- Lattices and other algebras with two operations.
- Concept lattices and association rules.
- Rough sets and fuzzy sets.
- Metrics, ultrametrics, dissimilarities, and similarities.
- Metric and topological spaces.
- Dimensionality and the curse of dimensionality.
- Eigenvalues, eigenvectors, PCA, SVD.
- Mathematical foundations of clustering algorithms.
- Clustering quality assessment.
- Entropy, Kullback–Leibler divergence, mutual information, coding limits, and code sets.
- Variable-length codes and statistical coding.
- Fourier transform.
- Wavelet transform and convolution.