##  [Covariance Kernel](/covariance-kernel) 

  ##  [Covariance Kernel](https://natural.quantumdictionary.io/covariance-kernel-0) 

  

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**Natural & Formal Sciences Dictionary**

 







 

 

 

 



 

 

 

 

Definition

A symmetric positive semidefinite function k(x,y) on an index set that represents the covariance function of a second‑order stochastic process or the Mercer kernel of a positive integral operator; for any finite collection {x_i} the matrix [k(x_i,x_j)] is positive semidefinite.