Now that FG&DN is out on the streets, we’ve received a number of inquires on why we put in a rule to divide the gunnery modifiers by two. Most comments, and a few complaints, argue that this is overly complicated and unnecessary. To answer these comments, I’ll break up the answer into two parts. First, why we thought it was necessary and second, how we went about doing it. Most mathematical models tend to produce exaggerated results as you approach the extreme limits of their probability distribution curves. In other words, the model’s results at the low and high end of the curve tend to become distorted and out of scale with the rest of the model. This tendency is sometimes called “edge effect” and it is a real problem for combat models that depend on a turn-based approach to account for the passage of time. The vast majority of board and miniature games use turns to account for time, including the Admiralty Trilogy games, and players are limited in how far they can go or what they can do within that fixed period. During the play testing of FG&DN, we found that the Gunnery Standard concept suffered from significant edge effects when a large number of modifiers drove the probability of hit to very high or very low values. This was particularly true in the case of smaller combatants that could take advantage of high speeds and evasive steering. As the designers of the Admiralty Trilogy, we felt it was crucial to make it difficult to hit small ships at long range, but the model was making it too difficult to hit them at all! The opposite could be said of large, slow ships, which in certain circumstances, would always be hit. Neither of these outcomes was true to history, so a remedy had to be found to reduce the gunnery model’s edge effects. The problem we faced was that any solution had to remain faithful to the rest of the model, which did work well. The method we chose isolated the gunnery modifiers from the base chance to hit, that is, the base value would always remain the same while the total gunnery modifier value would be changed somehow. Through an iterative process, which included a lot of game testing, we decided to divide all modifiers by two before adding them to the base value. We did this because we found during our testing that it was much easier for the players to add modifiers based on 5% increments and then divide the total by two than to add a larger number of different modifier values (3%, 5%, 8%, 10% etc). There was also an unforeseen benefit in that a referee could actually speed up play by having players roll dice and only checking to see if a hit occurred if the die roll was close to the base probability of hit for that range band. For example, if a player is firing against a C or D size target at long range and he didn’t roll below a 25 on D100, a referee could simply move on to the next player without having to do the math to see if a hit occurred. I hope this brief explanation provides FG&DN players with an understanding of why and how we chose to address a problem we saw during game testing. BT Back to The Naval Sitrep #21 Table of Contents Back to Naval Sitrep List of Issues Back to MagWeb Master Magazine List © Copyright 2001 by Larry Bond and Clash of Arms. This article appears in MagWeb (Magazine Web) on the Internet World Wide Web. Other military history and related articles are available at http://www.magweb.com