What is appearance ratio?

In the editor, there is a column called "appearance ratio" for each type of resource. There is a positve value for each strategic resource while others are "0".

What does the value mean?
(eg horse's appearance ratio is 160. So how frequent will it occur indeed?)

PS: I have read the "editor help" but I still don't understand.

Generate a couple random maps in civedit and observe how many of each resource is usually generated; thats the best way to figure things out, since that way you can play with the numbers (IE set one to minimum and one to maximum value) and see how much they are affected.

Generate a couple random maps in civedit and observe how many of each resource is usually generated; thats the best way to figure things out, since that way you can play with the numbers (IE set one to minimum and one to maximum value) and see how much they are affected.
Thanks for your suggestion.

If anyone knows any formula which can translate the value into some meaningful figure (eg the actual number of resources on a particular map), it would be great.

No... What I can tell is that 160 means about 2 resources per civ...

No... What I can tell is that 160 means about 2 resources per civ...
And it seems it is dependent on the player size too. To make 160 = 2 resources per player, it specifies it has to be 8-player game in the "help" file.

So my fist instinct about the forumla might be: "appearance ratio / 10 / no. of player"
160 / 10 / 8 = 2 resources per player
However if the forumla is true, then the more the player, the fewer the resource we can. The result seems strange.

One of the reasons I hate to play randomly generated maps is the scarcity of relatively common but crucial resources like iron, saltpeter. I guess I could look at editing the Civ.biq and fix that right?

When the value is zero, it follows a set formula for bonus resources, which are by default pretty plentiful (not sure how plentiful, but probably 3 or more per civ).

But is it the higher the value, the more frequent the resource will be on the map?

Yes, on appearance ratio, higher numbers mean higher frequency. Look at the value for Uranium (100), which is the most rare of strategic resources, and compare it with Iron and Horses (160), the most plentiful. There isn't much difference. I've used 180 as a value for Iron, and it made it easier to acquire, but almost too easy. If you want only one or two sources of a resource to appear, you may only need a value of 20 on an 8-player map.

For disappearance probability, the lower numbers indicate a greater likelihood of the resource disappearing once it is connected via a road. Iron, the hardest to exhaust, has a value of 800, while Uranium, the easiest to exhaust, has a value of 100. If you want something to never disappear, give it a zero (like Horses). A value of 10 might have things popping in and out of existence rather quickly. Anytime a resource disappears, it reappears somewhere else on the map. I've used this setting for some resources that I want to be very rare and easy to lose. A great leader resource, for example, required for building the wonders that have a person's name on them, like Copernicus Observatory. This "Innovator" resource in my mod has an appearance ratio of 10 and a disappearance probability of 10.

And it seems it is dependent on the player size too. To make 160 = 2 resources per player, it specifies it has to be 8-player game in the "help" file.

So my fist instinct about the forumla might be: "appearance ratio / 10 / no. of player"
160 / 10 / 8 = 2 resources per player
However if the forumla is true, then the more the player, the fewer the resource we can. The result seems strange.

You're mistaken, the eight player reference is only an example. The number of resources is dependant on the total number of civs in a game. So a 16 player game will have roughly double the amount of an 8 player game. And I believe that number is more like 125 for one resource per civ in Vanilla/PTW, and 133 in Conquests.

This thread Embryodead made right after C3C came out about resource appearance ratios might clarify this ---> Distribution of resources in C3C is TOTALLY different (details) (http://forums.civfanatics.com/showthread.php?t=69502)