Saturday, September 28, 2013

R User Group Sponsorship

Revolution’s 2014 R User Group Sponsorship Program Begins October 1st! If you are interested, have a look at:

Tuesday, September 24, 2013

Waiting in One Line or Multiple Lines

As a statistician, what is better, having a single queue or multiple queues, in regard with waiting time? Have a look at the following link:

Monday, September 23, 2013

Understanding Simpson's Paradox

When you look for overall trends, you often poke around the data in aggregate, but when you zoom out too far, you could miss details or within-category variation. Sometimes when you zoom in, you see a completely opposite trend of what you saw overall. This is known as Simpson's Paradox.

Monday, September 16, 2013

Unlawful primes

How small can a description of a large prime number be? 
If you have just zeros and two ones, then the only primes of that form are 11 and 101. If there are three ones then it is divisible by three. But what about four ones? Have a look at:

The Ultimatum Game

The ultimatum game was first presented to the research community in 1982 in an article entitled 'An Experimental Analysis of Ultimatum Bargaining'. The article discusses interesting results regarding the subjects' natural reactions and strategies for bargaining:

The Happiest Emoticons

Clearly, a :) is happier than a :( but what about a :-* and a :-D ? Or a :-| and a :-o ? In this post the author attempts to rank emoticons in order of how happy someone has to be to use each one:

A Lesson on Derivatives

"A Lesson on Derivatives” by Sungkon Chang featured in the October 2012 issue of The American Mathematical Monthly.

Medical Research is Better Because of Statistics

Friday, September 13, 2013

Only Load Data If Not Already Open in R

It is beneficial to check whether or not a dataset is already loaded into R at the beginning of a file. This is particularly helpful when you are dealing with a large file that you don't want to load repeatedly. Here is a way to do it:

Friday, September 6, 2013

Man Who Invented Modern Probability

It is oddly appropriate that a chance event drove Kolmogorov into the arms of probability theory, which at the time was a maligned sub-discipline of mathematics and was mocked at as "Theory of Misfortune". Kolmogorov presented a radical and, ultimately, foundational revision of probability theory using measure theory. 
For Kolmogorov, his ideas neither eliminated chance, nor affirmed a fundamental uncertainty about our world; they simply provided a rigorous language to talk about what cannot be known for certain.

The ROC curves of science

In practice, there is an inverse relationship between increasing rates of true discoveries and decreasing rates of false discoveries and that true discoveries from fields such as the biomedical sciences provide an enormous benefit to society. Few will deny that our current system, with all its flaws, still produces important discoveries. Want to find an optimal way out, the solution might be through ROC curves:

Also, here is Andrew Gelman's recent post on what he calls the "scientific mass production of spurious statistical significance":

Residuals from a logistic regression

What could be done with a graph of residuals, obtained from a logistic regression ?

John W. Tukey

“Statistics is a science in my opinion, and it is no more a branch of mathematics than are physics, chemistry and economics; for if its methods fail the test of experience – not the test of logic – they are discarded.”

Box plot, stem and leaf plot, ANOVA and, yes, even bit, software and vacuum cleaner are terms coined by John Wilder Tukey. Read more about him at

Interviews with Dennis Lindley

“Ultimately, in my extreme view, all reasoning reduces to probability calculations"

As a school student, Dennis Lindley had wanted to be an architect, but advice from his teachers led him to work on statistics instead. In communication with Helen Joyce, he offers a more personal description of his life as a Bayesian.

Monday, September 2, 2013

Is a Master’s degree in Statistics worthwhile?

If you care about understanding data.. Yes!!

A student who is considering a Master’s degree in Statistics asks, “I’m interested in finding a job in data analysis and have been looking around, but I’m not sure if a masters is necessary to break into the field”. Here is a discussion about the same

Global Wealth Inequality

Infographics showing an interesting aspect of World economy.