2441 search results for "map"

Lahman: A New R Package for Baseball Stats

April 25, 2013
By
Lahman: A New R Package for Baseball Stats

by Joseph Rickert Baseball fans have been serious about statistics since Carl Pearson was a young man (although I doubt that Carl followed the game). It is not clear, though, exactly when baseball statisticians moved from doing descriptive stats into predictive analytics. In his book Super Crunchers, Ian Ayers credits Bill James of Baseball Abstract fame for getting this...

Read more »

Python Complements R’s Shortcomings

April 23, 2013
By
Python Complements R’s Shortcomings

I’m a big fan of open-source software for research. For example, R-statistics, Qgis, and Grass GIS are awesome programs. R can do any statistical tests and numerical modeling you can imagine; if there’s not a built-in function you can write … Continue reading →

Read more »

wapply: A faster (but less functional) ‘rollapply’ for vector setups

April 23, 2013
By
wapply: A faster (but less functional) ‘rollapply’ for vector setups

For some cryptic reason I needed a function that calculates function values on sliding windows of a vector. Googling around soon brought me to ‘rollapply’, which when I tested it seems to be a very versatile function. However, I wanted to code my own version just for vector purposes in the hope that it may

Read more »

Gridding data for multi-scale macroecological analyses

April 22, 2013
By
Gridding data for multi-scale macroecological analyses

These are materials for the first practical lesson of the Spatial Scale in Ecology course. All of the data and codes are available here. The class covered a 1.5h session. R code for the session is also at the end…Read more →

Read more »

Time Varying Higher Moments with the racd package.

April 22, 2013
By
Time Varying Higher Moments with the racd package.

The Autoregressive Conditional Density (ACD) model of Hansen (1994) extended GARCH models to include time variation in the higher moment parameters. It was a somewhat natural extension to the premise of time variation in the conditional mean and variance, though it probably raised more questions than it, or subsequent research have been able to answer.

Read more »

Time Varying Higher Moments with the racd package.

April 22, 2013
By
Time Varying Higher Moments with the racd package.

The Autoregressive Conditional Density (ACD) model of Hansen (1994) extended GARCH models to include time variation in the higher moment parameters. It was a somewhat natural extension to the premise of time variation in the conditional mean and variance, though it probably raised more questions than it, or subsequent research have been able to answer.

Read more »

R et Twitter

April 22, 2013
By
R et Twitter

(This article was first published on Learning Data Science , and kindly contributed to R-bloggers) On va dans ce post, illustrer une utilisation simple des packages twitteR, StreamR, tm qui permettent faire du textmining. En réalité, les deux premiers permettent de récuperer les tweets et de faire des comptages simples et complexes et le dernier permet de faire du...

Read more »

Programmatically Download CORINE Land Cover Seamless Vector Data with R

April 21, 2013
By
Programmatically Download CORINE Land Cover Seamless Vector Data with R

Thanks to a helpful SO-Answer I was able to download all CLC vector data (43 zip-files) programmatically:require(XML)path_to_files dir.create(path_to_files)setwd(path_to_files)doc urls # function to get zip file namesget_zip_name # function to plug into sapplydl_urls # download all zip-filessapply(urls, dl_urls)# function for unzippingtry_unzip # unzip all files in dir and delete them afterwardssapply(list.files(pattern = "*.zip"),...

Read more »

Evaluating Event Impact Through Social Media Follower Histories, With Possible Relevance to cMOOC Learning Analytics

April 21, 2013
By
Evaluating Event Impact Through Social Media Follower Histories, With Possible Relevance to cMOOC Learning Analytics

Last year I sat on a couple of panels organised by I’m a Scientist’s Shane McCracken at various science communication conferences. A couple of days ago, I noticed Shane had popped up a post asking Who are you Twitter?, a quick review of a social media mapping exercise carried out on the followers of the

Read more »

Prioritizing project stakeholders using social network metrics

April 20, 2013
By
Prioritizing project stakeholders using social network metrics

Identifying project stakeholders and their requirements is a very important factor in the success of any project. Existing techniques tend to be very ad-hoc. In her PhD thesis Soo Ling Lim came up with a very interesting solution using social network analysis and what is more made her raw data available for download I have

Read more »