[Old Pedant]

Is *THIS* what you are after:

<script type="text/javascript">

function findMode( arr )
{
    var counts = [ ];
    for ( var a = 0; a < arr.length; ++a )
    {
        var elem = "E" + arr[a];
        if ( counts[ elem ] == null ) 
        {
            counts[ elem ] = 1;
        } else {
            ++counts[ elem ];
        }
    }
    var half = 0.5 * arr.length;
    for ( var elem in counts )
    {
        // I don't think >= half works...what if the array is simply [1,2] ?? SO I used >
        if ( counts[elem] > half ) { return elem.substring(1); }
    }
    return "NONE";
}

var atest = [ 1, 37, 3, 2, 44, 1, 99, 1 ];
document.write( "Mode of [" + atest + "] is " + findMode(atest) + "<hr>" );

atest = [ 77, 101, 191, 91, 91, 191, 191, 191, 191 ];
document.write( "Mode of [" + atest + "] is " + findMode(atest) + "<hr>" );
</script>