Maxwell's Demon hosted Carnival of Mathematics #65. Here is #66.
If you're new to Carnival's or to this one, check out Mike Croucher's great introduction.
As is tradition, the Carnival host has to come up with interesting things to say about the number of the Carnival he or she is hosting. 66 factors into 2x3x11. Not very exciting, huh!?! Well, 66 is the number of 8-iamonds. This I learned from the "What's Special About this Number?" page. 66 is also a triangular palindromic number. And, there are 66 books in the bible. Thank you to this source for these last two facts. And, Star Trek's first year on TV was ... yup, 1966. Ok, time to get to the meat of the Carnival.
Cory at the Wolfram Blog submitted an article by Ed Pegg Jr, Remembering Martin Gardner. The article links to another article where Pegg Jr. tells of some of his early experiences with Martin Gardner's work. The second article starts with this interesting thought:
On May 22, 2010, Martin Gardner died, unexpectedly, at age 95. The previous sentence contains a paradox explained within his book The Unexpected Hanging and Other Mathematical Diversions, one of 15 books known collectively as “the Canon,” comprising hundreds of the Mathematical Games columns Martin wrote for Scientific American between 1956 to 1981.
Fëanor, at Jost A Mon, submitted The Socioeconomics of Toilet Seat Positioning. Yes, I do review articles! Fëanor's article has lots of equations in it. I think it's sincere And, if you read through to the end, it does make a recommendation on how to avoid the toilet seat ills.
Fëanor suggested I include Simpson's Paradoxical Card Trick by Rense at the Curving Normality blog. This article illustrates how "finding associations – with correct math! – in subsets, whereas this association is not present in the aggregated sets is so counter-intuitive, that we can easily make a mistake."
Sue at Math Mama Writes submitted Logarithms and Ropes (as found in Mathematician's Delight). Sue's article gives an interesting physical interpretation of how Napier might have come up with logarithms.
Tracy at the Dreambox Blog submitted Be Homework-Ready With This Math Kit! It's a nice little article that gives suggestions on things a parent might put into a "Math tool kit."
Jonathan at JD2718 gives us Unwrapping NYSED Regression - looking at a lesson and NYS Integrated Algebra 2/Trig: neat regression problem. The articles are about New York State education standards, plotting data, seeing (regression) patterns in the graphs, and how his students did with this.
I have to admit that my Calculus is pretty rusty but I still really liked Dave's Volumes of N-dimensional balls article over at Division by Zero. I wish that the calculus problems I got to solve in high school were as interesting as this one. There's a LOT of room for exploration with this problem. Plus, Dave graphs a VERY interesting property of the volumes of unit balls in n dimensions as n increases and even provides a geogebra applet to further student exploration.
Nancy submitted Math Monday: Nailbanger's Nightmare by George Hart for the Museum of Mathematics at Make Magazine. The author tells "In 1995, I designed this hypothetical construction and posted a computer rendering of it online. It is called "Nailbanger's Nightmare" because I thought it was far more complex than any carpenter would ever want to make." And then, a wonderful thing happened ...
John, at the Endeavour, writes about a Normal approximation to logistic distribution. John considers the logistic distribution and the normal distribution. He notes that their graphs look similar. And then he dives into this question: "But which normal distribution approximates a logistic distribution? That is, how should we pick the variance of the normal distribution?"
What does a Greek cow say? Patrick at Math Jokes 4 Mathy Folks reveals the answer to that gem and tells another joke, which happens to be my very favorite Math joke. And, he tells one more joke. Three fun jokes in one blog post. Check it out!
John (yes, another John) at Random Walks shares Really Fun Limit Problem (revisited) . It's a nice geometric exploration, complete with an applet to help in your investigation. It's a limit problem with a surprising result!