on campus, like package drop boxes, payphones, or student activities, and organizes them into a searchable and manageable way for people to use as a resource.  This program, along with our directories, allows us as employees to be connected to the entire Cornell information network so that we can act as gatekeepers. 

The link below describes gatekeepers in a network. 

http://proquest.umi.com.proxy.library.cornell.edu/pqdweb?index=0&did=1145080651&SrchMode=1&sid=1&Fmt=6&VInst=PROD&VType=PQD&RQT=309&VName=PQD&TS=1209695776&clientId=8424