References (trade)

References are arbitrary but structured designations used to identify where a particular resource — including raw materials, manufactured goods, or services — originates within the game world. A reference effectively marks the source location of a resource. The distance from a given location to a resource’s reference, along with the ease of transport, determines how strongly that reference influences local prices. Locations may be assigned one or several references for the same resource, depending on their commercial importance or production density. References are best assigned as whole numbers.

Markets seeded throughout the world receive resources from as many locations for which we choose to assign references. Thus, a specific place accumulates references for "iron" from potential dozens or hundres of other places — each adjusted as a fraction due to distance — and added together to be compared with gold to determine their price. Reference totals decay based on the number of transport-days they are from the source, plus one. If a market shares the same location as a reference, the distance is zero days; adding one makes the divisor 1, meaning the market receives the full value of that reference. If the reference were a transport-day from the market, the divisor would be "2" and the value of the reference at that market would equal one-half.

Typically, all the references within a given market's sphere of influence, called a "zone," are divided by 1 with respect to pricing that resource. Zones may be very tiny, where many closely located markets all compete for goods, or they may be huge, covering hundreds of thousands of square miles, where a single market accounts for all the goods in a vast empty realm. Thus resources are collected by markets in authority over their zone, before being exchanged with other markets. Each time a good passes through a market, +1 additional transport day is added to model transshipping, fees, tariffs or merely delays. This arbitrarily decays the availability of a given reference in areas where moving through numerous markets is common.

Market References

Markets, as well as goods, are identified by references. This designates the relative importance of a market with regards to the scale of larger commercial centres throughout the world. A small market, with 1 reference, adds the same additional transport day as any other market; overland, the chief importance of additional market references applies to availability of capital, rather than adjustments to references.

Geographical Distance

Transport days are defined by the use of a 20-mile hex map. Each overland hex counts as one "day" — and as hexes are defined additionally by an elevation, the number of days is further adjusted by +1 day per 400 foot difference between elevations, whether ascending or descending. Thus two places that were one hex apart, with the first at sea level (0 elevation) and the other at 40 feet above sea level, would count as 1.1 transport days apart.

Rivers

When moving goods downstream, the difference in elevation is divided by "133", such that the distance between hexes declines due to the ease of travel upon a stream. If the benefit is higher than -0.33, however, the river flow is considered too fast, so that -0.33 is the highest benefit that can be achieved when shipping goods in this manner.

When hauling goods upstream, the adjustment is reversed, so that the difference is divided by "133x-1", thus decreasing the ease of travel by the same amount as it would have otherwise been improved. When moving upstream, there's no limit as to how much detriment is suffered due to the river's speed of flow.

This retains compatibility with road travel capacity. Goods that are transshipped from roads to streams where no market exists suffer no additional penalty to transport-days; however, most transshipment points do have a market attached, so that the usual +1 transport day is added as goods are moved from overland to river transport.

Sea Travel

Travel over water, including across lakes large enough to cover more than one hex, counts each hex of journey as ⅓-day, or three hexes per day of travel. This reflects the relative speed and efficiency of waterborne movement over long distances. By applying this rule to both seas and large lakes, it provides consistency in that navigable inland waters did function as major trade routes.

Market ports, however, are limited by their reference number with regards to the distance from which they can import goods. A port with 1 reference can only import from other ports that are within 10 hexes (200 miles), and of course from overland trade. Such a port may, however, still export to markets much farther away, whose reach does include the smaller commercial port.

For example, the port of Derna in the northern province of Marmarica in Libya has 2 market references, so it can import goods from as far away as 20 hexes, or 400 miles. This allows it to import from Athens (or rather, it's port of Aslan Liman), which is 18 hexes away. But it cannot import from Genoa, which is much farther. Genoa, however, has 18 market references. It can easily therefore import from Derna, so that Genoese ships in its harbour are certain to be loading goods, rather than unloading. Yet because Athens imports from much further away (it has 7 market references), this allows Derna to receive many goods from that port second hand, as well as Bengazi (4 market references), as both these ports have access to a much wider sample of trade goods.

Yet it means that goods in Derna are marginally more expensive, as they must pass through other ports, than goods would be in nearby Benghazi, 10 hexes away.

Reference Types

What references we choose to keep track of reflects the degree of grittiness for the world we've designed. To express the cost and distribution of sustenance, we could simply ascribe references for "food", adding as many as are needed to account for all the cereals, fruits, vegetables, meat and beverages, without needing to be particular. Alternately, we could deepen the system by defining references for "cereals" and the other things just named. We can go a step further and separate beverages into brewing, distilling, wine, mead and so on. Of course, we can go further, specifying the origins of varieties of each. We might offer one reference in one location for a given wine, "Sack," thus indicating that all Sack in the world comes from this one place... with both a growing expense for the wine as we travel farther and farther away, until we reach an inevitable distance where the number of references available (the demand) has dwindled to the point where there is no demand. And no Sack to be had at any cost. Reasonably, at such a point, we should assume most of the residents have never heard of Sack.

By scattering hundreds of references for a common good, say "hides," we assure that no place within the world is ever far from at least one or two such references. The price may wax and wane as we move towards places that have greater access to many, rather than merely some, source references, but the price for that particular good never becomes untenable. Therefore, we have both the choice of defining "how many" references we choose to assign vs. "how scattered."

References may be grouped into general categories, each of which can easily have dozens of more specific varieties: agricultural products, livestock, seafood, foodstuffs (made from produce and animals), cloths, woods, stone, building materials, metals and alchemy. A lightly detailed system could thus specify 80 or so reference types. A more robust system could easily have more than 800. An example of a region's assigned references in this wiki can be seen here.

See also,
Locating References
Sea Routes
Trade System