Symbol Meaning
γ γ code
γ Classification or clustering function: γ(d) is d’s class or cluster
Γ Supervised learning method in Chapters 13 and 14:Γ(D) is the classification function γ learned from training set D
λ Eigenvalue
~µ(.) Centroid of a class (in Rocchio classification) or a cluster (in K-means and centroid clustering)
Φ Training example
σ Singular value
Θ(·) A tight bound on the complexity of an algorithm
ω, ωk Cluster in clustering
Clustering or set of clusters
arg max


The value of x for which f reaches its maximum
arg minx f(x) The value of x for which f reaches its minimum
c, cj Class or category in classification
cft The collection frequency of term t (the total number of times the term appears in the document collection)
C Set {c1, . . . , cJ} of all classes
C A random variable that takes as values members of C
Back to top