code: function(attr) {
  			var newArr = [];
  
  			if (this.arr.length === undefined) {
  				// The wrapped array is a JSON object
  				for (var key in arr) {
  					newArr.push(this.arr[key][attr]);
  				}
  			} else {
  				// The wrapped array is an array
  				for (var i = 0, l = this.arr.length; i < l; i++) {
  					newArr.push(this.arr[i][attr]);
  				}
  			}
  
  			return stats(newArr);
  		}
docs: Replaces each element of the array with the attribute of that given element.  attr - The attribute to pluck.  Returns nothing.