Have you ever thought drawing your own butterfly? I came across the butterfly curve, which was discovered by Temple Fay. The butterfly curve is produced by a parametric equation where: x = sin(t) * (e^cos(t)-2cos(λt)-sin(t/12)^5) and y = cos(t) *...

Paul Alper writes: Surely you would like to comment on the amazing escalation in the anti-cheating tech world. I predict it will be followed by some clever software which makes it appear that the student enrolled is actually the one taking the exam. Reminiscent of the height of the cold war of counter weapons and […] The post Anti-cheating robots appeared first on Statistical Modeling, Causal Inference, and Social Science.

Win-Vector LLC‘s Nina Zumel wrote a great article explaining differential privacy and demonstrating how to use it to enhance forward step-wise logistic regression (essentially reusing test data). This allowed her to reproduce results similar to the recent Science paper “The reusable holdout: Preserving validity in adaptive data analysis”. The technique essentially protects and reuses test … Continue reading Using differential privacy to reuse training data

David Hogg writes: I thought this was either interesting or bunk—using online games to infer how various kinds of cognitive intelligence vary with age. I thought it might be interesting to you on a number of levels. For one: Are there really categories of intelligence and can these map onto online games? For another: How […] The post Cognitive skills rising and falling appeared first on Statistical Modeling, Causal Inference,…

In this week's Statbusters (link), we discuss two recent widely-shared articles, one on deaths while taking selfies, and the other on the gender gap in income among graduates of top-tier universities. The common element between these two pieces is a reductionist analysis that looks at the correlation between a single variable X and an outcome Y when the outcome Y is affected by a multitude of variables. For example, it…

Mon: Cognitive skills rising and falling Tues: Anti-cheating robots Wed: Mindset interventions are a scalable treatment for academic underachievement — or not? Thurs: Most successful blog post ever Fri: Political advertising update Sat: Doomed to fail: A pre-registration site for parapsychology Sun: Mars Missions are a Scam Also, don’t forget what’s on deck for the […] The post On deck this week appeared first on Statistical Modeling, Causal Inference, and…

I was recently talking with some SAS customers and someone started talking about generating random numbers. I was asked "Why can't SAS create an easy way to generate random numbers? Excel has a simple way to generate random numbers between 1 and 100, and I use it all the time." […] The post How to generate random integers in SAS appeared first on The DO Loop.

Principal-components regression (PCR) is routine in applied time-series econometrics.Why so much PCR, and so little ridge regression? Ridge and PCR are both shrinkage procedures involving PC's. The difference is that ridge effectively includes all...

Political scientist Brian Silver points me to his post by economist Paul Romer, who writes: The style that I [Romer] am calling mathiness lets academic politics masquerade as science. Like mathematical theory, mathiness uses a mixture of words and symbols, but instead of making tight links, it leaves ample room for slippage between statements in […] The post Flamebait: “Mathiness” in economics and political science appeared first on Statistical Modeling,…