Thoughts on GURPS economics?

[aramis]

The moment you cross 27 jumps per year, you ha me violated canonical trade Praxis...I myself have pointed out the shorter cycles makes the hg ships much more profitable.

You're now arguing from a point of bad faith, by ignoring when convenient, conditions which are a default you've chided me on not using in other discussions. Can't have it both ways, Hans...

Canon says normal operations are 2 weeks per jump. Canon also establishes that the normative cycle is 5days on world, and 6-8 in jump, plus 1day of transit time. GT doesn't change that assumption.

 

[rancke]

The moment you cross 27 jumps per year, you ha me violated canonical trade Praxis...I myself have pointed out the shorter cycles makes the hg ships much more profitable.

You're now arguing from a point of bad faith, by ignoring when convenient, conditions which are a default you've chided me on not using in other discussions. Can't have it both ways, Hans...

It's not ignoring when convenient, Wil, it's ignoring when canon makes absolutely no sense. I feel that my faith is perfectly good.

Canon says normal operations are 2 weeks per jump. Canon also establishes that the normative cycle is 5days on world, and 6-8 in jump, plus 1 day of transit time. GT doesn't change that assumption.

But canon does not explain WHY normal operations for regular shipping companies are 2 weeks per jump. There is no reason for that. The reason given for why tramp ships spend an average of 5 days in port does not apply to regular shipping. This is a blatantly broken rule.

Come to that, canon only says anything about normal operations for single jump trading (One world to a neighboring world). It says not a single word about long distance transport. What it does say is that a jump averages 168 hours and that a jump drive should rest for, I think it is 16 hours, before being used to jump again. If a ship only needs to refuel and the traffic flow is high enough to support a near space fuel station, refuelling should be doable in those 16 hours. That would make for an average time per jump of 7.67 days, allowing up to 45 jumps per year[*]. I'm being positively conservative in sticking to 35 jumps per year.

[*] That doesn't account for the stops at each end of the route, so probably a full 45 jumps per year are not feasible.​

Hans

 

[mike wightman]

This actually makes a lot of sense. The trade rules are for a free trader scraping together an existence.

A shipping company that operates in a subsector could make a lot more profit in a couple of ways:

1. employ someone on each planet to have passengers and cargos ready ahead of time for the ship - thus allowing for more than 25 jumps per year.

2. build your own fuel purification plant - buy unrefined fuel and make your own refined.

Canon doesn't give rules for either but they are a no brainer.

 

[rancke]

To please Wil I'll make my assumptions compatible with CT canon. That is to say using canon for anything for which canon exists, however ludicrous, and making up stuff that doesn't contradict known canon (however ludicrous) for anything for which no canon exists.

Here we go, then: The average long distance trade route is three jumps long. A ship will leave its homeworld and jump to the first system on the route, where it will arrive an average of 7 days later. Assuming (as I do) that this is on a major trade route, it will arrive close to a space station with refuelling capability. Moving to the station, being refuelled, and moving away from the station takes 24 hours on the average, for an average of 8 days. It jumps to the next system along the route where the process is repeated. It then jumps to its ultimate destination where it moves down to the mainworld, unloads its cargo, loads another cargo, and then sits around twiddling its metaphorical thumbs until the canonical 5 days for a visit to a world are up before it heads back. Sum total, 30 days spent on three jumps, or 35 jumps per year.

Does that satisfy you, Wil?


Hans

PS. Yes, I know. 35 jumps per year leaves the poor ship in an intermediary system when annual maintenance is due. There are various ways to deal with that, all of which adds a little bit to the jump average. The simplest is to perform annual maintenance every 33 jumps. Or we could shave a few hours off the average for each jump, making the 3 jumps take 29 days 4 hours, allowing 36 jumps per year.

 

[Carlobrand]

It's not ignoring when convenient, Wil, it's ignoring when canon makes absolutely no sense.

You're absolutely right. And, after due consideration, I've decided that GURPS makes absolutely no sense. With all due respect to the professional economist, I've never been one to be too deeply swayed by appeals to authority. The authority needs to be able to persuade me - and so far, I haven't seen anything like an effective argument for basing trade on a logarythmic range scale when the costs of transport are linear. It struck me as arbitrary and unrelated to any of the ground-level game mechanics, more intent on achieving a desired end than on achieving an effective large-scale simulation of the game mechanics. And, again with due respect to his professional skills, I don't think he has much experience of star-spanning economies involving transportation times of months and years.

If I understand this correctly, the professional economist's rules say that the trade volume is decided not just by how much the smaller economy wants, but also by how much the larger economy can push out: when a very small economy's trading with a very larg economy, you can essentially consider that ALL of the smaller economy's GDP consists of that trade. Well, that just ain't the way it works - If you got it and they don't want it, they don't buy it. And, there is ALWAYS an internal economy going on. Even in the case of a captive world, you've got the people producing food (even if it's just Soylent), the people distributing food, the people maintaining and repairing equipment, the medical community, and so on, and so on. At it's most extreme, no more than about half the economy's going to be trade with external partners - and currently the trend ranges mostly between 10 to 30 percent, with only folk like the Saudis and the UAE getting far over that.

The professional economist also seems to be saying there's no effective difference between a jump-3 trade route and a jump-5 trade route - same modifiers. Anyone here ready to buy that in the CT universe?

