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Where’s George?

I heard about this website Where’s George? that tracks the circulation of US dollar bills and other paper currency for fun. Since I am interested in networks and the flow of information, I decided to check it out.

You register a bill at the Where’s George? website by entering the denomination, series year, serial number, and your ZIP code. If you live outside of the United States, you can still participate by using the website’s list of global codes. Once you register a bill then…you spend it! If you want to increase the chance of having your bill being reported by someone, you can stamp the bill with information encouraging participants to visit the website and help track the bill’s journey.

Any person who receives your bill and decides to participate in tracking it enters the series year, serial number, and his or her local ZIP code on the Where’s George? website. This is known as a hit. Once a bill is registered, Where’s George? reports the time and distance traveled between hits, and any comments from the participants. Most bills do not receive any hits, but many bills receive two or more hits. Bills that are double- and triple-hitters are common, and some bills have 4 or 5 hits. After the participant enters the hit, then they, too, place the bill back into circulation by spending it.

Fans of the Where’s George? website often collect interesting patterns of hits such as getting at least one hit in all 50 states or getting hits on bills from all 12 Federal Reserve Banks. Fans can rank themselves for fun with their George Score. Your George Score is automatically calculated when you enter bills and get hits on Where’s George? The more bills you enter, and more importantly, the more hits you get, the higher your George Score. The George Score is a method of rating fans based on how many bills they have entered and also by how many total hits they have had. The formula is as follows:

100\times \left[{\sqrt  {\ln({{\rm {bills\ entered}}})}}+\ln({{\rm {hits}}}+1)\right]\times [1-({{\rm {days\ of\ inactivity}}}/100)]
However, since this formula is logarithmic it means that the more bills you enter and the more hits you receive, the less your score increases for each entered bill or new hit. Thus, your score does not increase as quickly when you enter a lot of bills. My George Score is 622.58 (for comparison, the top user has a George Score of over 1500). This makes my Where’s George? rank 6059 out of 16849. But my rank in my state is 277 out of 734.

Algorithm March And Ninjas

pythagora

I already mentioned in a previous post the Japanese kids’ show Pythagora Switch (Pitagora Suitchi, ピタゴラスイッチ) and their awesome Pythagorean devices (Pitagora Sōchi, ピタゴラ装置) made from various common household objects.

As if it couldn’t get any more awesome, the educational show also has a song and dance called the Algorithm March which really ramps up the awesomeness. The song and dance teach young children how to follow directions as they perform a sequence of body movements as they sing along with the song.

It is first performed by Kikuchi Hideki and Yamada Kazunari of the comedy duo Itsumo Kokokara. Then, they have guests such as soccer players, airline workers, and bus drivers performing the dance with them. Even ninjas! See the video clip below! The people line up and each person slowly moves forward while going through each body movement one at a time. The entire line goes through the sequence of steps (thus, algorithm march) as the song repeats.

The sequence of body movements are as follows, with the steps being repeated after finishing the sequence:

  1. One step forward, bend knees while reaching out with arms straight and then return
  2. One step forward, lean back with arms bent back and then return
  3. One step forward, turn around and bow once at waist
  4. Face left, right hand to brow and look around
  5. Face left, one step forward and bend knees, do a breast stroke and return
  6. Bend down and pretend to pick up a chestnut on the ground
  7. One step forward, move arms up and down like you are using a bicycle pump
  8. One step forward, flap arms at sides as if being inflated by the pump

When the entire line properly goes through the sequence of steps, each person becomes intercalated with the people ahead and behind him or her in a fascinating way that reminds me of clockwork or an assembly line:

If the above video clip doesn’t work, click here to view the video or click on the image below:

algorithm

Obviously, everyone needs to follow the correct sequence of intructions for the Algorithm March to work. So, that is where the algorithm comes in.

Al Gore playing drums

Al Gore rhythm! Get it? Nevermind…

The word algorithm comes from the ninth-century Persian scholar Al-Khwārizmī (Abū ʿAbdallāh Muḥammad ibn Mūsā al-Khwārizmī, عَبْدَالله مُحَمَّد بِن مُوسَى اَلْخْوَارِزْمِي‎). Al-Khwārizmī means native of Kharazm, a city now in modern Uzbekistan. Al-Khwārizmī wrote a treatise in Arabic describing the rules for performing arithmetic using Hindu-Arabic numerals as well as for solving linear and quadratic equations.

His arithmetic technique was called algorism when his work was translated into Latin and it was the Latinized form of Al-Khwārizmī. Incidentally, the word algebra is also from Al-Khwārizmī. It is from al-jabr, one of the ways he used to solve quadratic equations. His name is also the origin of the Spanish guarismo, meaning digit.

The Center for Elementary Mathematics and Science Education at the University of Chicago has a series of videos from their Everyday Mathematics program. This program is a comprehensive Pre-K through grade 6 mathematics program developed by the University of Chicago School Mathematics Project. The videos demonstrate the use of algorithms in performing the basic arithmetic functions.

Since an algorithm is a step-by-step solution to any problem, they are useful in areas beyond mathematics and computation.

You can express an algorithm either as a sequence of instructions:

South Park Gnomes

The gnomes’ business plan.

Or as a flowchart:

Flowchart for the Rock-Paper-Scissors game.

Flowchart for the Rock-Paper-Scissors game.