The standard deviation and range are both measures of the spread of a data set. Each number tells us in its own way how spaced out the data are, as they are both a measure of variation. The range relies on a very simple formula of subtracting the minimum data value from the maximum.
1 Locked Gold Chest, a chest found in the dungeon, which is opened with a Gold Key. 2  Pink Dungeon Chest, a chest that can be crafted. 3  Blue Dungeon Chest, a chest that can be crafted. 4  Green Dungeon Chest, a chest that can be crafted.
1 These belts vary in the types of secondary stat combos they have--the combos are set in advance and are not random.  Finally, Normal-mode dungeon gear has the chance to have a tertiary stat, and Heroic-mode dungeon gear has the chance to have a tertiary stat, Extra Socket, and/or be Warforged for a +6 item level boost.