There wasn’t as much happening here on the website in the last year as I planned, probably because there was a lot going on in life. I got married to my wonderful wife and I gave up my job as the head of health and infection reporting for the State Office for Environment, Health and
Cluster analysis is a useful method for finding structure in a mass of data. The main question in cluster analysis is: “Which objects are similar and which are not?” To answer this question, cluster analysis algorithms try to separate the data in clusters, where the clusters have a maximized similarity within the cluster and a
If you work in a scientific environment, you might work with LaTex. The question is how to get the table which we calculated with R to our LaTeX-paper without typing by hand. One answer (as usual, there is always more than one way) is to use the package “xtable”. To use this package, we have
Sometimes, especially if you use a variable as a container for a lot of calculation results, e.g., if there are correlations to calculate for a set of variables, you want to save the output to a file to print it out or use it otherwise. For tables that is not a problem. Here we can
The industrial age has radically changed our cities. Especially with the car as a means of mass transportation, the obvious coexistence of different areas of life has disintegrated and the structure of the city has literally melted away. How can we reclaim the city as a habitat? With concrete examples Wolfgang Christ discusses his approaches to urban/metropolitan areas. He developed, jointly with the Eco Institute in Freiburg, the concept of the “environmental railway station” (Umweltbahnhof) in Grünstadt northwest of Ludwigshafen,
For some cases it is helpful to store the data not in a file, but in a database. Databases have some advantages when it comes to a large amount of data. The most important factor is that for calculations, just the actual data that is needed for the calculation needs to be loaded in the random access memory (RAM). Another advantage is the possibility to run calculations (stored procedures) with some database engines which will speed up some complex calculations with large data sets, as well as the abolition of exporting the results for other programs e.g. to plot the data with a GIS System. A very good and easy way to implement the database connection in R is with RODBC.
After a couple months of hard work, I am proud to present the website in a new design as well as a new software system. As a result, I rearranged the pages and categorized them in a new way. As part of the revision, I switched this site completely to English. In the future, I