I know price guide values are often "off" from true market values. How are they with regards to ranking the order of value though? Lets take the most popular coin guide (the Red Book) as an example. Even though the prices for a given series might be inaccurate if you were to rank those coins based off those prices are they fairly accurate in their order?
I think that price guides that have been issued for a long time, like "The Red Book" are pretty decent in that regard. The relative values placed on coins there are farily accurate because those rankings have been in place for a long time. For example the 1877 and 1909-S Indian Head cents have been at the top of the list, in the circulated grades, since I started as a collector in the early 1960s. Mint State coins can be a different story because very high grade pieces can bring very strong prices because of "condition rarity." The place were "The Red Book" falls down is where it places values on some of the rare varieties that are on its lists. I collect early half dimes. If you look at "The Red Book" you would think that the 1797, 13 star and the 1803 Small date half dimes are worth about the same as the other coins listed for those years. They aren't. When they are sold at auction, they birng much higher prices, if they are decent coins, because they are much rarer than the price guide indicates. There are perhaps 50 known examples of the 1797, 13 star half dime and maybe less than 20 known examples of the 1803 Small Date half dime. You would never be able to guess that from "The Red Book" listings.
