Responsive image

Meetup 2020-02-25 Minutes

For the first 2020 meetup we gathered in late February, just days before R’s official 20 year birthday. The great location this time was IBM Austria’s headoffice in the heart of Vienna and drinks and snacks were generously provided by the hosts. TALK ONE (Thomas, Thomas and Rudolf) The first presentation was held by IBM’s own (and ViennaR meetup member) Thomas [Strehl], Thomas [Weinrich] and Rudolf [Pailer]. The talk focused on how R based machine learning can be brought into an enterprise environment.

Meetup 2019-06-27 Minutes

R in corporate enivroments (finance depts.) Walter Djuric A short presentation, on the potential and real life uses of R (and RStudio) in a typical business (ie Accounting) department in a large Austrian financial institution. Common pitfalls (mostly linked to infrastructure problems eg firewalls, non-admin user-rights, AV software, etc) are discussed and a short overview of tactics for coping with these challenges is given (eg set up a local CRAN, package building so that R newbies can utilize it, enhanced .

Meetup 2019-05-14 Minutes

Easy peasy massive parallel computing in R (Mikkel) Mikkel a member and Co-Organizer of CopenhagenR paid a short visit to Vienna and before heading to Ennio Moricones (Vienna) concert he showed us around on the functionality of the ‘future’ and ‘furrr’ R packages. These provide a framework that make it possible to write code, that works seamlessly on a laptop or on a supercomputer. His R-talk showed us how.

Meetup 2019-02-12 Minutes

Self Service Data Preparation und Data Science Peter Jeitschko Peter presented Alteryx, a platform built for Business Analysts to master tasks like data management, data cleaning and modelling. The tool is windows only and will be ported to Linux soon. It can connect to multiple data sources and helps Business Analysts to deploy models in production. Finally, Peter also showed a Demo including data ingestion, an example of the Facebook Face API and some community features.




igraph Applications for Transportation Networks

Materials from Max Leodolters talk in May covering the igraph package. require(igraph) require(data.table) require(ggplot2) Centrality - What is it? Network Centrality gives you an idea of how important a vertex/node and edge/link in your network/graph \(N(V,E)\) respectively \(G(N,L)\) is. Examples: Closeness Betweenness Eigenvalue degree … Some formulas: Closeness Centrality \[ C^{node}(n) = \frac{1}{\sum_{m \in N \setminus \{n\}}d(n,m)} \] Betweenness centrality \[ B^{node}(n) = \sum_{m\neq o \in N\backslash \{n\} } \frac{\sigma_{mo}(n)}{\sigma_{mo}} \] Node-based Closeness for a link \[ \ddot{C}^{link}(l_{n,m}) = \frac{C^{node}(n) + C^{node}(m)}{2} \] Node-based Betweenness for a link \[ \ddot{B}^{link}(l_{n,m}) = \frac{B^{node}(n) + B^{node}(m)}{2} \] Link-based Betweenness for a link \[ B^{link}(l) = \sum_{n \neq m \in N } \frac{\sigma_{nm}(l)}{\sigma_{nm}} \] *\(\sigma\) is the number of traversing OD relations, and \(d(n,m)\) is the distance of the shortest route from \(n\) to \(m\) What to select, \(\ddot{B}^{link}(l_{n,m})\) or \(B^{link}(l)\)?

Meetup 06-2016 Minutes

SummerOfCode

SummerOfCode

The last meetup before the summer break concluded the igraph session with a talk by Rainer. Mario summed up his impressions from the R/Finance 2016 conference.


Meetup 05-2016 Minutes

IGraph

IGraph

This meetup extensively covered the igraph package with talks by Florian Sobieczky and Max Leodolter.