Inspired by my thesis, I have been playing around with mapping tools over the past few days. While the maps showing the distribution of migrant groups across the United States did not make it to the final copy of my paper I had fun toying around with the various mapping ...

As you might remember from my blog post about ropenaq, I work as a data manager and statistician for an epidemiology project called CHAI for Cardio-vascular health effects of air pollution in Telangana, India. One of our interests in CHAI is determining exposure, and sources of exposure, to PM2.5 which ...

It’s not even Labor Day, so it seems to be a bit early to start planning for next year’s R conferences. But, early-bird pricing for RStudio::Conf 2018 ends this Thursday. The conference which will be held in San Diego between January 31st and February 3rd promises to match ...

Which is better: machine learning or statistics? Hopefully the way that question is phrased highlights its ridiculousness, but with all the hype around machine learning these days you’d be forgiven for thinking that machine learning is the answer to all data-related questions. However, statistics departments aren’t shuttering or ...

An arithmetic Le Monde mathematical puzzle (that first did not seem to involve R programming because of the large number of digits in the quantity involved): An integer x with less than 100 digits is such that adding the digit 1 on both sides of x produces the integer 99x.  What are ...

The R package seplyr has a neat new feature: the function seplyr::expand_expr() which implements what we call “the string algebra” or string expression interpolation. The function takes an expression of mixed terms, including: variables referring to names, quoted strings, and general expression terms. It then “de-quotes” all of ...

I recently had the honor of speaking at the 2017 American Community Survey (ACS) Data Users Conference. My talk focused on choroplethr, the suite of... The post Recording of my Talk at the ACS Data Users Conference appeared first on AriLamstein.com.

Suppose as a business manager you have the responsibility for testing and comparing the lifetimes of four brands (Apollo, Bridgestone, CEAT and Falken) of automobile tyres. The lifetime of these sample observations are measured in mileage run in ’000 miles. For each brand of automobile tyre, sample of 15 observations have been ...

Two hundred and twenty-four new packages were added to CRAN in July. Below are my picks for the “Top 40” packages arranged in eight categories: Machine Learning, Science, Statistics, Numerical Methods, Statistics, Time Series, Utilities and Visualizations. Science and Numerical Methods are categories that I have not used before. The idea ...

I was thinking a lot about proportional-odds cumulative logit models last fall while designing a study to evaluate an intervention’s effect on meat consumption. After a fairly extensive pilot study, we had determined that participants can have quite a difficult time recalling precise quantities of meat consumption, so we ...

By Yuri Fonseca Basic idea In this post we will discuss briefly about pricing optimization. The main idea behind this problem is the following question: As manager of a company/store, how much should I charge in order to maximize my … Continue reading →