Robin Edwards, a researcher at UCL CASA, has created th […] [Read more...]

Another of the all ye entering here. Issue When subscripting an xts object, columns that don’t exist in the object are silently ignored. Example First, create an xts object: xtx xtx a b c 2014-02-07 1 11 21 2014-02-08 2 12 22 2014-02-09 3 […] The post An xts R Inferno-ism appeared first on ... [Read more...]

[This article was first published on Digithead's Lab Notebook, and kindly contributed to R-bloggers]. (You can report issue about the content on this page here) Want to share [Read more...]

As we all know, there are a lot of packages provide functions to plot maps, such as ggmap, GEOmap, rworldmap and so on. For visualizing 2D topographic map, here is a good example. Besides, 3D topographic map is also easily to be plotted via some excellent functions and packages. The ... [Read more...]

I spent a lot of time this week writing a short tutorial on knitr: knitr in a knutshell. This is my third little tutorial. (The previous ones were a git/github guide and a minimal make tutorial.) I’m pleased with these tutorials. In learning new computing skills, it can ... [Read more...]

Dealing with proportion data on the interval $[0, 1]$ is tricky. I realized this while trying to explain variation in vegetation cover. Unfortunately this is a true proportion, and can’t be made into a binary response. Further, true 0’s and 1’s rule out beta regression. You could arcsine square root transform ... [Read more...]

In both research and application, we need to manipulate data frames by selecting desired columns, filtering records, transforming and aggregating data. R provides built-in functions for data frame manipulation. Suppose df is the data frame we are dealing with. We use df[1:100,] to select the first 100 rows, df[,c("price","... [Read more...]

Following the exciting and innovative talks, posters and discussions at MCMski IV, the editor of Statistics and Computing, Mark Girolami (who also happens to be the new president of the BayesComp section of ISBA, which is taking over the management of future MCMski meetings), kindly proposed to publish a special ... [Read more...]

by Joseph Rickert The weather is on everybody's mind these days: too much ice and snow east of the Rockies and no rain to speak fo in California. Ram Narasimhan has made it a little easier for R users to keep track of what's going on and also get a ... [Read more...]

Including a series of dummy variables in a regression in R is very simple. For example,ols |t|) (Intercept) 10.9244 3.3607 3.251 0.00122 ** Time 8.7505 0.2218 39.451 [Read more...]

Random Forests are awesome. They do not overfit, they are easy to tune, they tell you about important variables, they can be used for classification and regression, they are implemented in many programming languages and they are faster than their competitors (neural nets, boosting, support vector machines, ...)Let us take ... [Read more...]

I’ve been calculated my day of 10,000 days old birthday in R since few days ago. I found that to calculate this in R is quite simple. My birthday to 10,000 days old birthday: Birthday to days since my birthday:…Read more › [Read more...]

One of the toughest problems in predictive model occurs when the classes have a severe imbalance. We spend an entire chapter on this subject itself. One consequence of this is that the performance is generally very biased against the class with the smallest frequencies. For example, if the data have ... [Read more...]

Guest post by Matt Sundquist of plot.ly. Plotly is a social graphing and analytics platform. Plotly’s R library lets you make and share publication-quality graphs online. Your work belongs to you, you control privacy and sharing, and public use is free (like GitHub). We are in beta, and ... [Read more...]

In serveral previous posts I have posted shiny applications which temporarily store data on shiny servers such as hit counters or the survey tool which I created,  These do not work in the long term since shiny will restart its servers without war... [Read more...]

Today I was putting some code together that made plots from slices of a 3-dimensional array object aa. A couple of the dimensions in aa had names defined by named vectors. For example:

