public function decision($string)
    {
        // Do not call functions so that we'll compute only one time
        $dominantClass = $this->sentiment->categorise($string);

        switch ($dominantClass) {
            case 'neg':
                return self::NEGATIVE;

            case 'neu':
                return self::NEUTRAL;

            case 'pos':
                return self::POSITIVE;
        }
    }