Random Assignment Tables

Description

Random Assignment Tables or Random Allocation Tables (RATs) are provided in many BattleTech rulebooks and sourcebooks as a means for players to randomly generate plausible forces of multiple BattleMechs and/or vehicles for a given faction. In lieu with the game mechanics of the classic BattleTech (board game) they are invariably presented as either a 2d6 or a 1d6 table where each of the possible roll results (1 through 6 or 2 through 12) corresponds with a specific unit. It is possible for a specific unit to appear in several rows.

Inherent inaccuracy

RATs are typically of limited scope: They are usually provided for specific military units during specific campaigns and time frames. Conversely, they are a poor indicator for unit outside of their specific scope. They also suffer from the inherent limitations of the 2d6 table that only allows for eleven entries with only six tiers of statistical probability (the lowest being 2.77%, or 1 in 36, for the results "2" and "12" each). As such, they can only provide a very rough approximation for canonical force compositions of the units in question.

It has been clarified that RATs are not actually meant to provide an accurate picture of what forces a given faction has available. Rather, RATs, while rooted broadly in units would conceivably be available, are tailored to provide balanced gameplay over statistical accuracy.

(The Faction Assignment & Rarity Tables by Keith "Xotl" Hann are a fan project aiming to avoid this inherent accuracy, by using a much finer d1000 resolution and basing the tables on in-universe production and availability data, with no gameplay or balancing concerns whatsoever.)

Canonicity

Technically, RATs are fully canonical at least when published in a canonical product. However, their inherent inaccuracy as described above marks them as highly unreliable; they are a game rule more than a description of the BattleTech universe (see above). As a result, they are trumped by virtually any other canonical information regarding historical force compositions.