<span>></span><span> aa </span><span>=</span><span> array</span><span>(</span><span>runif</span><span>(</span><span>2</span><span>*</span><span>3</span><span>*</span><span>4</span><span>),</span><span> <br>             dim</span><span>=</span><span>c</span><span>(</span><span>2</span><span>,</span><span>3</span><span>,</span><span>4</span><span>),</span><span> <br>             dimnames</span><span>=</span><span>list</span><span>(</span><span>id  </span><span>=</span><span> c</span><span>(</span><span>good</span><span>=</span><span>'id1'</span><span>,</span><span> evil</span><span>=</span><span>'id2'</span><span>),</span><span> <br>                           x   </span><span>=</span><span> c</span><span>(</span><span>1</span><span>,</span><span>2</span><span>,</span><span>3</span><span>),</span><span> <br></span><span>var</span><span> </span><span>=</span><span> c</span><span>(</span><span>up</span><span>=</span><span>'a'</span><span>,</span><span> dn</span><span>=</span><span>'b'</span><span>,</span><span> lt</span><span>=</span><span>'c'</span><span>,</span><span> rt</span><span>=</span><span>'d'</span><span>)))</span><span><br></span><span>></span><span> str</span><span>(</span><span>aa</span><span>)</span><span><br> num </span><span>[</span><span>1</span><span>:</span><span>2</span><span>,</span><span> </span><span>1</span><span>:</span><span>3</span><span>,</span><span> </span><span>1</span><span>:</span><span>4</span><span>]</span><span> </span><span>0.0138</span><span> </span><span>0.2942</span><span> </span><span>0.7988</span><span> </span><span>0.3465</span><span> </span><span>0.8751</span><span> </span><span>...</span><span><br></span><span>-</span><span> attr</span><span>(*,</span><span> </span><span>"dimnames"</span><span>)=</span><span>List</span><span> of </span><span>3</span><span><br></span><span>..</span><span>$ id </span><span>:</span><span> </span><span>Named</span><span> chr </span><span>[</span><span>1</span><span>:</span><span>2</span><span>]</span><span> </span><span>"id1"</span><span> </span><span>"id2"</span><span><br></span><span>..</span><span> </span><span>..-</span><span> attr</span><span>(*,</span><span> </span><span>"names"</span><span>)=</span><span> chr </span><span>[</span><span>1</span><span>:</span><span>2</span><span>]</span><span> </span><span>"good"</span><span> </span><span>"evil"</span><span><br></span><span>..</span><span>$ x  </span><span>:</span><span> chr </span><span>[</span><span>1</span><span>:</span><span>3</span><span>]</span><span> </span><span>"1"</span><span> </span><span>"2"</span><span> </span><span>"3"</span><span><br></span><span>..</span><span>$ </span><span>var</span><span>:</span><span> </span><span>Named</span><span> chr </span><span>[</span><span>1</span><span>:</span><span>4</span><span>]</span><span> </span><span>"a"</span><span> </span><span>"b"</span><span> </span><span>"c"</span><span> </span><span>"d"</span><span><br></span><span>..</span><span> </span><span>..-</span><span> attr</span><span>(*,</span><span> </span><span>"names"</span><span>)=</span><span> chr </span><span>[</span><span>1</span><span>:</span><span>4</span><span>]</span><span> </span><span>"up"</span><span> </span><span>"dn"</span><span> </span><span>"lt"</span><span> </span><span>"rt"</span>

Thus, I could access “aliases” for dimension names in id and var by:

<span>></span><span> names</span><span>(</span><span>dimnames</span><span>(</span><span>aa</span><span>)</span><span>$id</span><span>)</span><span><br></span><span>[</span><span>1</span><span>]</span><span> </span><span>"good"</span><span> </span><span>"evil"</span><span><br></span><span>></span><span> names</span><span>(</span><span>dimnames</span><span>(</span><span>aa</span><span>)</span><span>$var</span><span>)</span><span><br></span><span>[</span><span>1</span><span>]</span><span> </span><span>"up"</span><span> </span><span>"dn"</span><span> </span><span>"lt"</span><span> </span><span>"rt"</span>

The code ... [Read more...]

Well, I am tuning back in after a brief hiatus (what's a year-or-two-or-four between friends)?  Among other things, I just wrapped up a book for O'Reilly Media (Client-Server Web Apps with JavaScript and Java) due out in the Spring.   Please ... [Read more...]

Here is an example of a Histogram plot, with a stripchart (vertically jittered) along the x side of the plot.Alternatively, using the geom_rug function:Of course this simplicistic method need to be adjusted in vertical position of the stripchart or rug... [Read more...]

Geomorph users,We have uploaded version 1.1-6 to CRAN. The windows and mac binaries have been compiled and the tarball is available.The issue of the Mac OS X installers has been resolved. The problem stemmed from a dependancy (to JPEG), which was ... [Read more...]

In case you missed them, here are some articles from January of particular interest to R users: Princeton’s Germán Rodríguez has published a useful “Introduction to R” guide, with a focus on linear and logistic regression. The rxDForest function in the RevoScaleR package fits random forests of ... [Read more...]