Archive for October, 2006

Farms & Cents = Borlaug & Yunus

Wednesday, October 18th, 2006

 Borlaug  Grameen Bank Borrower  Yunus 

The US Census Bureau has a Special Edition comparing data from 1915, 1967, and 2006 – when the US population was about 100, 200, and 300 million, respectively.  Aside from Wilson being president and John and Mary being the most popular names in 1915, what does it mean?

The table below shows how 8 factors compare relatively, using constant dollars and 1967 as a base.  Some are a surprise to me, e.g., we have a smaller percentage of the population being foreign-born today than in 1915.  The chart below illustrates how these 8 concerns weigh in relative to each other. 



In 1915 tuberculosis trumped everything.  The data suggests today our concerns (aside from war!) ought  to be milk prices over gas prices; aliens, legal and illegal but not extraterrestrial (too few or too many?); and not enough farms. 

Mohammad Yunus (autobiography) just won the Nobel Peace Prize - for developing micro-loans and starting the Grameen Bank helping Third-Worlders lift themselves by the boostraps – 12 years to the day of accepting the World Food Prize, created by another Nobel Peace Prize winner, Norman Borlaug (just published biography)- who founded the Green Revolution and probably saved the world from a Malthusian destiny.  In his 90s and still going strong, you can read and hear some of Dr. Borlaug’s views at an Ohio State University lecture.

Netflix Prize >> Hutter Prize, in terms of money

Thursday, October 5th, 2006

Hutter Medal     oh yeah 

A couple of months ago Marcus Hutter offered up to 50,000 euros for losslessly compressing the 100MB English wikipedia corpus better than the then 18MB record.  Since then there has been a 6.8% improvement, and counting – each 1% is worth 500 euros.

Now Netflix is offering $1,000,000 for the first person or team to publish an algorithm that can predict how a customer will rate a movie based on prior ratings 10% more accurately than their current algorithm.  Be warned, the training files are big. There have already been 20 valid prediciton files submitted in the last 24 hours, and over 6000 teams from 92 countries registered.  So hurry!

The movie with the most ratings: Batman batman

Update:  Within 1 week the Netflix algorithm (subject of 15 years of research) has been bested.

Update2:  Some have claimed that the problem gets exponentially harder as you drive toward 10%.  We are almost half way there in under 3 weeks!  If linear we should be done by Thansgiving – but even if exponential, we can forecast victory in about 3 months.

Expected time

Haraguchi = π Spigot

Wednesday, October 4th, 2006


A spigot algorithm pumps out digits one at a time and does not reuse the digits after they are computed.  In 1995 Stanley Rabinowitz and Stan Wagon produced a remarkable spigot algorithm for generating decimal digits of Ï€ (paper in pdf).  Today the remarkable Akira Haraguchi finished reciting 100,000 digits of Ï€ from memory – a world record.

Pi Spigot

You can use the Pi-Search Page to find the location of the digits of π within π.  For example, The string 3 occurs at position 9 counting from the first digit after the decimal point.  It looks like the following plotted on a log chart.

Pi Position