Yesterday I posted a very simple math puzzle to Twitter that I found in Jonathan Baron’s book, Thinking and Deciding. The puzzle is the following: Show that every number of the form ABC,ABC is divisible by 13. The puzzle comes up in Baron’s book as an example of an “insight problem” in which one goes
Posts Tagged ‘ mathematics ’
B*tchin’ six dimensional 6-cube. The rainbow colours and…
B*tchin’ six dimensional 6-cube. The rainbow colours and glass panes really help this visualisation. Examples of 6-dimensional things If it’s hard to envision 6 dimensions, consider this: the possible tunings of a guitar constitute a 6-dimensio...
B*tchin’ six dimensional 6-cube. The rainbow colours and…
B*tchin’ six dimensional 6-cube. The rainbow colours and glass panes really help this visualisation. Examples of 6-dimensional things If it’s hard to envision 6 dimensions, consider this: the possible tunings of a guitar constitute a 6-dimensio...
Easiest way to start imagining four-dimensional things is by…
Easiest way to start imagining four-dimensional things is by numbering the corners of a 4-cube. First realize that the eight corners of a cube can be numbered “in binary” 000—001–010–100—110–101–011—111. Just like the four corners of ...
Easiest way to start imagining four-dimensional things is by…
Easiest way to start imagining four-dimensional things is by numbering the corners of a 4-cube. First realize that the eight corners of a cube can be numbered “in binary” 000—001–010–100—110–101–011—111. Just like the four corners of ...
cumsum ( rnorm(50), lend="butt", lwd=12, type="h" ) Cumulative…
cumsum ( rnorm(50), lend="butt", lwd=12, type="h" ) Cumulative sum of 50 draws from a normal distribution. File this under mysteries of the Central Limit Theorem.
Central Limit Theorem A nice illustration of the Central Limit…
Central Limit Theorem A nice illustration of the Central Limit Theorem by convolution.in R: Heaviside 0,1,0) }HH
Here is how to improve your charts, graphs, maps, and…
Here is how to improve your charts, graphs, maps, and plots: Erase non-data ink. Erase redundant data ink. Maximize the ratio of data to ink. Show data variation, not design variation. The surface area of graphical elements should be directly proportio...
The Mule goes SURFing
A month ago I posted about “SURF”, the newly-established Sydney R user forum (R being an excellent open-source statistics tool). Shortly after publishing that post, I attended the inaugural forum meeting. While we waited for attendees to arrive, a few people introduced themselves, explaining why they were interested in R and how much experience they
Surf
A new R user group has launched in Sydney. It aims to bring together both experienced R users and complete beginners. The forum will meet monthly with talks on a wide range of subjects exploring all of the facets of this powerful tool.
Zero Inflated Models and Generalized Linear Mixed Models with R.
Zuur, Saveliev, Ieno (2012).
