Until recently I did not have a practical application in which to use streamgraphs. In fact, I still find the visualisation complex to understand, abstract and a bit too artistic. While I recognise that the strength of streamgraphs is the display of all the time seriesâ€™ values into one (possibly interactive) plot, the amount of data displayed is massive, with many streams and even more data points. Because of the amount of data displayed Continue reading “Streamgraphs in base::R [e.II]”

# Streamgraphs in base::R [e.I]

This is the first of a series of four post on producing a streamgraph in plain R code. Here I present a very simple R script plotting a streamgraph. In this post I made streamgraph in d3.js, but I wanted to be able to do the same in R, to not depend on a webpage, or without requiring additional libraries (e.g. the streamgraph htmlwidgtet is only a wrapper around d3, and does not work always smoothly).

Continue reading “Streamgraphs in base::R [e.I]”

# Clustering Pumps [mlw4]

This is the fourth and last assignment of Machine Learning for Data Analysis by Wesleyan University on Coursera. My assignment diverges quite a bit from the approach taken by the instructor since I wanted to have only three clusters to determine pumps functionality (functional, functional needs repair, and Continue reading “Clustering Pumps [mlw4]”

# Shrinking pumps? [mlw3]

This is the third assignment of the Machine Learning for Data Analysis by Wesleyan University on Coursera. I applied least absolute shrinkage and selection operator (LASSO) to the DrivenData data set pumpItUp. LASSO is a technique which does variable selection shrinking the ‘useless’ coefficients (i.e., variables) toward zero. Applying this method Continue reading “Shrinking pumps? [mlw3]”

# The forest and the pump! [mlw2]

The random forest algorithm is the topic of the second assignment of Machine Learning for Data Analysis by Wesleyan University on Coursera. This assignment extends the previous one because besides from using random forest instead of decision trees I included more variables than the previous assignment. In this analysis I included also Continue reading “The forest and the pump! [mlw2]”

# Pump it up with a decision tree [mlw1]

This post is about the first assignment of Machine Learning for Data Analysis by Wesleyan University on Coursera. In the past month I have tried to mine the dataset of the pumpItUp challenge on DrivenData. The challenge requires Continue reading “Pump it up with a decision tree [mlw1]”

# Making up for univariate [DAI IVb]

This post is an extension of this one, which was (supposed to be) the final post of the coursera course ‘data analysis and interpretation’. This current post extends or complements the previous one because in that assignment I forgot to include univariate graphs in my plot. Since I only had a bivariate graph, the other reviewers failed my assignment. I was quite disappointed by their reaction, but I understood their motives. If univariate graphs get points and the absence thereof does not, I was righteously failed. Therefore, in this post I try to fix my previous mistake including three univariate graphs. The conclusion one can gather from these graphs remains unchanged and one should Continue reading “Making up for univariate [DAI IVb]”