jeudi, septembre 27, 2007

Scoring function

This part discusses scoring issues. Please refer to this for info.


Definition:

  • instances = data objects observed and analysed (sometimes referred to as objects, data points...)

  • variables= characteristics measured (for continuous) or observed (for categorical) for each instance


Notation:

  • n data objects (sample size)

  • X generic input variables. When it is a vector, its component variable j is expressed with subscript: Xj

  • x denotes some observed instance, and when we have p-variables, we denote x1 .. xp as the the real-valued for the 1.. p variables measured on the particular object or instance.

  • xk(i) correspond to the measure for variable Xk of the i-th data objects, where i has 1 .. N.

  • x (in bold) correspond to the vector of n observation of a single variable x.

  • X (capital in bold) correspond to the matrix N x p, containing N input p-vector xp(1..N).