Mode

Binomial distribution mode.

The mode for a binomial random variable is

m o d e left-parenthesis upper X right-parenthesis equals left floor left-parenthesis n plus 1 right-parenthesis p right floor

where n is the number of trials, p is the success probability, and ⌊x⌋ is the floor function.

Usage

var mode = require( '@stdlib/stats/base/dists/binomial/mode' );

mode( n, p )

Returns the mode of a binomial distribution with number of trials n and success probability p.

var v = mode( 20, 0.1 );
// returns 2

v = mode( 50, 0.5 );
// returns 25

If provided NaN as any argument, the function returns NaN.

var v = mode( NaN, 0.5 );
// returns NaN

v = mode( 20, NaN );
// returns NaN

If provided a number of trials n which is not a nonnegative integer, the function returns NaN.

var v = mode( 1.5, 0.5 );
// returns NaN

v = mode( -2.0, 0.5 );
// returns NaN

If provided a success probability p outside of [0,1], the function returns NaN.

var v = mode( 20, -1.0 );
// returns NaN

v = mode( 20, 1.5 );
// returns NaN

Examples

var randu = require( '@stdlib/random/base/randu' );
var round = require( '@stdlib/math/base/special/round' );
var mode = require( '@stdlib/stats/base/dists/binomial/mode' );

var v;
var i;
var n;
var p;

for ( i = 0; i < 10; i++ ) {
    n = round( randu() * 100.0 );
    p = randu();
    v = mode( n, p );
    console.log( 'n: %d, p: %d, mode(X;n,p): %d', n, p.toFixed( 4 ), v.toFixed( 4 ) );
}
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