number of failures until experiment is stopped
success probability
expected value
var v = mean( 100, 0.2 );
// returns 400.0
var v = mean( 20, 0.5 );
// returns 20.0
var v = mean( 10.3, 0.8 );
// returns ~2.575
var v = mean( -2, 0.5 );
// returns NaN
var v = mean( 20, 1.1 );
// returns NaN
var v = mean( 20, NaN );
// returns NaN
var v = mean( NaN, 0.5 );
// returns NaN
Returns the expected value of a negative binomial distribution.
Notes
r
which is not a positive number, the function returnsNaN
.p < 0
orp > 1
, the function returnsNaN
.