Recently I needed a simple example showing when application of regularization in regression is worthwhile. Here is the code I came up with (along with basic application of parallelization of code execution). Assume you have 60 observations and 50 expla...
A couple of years ago I implemented an automated trading algorithm for a strategy called the “Cable Morning Trade”. The basis of the strategy is the range of GBPUSD during the interval 05:00 to 09:00 London time. Two buy stop orders are placed 5 points above the highest high for this period; two sell stop
The following is a guest post from Joel Harrrison, PhD, consulting Aquatic Scientist.For a luddite like me, this is a big step – posting something on the inter-web. I’m not on Facebook. I don’t know what Twitter is. Hell, I don’t even own a smartphone. But, I’ve been a devoted follower of Myles’ blog for some time,...
It’s Memorial Day and my dissertation defense is tomorrow. This week I’m phoning in my blog. I had the opportunity to teach a short course last week that was part of a larger workshop focused on ecosystem restoration. A fellow grad student and I taught a session on Excel and R for basic data analysis.
Exploratory Data Analysis: Variations of Box Plots in R for Ozone Concentrations in New York City and Ozonopolis
Introduction Last week, I wrote the first post in a series on exploratory data analysis (EDA). I began by calculating summary statistics on a univariate data set of ozone concentration in New York City in the built-in data set “airquality” in R. In particular, I talked about how to calculate those statistics when the data
I am going to be using the party package for one of my projects, so I spent some time today familiarising myself with it. The details of the package are described in Hothorn, T., Hornik, K., & Zeileis, A. (1999). “party: A Laboratory for Recursive Partytioning” which is available from CRAN. The main workhorse of
Under the covers of strange bedfellows. Previously The idea of implied alpha was introduced in “Implied alpha — almost wordless”. In a comment to that post Jeff noticed that the optimal portfolio given for the example is ever so close to the minimum variance portfolio. That is because there is a problem with the example … Continue reading...
I was working with a small experiment which includes families from two Eucalyptus species and thought it would be nice to code a first analysis using alternative approaches. The experiment is a randomized complete block design, with species as fixed effect and family and block as a random effects, while the response variable is growth
I have had some work on CRAN stats on the back-burner but the recent article How R Grows tempted me to push it up the list In the interim, I have a couple of comments on Joseph Rickert`s article. Although the body of the article refers to packages either created or updated in a time