2603 search results for "GIS"

Statistical Practice in Epidemiology using R

April 26, 2011
By
Statistical Practice in Epidemiology using R

This is a long running course which usually takes place in Tartu, Estonia. This year we are hosting it at IARC in Lyon, France. The course is intended for epidemiologists and statisticians who wish to use R  for statistical modelling … Continue reading →

Read more »

A Tiny Model of Evolution

April 25, 2011
By
A Tiny Model of Evolution

I've always wanted to write a(n overly) simple model of evolution. The assumptions are minimalistic: only one species, for which each individual's genotype is represented as a one-dimensional real number, e.g. 7.4. Now, the fun stuff: I define a fu...

Read more »

Annotated Manhattan plots and QQ plots for GWAS using R, Revisited

April 25, 2011
By
Annotated Manhattan plots and QQ plots for GWAS using R, Revisited

Last year I showed you how to create manhattan plots, and later how to highlight regions of interest, using ggplot2 in R. The code was slow, required a lot of memory, and was difficult to maintain and modify.I finally found time to rewrite the code usi...

Read more »

R workshop in Hamilton, Ontario, May 24 and 25

April 25, 2011
By

John Fox will be teaching a two-day introductory R workshop at McMaster University in Hamilton, Ontario, on May 24 and 25. The workshop will largely be based on materials from Fox and Weisberg, An R Companion to Applied Regression, Second Edition (Sage, 2011). Further information about the workshop is available at: https://www.socialsciences.mcmaster.ca/registrations/john-fox-introduction-to-r/fg_base_view_p3. A few spaces in the workshop are reserved for non-McMaster attendees and made...

Read more »

intuitive visualizations of categorization for non-technical audiences

April 25, 2011
By
intuitive visualizations of categorization for non-technical audiences

For a project I’m working on at work, I’m building a predictive model that categorizes something (I can’t tell you what) into two bins. There is a default bin that 95% of the things belong to and a bin that the business cares a lot about, containing 5% of the things. Some readers may be

Read more »

Of Height and Speed in Tennis, or Fuzziness and Techiness in College

April 24, 2011
By
Of Height and Speed in Tennis, or Fuzziness and Techiness in College

I thought of this after reading this post and perhaps also this one, one the Cheap Talk blog. Here's the puzzle: in general, being tall does not make you slow; but among professional tennis players, the tall athletes do tend to be relativel...

Read more »

Dates in R and the First Day of the Month

April 23, 2011
By
Dates in R and the First Day of the Month

I spent some time this morning learning about how R thinks about dates in R. I found this website to be a useful guide.Imagine that your data are dates in a standard format and you want a vector o...

Read more »

Dates in R and the First Day of the Month

April 23, 2011
By
Dates in R and the First Day of the Month

I spent some time this morning learning about how R thinks about dates in R. I found this website to be a useful guide.Imagine that your data are dates in a standard format and you want a vector o...

Read more »

Measuring association using odds ratios

Measuring association using odds ratios

In my last two posts, I have used the UCI mushroom dataset to illustrate two things.  The first was the use of interestingness measures to characterize categorical variables, and the second was the use of binary confidence intervals...

Read more »

Common Data Creation Commands

April 19, 2011
By
Common Data Creation Commands

Here is a video tutorial where I go through some of the most commonly used commands in creating and manipulating data. As soon as I want to do more than just running a single regression, I use these commands more than any other set of commands (in som...

Read more »