Geomorph users,We have uploaded version 2.1.5 of geomorph* to CRAN. The windows and mac binaries have been compiled and the tarball is available.New Features:New Auto Mode allows users to include pre-digitized landmarks added to build.te...

After the Singapore Maths Olympiad birthday problem that went viral, here is a Vietnamese primary school puzzle that made the frontline in The Guardian. The question is: Fill the empty slots with all integers from 1 to 9 for the equality to hold. In other words, find a,b,c,d,e,f,g,h,i such that a+13xb:c+d+12xe–f-11+gxh:i-10=66. With presumably the operation

Executive summary Surprisingly good. And it’s not like my expectations were especially low. Structure There are 20 chapters. I mostly like the chapters and their order. Hadley breaks the 20 chapters into 4 parts. He’s wrong. Figure 1 illustrates the correct way to formulate parts. Figure 1: Chapters and Parts of Advanced R. Introductory R There The post Review of...

More on Likelihood Ratio Test, the following problem is originally from Casella and Berger (2001), exercise 8.12.ProblemFor samples of size $n=1,4,16,64,100$ from a normal population with mean $mu$ and known variance $sigma^2$, plot the power function of the following LRTs (Likelihood Ratio Tests). Take $alpha = .05$. $H_0:muleq 0$ versus $H_1:mu__0$$H_0:mu=0$ versus $H_1:muneq 0$SolutionThe LRT statistic is given by...

I haven’t posted for a while, so here are some news items: My new book, Parallel Computation for Data Science, will be out in June or July. I believe it will be useful to anyone doing computationally intensive work. After a few months being busy with the book and other things, I have returned to … Continue reading My...

Consider planning a clinicial trial where patients are randomized in permuted blocks of size four to either a 'control' or 'treatment' group. The outcome is measured on an 11-point ordinal scale (e.g., the numerical rating scale for pain). It may be reasonable to evaluate the results of this trial using a proportional odds cumulative logit

Just because I’m ignorant doesn’t mean I won’t try things. Feel free to correct any ignorance that follows. More than anything I would like to feature the new htmlwidget visNetwork. I thought the example from Minimum Spanning Trees in R a...

Huh… I didn’t realize just how similar rvest was to XML until I did a bit of digging. After my wonderful experience using dplyr and tidyr recently, I decided to revisit some of my old RUNNING code and see if it could use an upgrade by swapping out the XML dependency with rvest. Ultra Signup: Treasure Trove of Ultra Data If you’re...

e-mails with the latest R posts.

(You will not see this message again.)