A Savitzky-Golay filter can be used as alternative to running mean or median filters. It tries to approximate a given signal using a sliding window approach and a low degree polynomial to model data within that window.
Sometimes we need to use special versions of R (e.g. the latest version of R is not available in the repositories of the machine we need to use). This post describes a simple way of compiling R from sources and using it in RStudio or on servers without X.
This example is a followup of hyperparameter tuning using the e1071 package in R. This time we're using the SVM implementation from the R caret package, a binary class classification problem and some extended features that come in handy for many classification problems. For an easy start with caret take a look at one of … Continue reading SVM classification example with performance measures using R caret
mctune In Machine Learning (ML) tasks finding good hyperparameters for machine learning models is critical (hyperparameter optimization). In R there exist some packages containing routines doing that for you using grid search (constructing and testing all possible parameters as a grid, e.g. in David Meyer's e1071 package). Besides the very good routines already contained in … Continue reading mctune: multicore hyperparameter tuning in R on the example of SVM car detection
Recently I did some Support Vector Machine (SVM) tests in R (statistical language with functional parts for rapid prototyping and data analysis -- somehow similar to Matlab, but open source ;)) for my current face recognition projects. To get my SVMs up and running in R, using image data as in- and output, I wrote a … Continue reading Image classification using SVMs in R