## Polish mine shaft math exercise

Today’s Math Estimation Exercise involves this short video. Estimate the maximum speed attained by the man as he hurtles through the mineshaft. Then estimate the precision of your estimate: [vimeo]26618119[/vimeo] BONUS EXERCISE: Estimate how much salt was removed from the section of the salt mine visible in this video.

## How now, warm cow [Podcast 50]

Heat loss from a cow — that’s the deal in this week’s Improbable Research podcast. SUBSCRIBE on Play.it, iTunes, or Spotify to get a new episode every week, free. This week, Marc Abrahams  —with dramatic readings by Daniel Rosenberg — tells about: Heat loss from a cow — Khan, Zahid A., Irfan Anjum Badruddin, G. A. Quadir, and K. N. Seetharamu (2006). ‘A Quick and Accurate […]

## Old sewer numerical method

Nowadays there are many methods for estimating the approximate cost of sewers. In 1922, this diagram showed the then-state of the art: The diagram appears in the book Sewerage and Sewage Treatment, by Harold Eaton Babbitt (published by John Wiley and Sons, New York,1922).

## Firing a shotgun to calculate the approximate value of π

This mathematics paper broadens the old definition of “a shotgun approach” to solving a problem: “A Ballistic Monte Carlo Approximation of π,” Vincent Dumoulin [pictured here], Félix Thouin, arXiv 1404.1499v2, April 8, 2014. (Thanks to investigator Marcus Sprenkel for bringing this to our attention.) The authors, at the University of Montreal, report: “We compute a […]

## Exploding Species: a disappointment

Readers of a certain temperament, who seek high levels of stimulation, may feel a bit deflated —led on, then let down by the title — upon learning that the monograph called “Exploding Species” is about counting the number of species. The study is: “Exploding Species,” Trevor Price [pictured here], Trends in Ecology & Evolution, Volume 11, Issue […]

## Guess Bayesian-Bayesian to invent extraterrestrial stats

Today’s convoluted statistics exercise: Use Bayesian statistical methods to estimate the probability that Bayesian statistical methods will be invented by life that arises elsewhere in the universe. BACKGROUND: The Physics arXiv blog explains everything you need to know to make this estimate: The Drake equation is one of those rare mathematical beasts that has leaked into […]

## Estimated toilet-flush substance’s journey

The Flush Tracker web site claims to: “[tell] you where your flush goes once it disappears down the toilet…. In which countries does it work? Flush Tracker is currently available in the UK, Ireland, South Africa and Poland.” The web site shows a moving image based on an “estimate” of where and how fast the […]