Mode
The mode for a beta random variable is
for α > 1 and β > 1. For other values of first shape parameter α and second shape parameter β, the mode is not defined.
Usage
var mode = require( '@stdlib/stats/base/dists/beta/mode' );
mode( alpha, beta )
Returns the mode of a beta distribution with parameters alpha (first shape parameter) and beta (second shape parameter).
var v = mode( 2.5, 1.5 );
// returns 0.75
v = mode( 4.0, 12.0 );
// returns ~0.214
v = mode( 8.0, 2.0 );
// returns 0.875
If provided NaN as any argument, the function returns NaN.
var v = mode( NaN, 2.0 );
// returns NaN
v = mode( 2.0, NaN );
// returns NaN
If provided alpha <= 1, the function returns NaN.
var v = mode( 0.5, 1.0 );
// returns NaN
v = mode( -1.0, 1.0 );
// returns NaN
If provided beta <= 1, the function returns NaN.
var v = mode( 1.0, 0.5 );
// returns NaN
v = mode( 1.0, -1.0 );
// returns NaN
Examples
var randu = require( '@stdlib/random/base/randu' );
var EPS = require( '@stdlib/constants/float64/eps' );
var mode = require( '@stdlib/stats/base/dists/beta/mode' );
var alpha;
var beta;
var v;
var i;
for ( i = 0; i < 10; i++ ) {
alpha = ( randu()*10.0 ) + 1.0 + EPS;
beta = ( randu()*10.0 ) + 1.0 + EPS;
v = mode( alpha, beta );
console.log( 'α: %d, β: %d, mode(X;α,β): %d', alpha.toFixed( 4 ), beta.toFixed( 4 ), v.toFixed( 4 ) );
}