In the discrimination problem the random variable

, known to take values in

, is estimated from the random vector

taking values in

. Ali that is known about the joint distribution of

is that which can be inferred from a sample

of size

drawn from that distribution. A discrimination rule is any procedure which determines a decision

for

from

and

. The rule is called

-local if the decision

depends only on

and the pairs

,for which

is one of the

closest to

from

. If

denotes the probability of error for a

-local rule given the sample, then estimates

of

, are determined for which

, where

and

are positive constants depending only on

,

, and

.