code: function diceCoefficient(value, alternative) {
    var val = String(value).toLowerCase()
    var alt = String(alternative).toLowerCase()
    var left = val.length === 1 ? [val] : bigrams(val)
    var right = alt.length === 1 ? [alt] : bigrams(alt)
    var leftLength = left.length
    var rightLength = right.length
    var index = -1
    var intersections = 0
    var leftPair
    var rightPair
    var offset
  
    while (++index < leftLength) {
      leftPair = left[index]
      offset = -1
  
      while (++offset < rightLength) {
        rightPair = right[offset]
  
        if (leftPair === rightPair) {
          intersections++
  
          /* Make sure this pair never matches again */
          right[offset] = ''
          break
        }
      }
    }
  
    return (2 * intersections) / (leftLength + rightLength)
  }
docs: Get the edit-distance according to Dice between two values.