Intrusion-detection replication

A from-scratch replication of two papers on the UNSW-NB15 network-intrusion dataset: ten classifiers across seven feature scalings.

Sole author.

Select the features

Elastic-net regression chooses which of the flow features carry signal. The regularisation strength was picked on the error curve (optimal alpha 0.021).

See the classes

Interactive 3-D PCA, t-SNE and K-means clustering show how far the attack types overlap with normal traffic and with each other.

Measure the distances

Mahalanobis distances between class centroids, recomputed under each of the seven scalings, show how a scaler stretches or collapses the space between classes.

Benchmark everything against everything

Decision tree, Naive Bayes, logistic regression, k-nearest neighbours, SGD, SVM, MLP, XGBoost, bagging and a voting ensemble, each under no scaling, min-max, robust, standard, quantile, power and normaliser.

Profile the features

From the second paper: probability distributions, skewness, kurtosis, Pearson correlation and gain ratio per feature, then a complexity comparison of decision tree, Naive Bayes, logistic regression, a neural network and expectation maximisation.