library/Rediska/Key/SortedSet.php
public function incrementScore($value, $score)
    {
        return $this->_getRediskaOn()->incrementScoreInSortedSet($this->getName(), $value, $score);
    }
public function incrementScore($value, $score)
    {
        return $this->_getRediskaOn()->incrementScoreInSortedSet($this->getName(), $value, $score);
    }
Increment score of element

@param $value
@return integer