I am looking at the following tickers from 2005-01-01 to 2008-01-01. The tickers are GE, F, MSFT, DELL, INTC. I will find the mean-variance weights and the R-ratio weights and then test portfolio performance from 2008-01-01 to 2010-01-01. This is a … Continue reading → [Read more...]

This is a guest post by Edwin Thoen Currently I am doing my master thesis on multi-state models. Survival analysis was my favourite course in the masters program, partly because of the great survival package which is maintained by Terry Therneau. The …Read more » [Read more...]

R and Python have different strengths. There's little you can do in R you absolutely can't do in Python and vice versa, but there's a lot of stuff that's really annoying in one and nice and simple in the other. I'm sure simulations can be run in R, but it ... [Read more...]

A few days ago I came across Jack Heinemann and collaborators’ article (Sustainability and innovation in staple crop production in the US Midwest, Open Access) comparing the agricultural sectors of USA and Western Europe‡. While the article is titled around the word sustainability, the main comparison stems from the use ... [Read more...]

I showed an example of Extending Commodity time series back in 2012. Since then, the web site that I used to get the Thomson Reuters/Jefferies CRB Index data is no longer working. But there are a few alternatives: Thomson Reuters / Jefferies CRB Index. To get data, first select “TRJ/CRB ... [Read more...]

Using R and Integer Programming to find solutions to FlowFree game boards What is FlowFree?A popular game (iOS/Android) on a square board with simple rules. As the website states: Connect matching colors with pipes to create a flow. Pair all color... [Read more...]

Akaike’s Information Criterion (AIC) is a very useful model selection tool, but it is not as well understood as it should be. I frequently read papers, or hear talks, which demonstrate misunderstandings or misuse of this important tool. The following points should clarify some aspects of the AIC, and ... [Read more...]

Thank goodness, I think that even if this statistician business turns out badly, I can still make a living with rafting (if only by begging for money, in exchange for looking ridiculous in the swim suit)... As part as my brother's stag do, we went... [Read more...]

For some time now, I’ve advocated for the view that non-life loss reserving constitutes a categorized linear regression. I’ll emphasize that the idea of a linear regression isn’t remotely novel. Further, the categorization is the de facto approach. I’m merely recognizing it and suggesting instances where ... [Read more...]

The new R Journal is out! Click for a complete table of content with links to all papers. [Read more...]

In his book Quantum Computing Since Democritus, Scott Aaronson poses the following question: Suppose that you’re at a party where every guest is given a hat as they walk in. Each hat has either a pineapple or a watermelon on top, picked at random with equal probability. The guests ... [Read more...]

In case you missed them, here are some articles from June of particular interest to R users: You can create a Word document from a template and an R script with the R2DOCX package. Joe Rickert reviews books and other resources for learning about time series analysis in R. ... [Read more...]

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In our previous webinar, we discussed on predictive analytics and basic things to perform predictive analysis. We also discussed on an eCommerce problem and how it can be solved using predictive analysis. In this post, I will explain R script that I used to perform predictive analysis during webinar. Before ... [Read more...]

In R, objects of most types are supposed to be treated as “values”, that do not change when other objects change. For instance, after doing the following: a [Read more...]

LOYALTY PROGRAM CHOICE BASED ON DEPARTURE COUNT If you read Decision Science News, you’re probably a professor or grad student or researcher or policy type who flies around a lot to conferences, symposia, workshops, tutorials, summer schools, and all-hands meetings. You travel the globe to give talks and work ... [Read more...]

I recently presented about the mechanics of data visualization at the CLaRI Literacy Conference to a group of researchers, teachers and school administrators. The presentation is based on the work of Few (2012; 2009). While the presentation itself is not about … Continue reading → [Read more...]

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A paper published today in The R Journal discusses a fundamental limitation affecting reliability and reproducibility of R code. It explains how lack of dependency versioning causes R based applications break down, Sweave documents to stop working and CRAN to hit scaling problems. The paper suggests several solutions inspired by ... [Read more...]

Lately, I have been working with finite mixture models for my postdoctoral work on data-driven automated gating. Given that I had barely scratched the surface with mixture models in the classroom, I am becoming increasingly comfortable with them. With this in mind, I wanted to explore their application to classification ... [Read more...]