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setprior

SETPRIOR

Reset class prior probabilities of dataset

    A = SETPRIOR(A,PROB,LABLIST)

Input
 A Dataset
 PROB Prior probabilities to be set
 LABLIST Label list (optional)

Output
 A Updated dataset

Description

Resets the class prior probabilities of the dataset A to PROB. PROB should  be a vector of the length equal to the number of classes in A. In LABLIST,  the corresponding class labels may be supplied. LABLIST may have only  class names of the existing classes in A. Reset class names first by  SETLABLIST if necessary.

If LABLIST is not given, the order defined by the existing LABLIST for A (determined by [NLAB,LABLIST] = renumlab(LABELS)) is used.

PROB = 0 makes all C classes equally probable: 1/C PROB = [] is interpreted as using the existing class frequencies in A as  prior probabilities. Note that these prior probabilities change, if the  number of elements in A is changed, or its labeling.

See also

dataset, getprior, isempty,

PRTools contents

PRTools manual