Blog Archives

Speedmining the Cubing Community with dbplyr

Speedmining the Cubing Community with dbplyr

Abstract: We use the RMariaDB and dbplyr packages to analyze the results database of the World Cubing Association. In particular we are interested in finding unofficial world records of fastest 3x3x3 solves, countries with large proportion of female cubers as well as acceptable solving times before entering a WCA competition. This work is licensed under a Creative Commons Attribution-ShareAlike 4.0...

Read more »

A Shiny app for your perfect circle

February 14, 2019
By
A Shiny app for your perfect circle

Abstract: The perfect circle is a shiny app providing a user friendly interface to the algorithm described in the previous blog post Judging Freehand Circle Drawing Competitions. The app allows one to score freehand circles directly from the mobile by uploading photos of them them to a shiny server. An R package "perfectcircle" contains the scoring API as well as...

Read more »

Purr yourself into a math genius

January 3, 2019
By
Purr yourself into a math genius

Abstract: We use the purrr package to solve a popular math puzzle via a combinatorial functional programming approach. A small shiny app is provided to allow the user to solve their own variations of the puzzle. This work is licensed under a Creative Commons Attribution-ShareAlike 4.0 International License. The markdown+Rknitr source code of this blog is available under a GNU...

Read more »

Is the answer to everything Gaussian?

October 28, 2018
By
Is the answer to everything Gaussian?

Abstract: As an applied statistician you get in touch with many challenging problems in need of a statistical solution. Often, your client/colleague already has a working solution and just wants to clarify a small statistical detail with you. Equally o...

Read more »

Judging Freehand Circle Drawing Competitions

July 30, 2018
By
Judging Freehand Circle Drawing Competitions

Abstract: In 2007 Alexander Overwijk went viral with his 'Perfect Circle' video. The same year a World Freehand Circle Drawing Championship was organized, which he won. In this post we show how a mobile camera, R and the imager package can be used to develop an image analysis based method to judge future instances of the championship. This work is...

Read more »

Amazon’s Hanging Cable Problem (Golden Gate Edition)

July 22, 2018
By
Amazon’s Hanging Cable Problem (Golden Gate Edition)

Abstract: In this post we use R's capabilities to solve nonlinear equation systems in order to answer an extension of the hanging cable problem to suspension bridges. We then use R and ggplot to overlay the solution to an image of the Golden Gate Bridge in order to bring together theory and practice. This work is licensed under a Creative...

Read more »

World Income, Inequality and Murder

World Income, Inequality and Murder

Abstract: We follow up on last weeks post on using Gapminder data to study the world's income distribution. In order to assess the inequality of the distribution we compute the Gini coefficient for the world's income distribution by Monte Carlo approximation and visualize the result as a time series. Furthermore, we animate the association between Gini coefficient and homicide rate...

Read more »

Factfulness: Building Gapminder Income Mountains

Factfulness: Building Gapminder Income Mountains

Abstract: We work out the math behind the so called income mountain plots used in the book "Factfulness" by Hans Rosling and use these insight to generate such plots using tidyverse code. The trip includes a mixture of log-normals, the density transformation theorem, histogram vs. density and then skipping all those details again to make nice moving mountain plots. This...

Read more »

Retracing Prenatal Testing Algorithms

June 13, 2018
By
Retracing Prenatal Testing Algorithms

Abstract A good understanding of the statistical procedure used to calculate trisomy 21 (Down syndrome) risk in combined first trimester screening is a precondition for taking an informed decision on how to proceed with the screening results. For this purpose we implement the Fetal Medicine Foundation (FMF) Germany procedure described in Merz et al. (2016). To allow soon-to-become-parents an insight...

Read more »

Safe Disposal of Unexploded WWII Bombs

Safe Disposal of Unexploded WWII Bombs

Abstract Unexploded WWII bombs are ticking threats despite being dropped more than 70 years ago. In this post we explain how statistical methods are used to plan the search and disposal of unexploded WWII bombs. In particular we consider and exemplify the non-parametric nearest neighbour distance (NND) method implemented in the R package highriskzone. The method analyses the spatial pattern...

Read more »

Search R-bloggers

Sponsors

Never miss an update!
Subscribe to R-bloggers to receive
e-mails with the latest R posts.
(You will not see this message again.)

Click here to close (This popup will not appear again)