math.random() > .5 and 1 or 0 code example
Example 1: javascript random number between 0 and 10
Math.floor(Math.random() * 10);
Example 2: javascript random number 1 or -1
//an equation that returns either 1 or -1
var number = ((Math.floor(Math.random() * 2) - 2) * 2) + 1