Maybe this thing works for GURPS - I don't know enough about how their ships operate, how much they cost, fuel consumption and so forth. However, it doesn't seem to be working for CT. It's giving me worlds with nothing more than barren bedrock landing fields playing host to daily visits from cargo ships - many seeing a half dozen daily including 4000-tonners, a couple seeing 10 or more a day (Zila, Plaven). It's giving me worlds with no more than a village on the whole planet serving as major transshipment points for goods crossing 4 or 5 parsecs to reach markets that could more easily and more cheaply be served by the planet "next door".

I'me tempted to design my own system - take the GURPS bit (if I can ever get the book), set limiters so it's based more on demand than supply, and make that range modifier linear - or perhaps come up with some numbers that more closely aapproximate what CT range costs are like. For the moment, my guesstimates are going to be based primarily on GDP and starport, maybe with a modifier for particular needs - and I can assure you Drolraw is not going to be needing those warehouses.

 

[rancke]

You're absolutely right. And, after due consideration, I've decided that GURPS makes absolutely no sense.

Your priviledge.

With all due respect to the professional economist, I've never been one to be too deeply swayed by appeals to authority. The authority needs to be able to persuade me - and so far, I haven't seen anything like an effective argument for basing trade on a logarithmic range scale when the costs of transport are linear. It struck me as arbitrary and unrelated to any of the ground-level game mechanics, more intent on achieving a desired end than on achieving an effective large-scale simulation of the game mechanics. And, again with due respect to his professional skills, I don't think he has much experience of star-spanning economies involving transportation times of months and years.

No, he was probably limited to knowledge about trade flows on Earth, where the gravity model of trade appears to have some empirical evidence to support it. But I'm sure your instincts are better able to discern the truth.

If I understand this correctly, the professional economist's rules say that the trade volume is decided not just by how much the smaller economy wants, but also by how much the larger economy can push out: when a very small economy's trading with a very larg economy, you can essentially consider that ALL of the smaller economy's GDP consists of that trade.

Is that what the rules say? I hadn't realized. Well, I'm sure you know better than Jim McLean.

Well, that just ain't the way it works - If you got it and they don't want it, they don't buy it. And, there is ALWAYS an internal economy going on. Even in the case of a captive world, you've got the people producing food (even if it's just Soylent), the people distributing food, the people maintaining and repairing equipment, the medical community, and so on, and so on. At it's most extreme, no more than about half the economy's going to be trade with external partners - and currently the trend ranges mostly between 10 to 30 percent, with only folk like the Saudis and the UAE getting far over that.

If it doesn't work that way then maybe the rules don't actually say what you think they say.

The professional economist also seems to be saying there's no effective difference between a jump-3 trade route and a jump-5 trade route - same modifiers. Anyone here ready to buy that in the CT universe?

I thought he was saying that his rules were a crude model more suited for easy game play rather than an exact and detailed model suitable for detailed exonomic analysis.

Maybe this thing works for GURPS - I don't know enough about how their ships operate, how much they cost, fuel consumption and so forth. However, it doesn't seem to be working for CT. It's giving me worlds with nothing more than barren bedrock landing fields playing host to daily visits from cargo ships - many seeing a half dozen daily including 4000-tonners, a couple seeing 10 or more a day (Zila, Plaven).

How do you manage to get such figures? At a rough guesstimate I get a trade volume of around 10,000-50,000 T per year for Zila, which doesn't seem out of line for a population of 70 million people. I grant you that the hundreds of dT per year that Plaven gets seems high for a population of under 10,000 people. But then, FT specifically states that the model tends to break down for extreme values (p. 15). The rule it presents to refine this (BTN can never exceed the smaller WTN plus 5) is insufficient to ameliorate the problem for low-population worlds. I don't throw away the tool because it doesn't work perfectly in all cases, though. I merely apply it with a bit of care and reduce the trade flow for low-population worlds.

It's giving me worlds with no more than a village on the whole planet serving as major transshipment points for goods crossing 4 or 5 parsecs to reach markets that could more easily and more cheaply be served by the planet "next door".

How does it do that?


Hans

 

[Carlobrand]

...No, he was probably limited to knowledge about trade flows on Earth, where the gravity model of trade appears to have some empirical evidence to support it. But I'm sure your instincts are better able to discern the truth.

Better? No. But certainly as good when dealing with something entirely outside his field of expertise - unless you're about to propose that terrestrial trade economics fueled by oceangoing ships, planes, trains and trucks and such are a good basis for judging interstellar economics

Is that what the rules say? I hadn't realized. Well, I'm sure you know better than Jim McLean.

1. Who is Jim McLean?
2. As I've repeatedly stated, I don't own the books and am obliged to judge by second-hand references, including the posts here. As you clearly own and understand those rules, you would probably be more persuasive - and more helpful - by explaining where I'm wrong than by playing at gentle sarcasm games.

If it doesn't work that way then maybe the rules don't actually say what you think they say.

See #2 above. Aramis has been good enough to lay out the rules as he understands them, in some detail. You have been ... adamant, but somewhat less helpful. If obliged to choose between hard data and clever wordplay, I think I'll stick with the data.

I thought he was saying that his rules were a crude model more suited for easy game play rather than an exact and detailed model suitable for detailed exonomic analysis.

Was he? I wouldn't know. I have only the fact that he offered the same DM for a 3, 4, or 5 parsec trade route. If he is indeed saying his rules are a crude model, then perhaps he won't mind my adjusting them somewhat to more effectively reflect this game's play.

How do you manage to get such figures? At a rough guesstimate I get a trade volume of around 10,000-50,000 T per year for Zila, which doesn't seem out of line for a population of 70 million people.

I read the UPP. Handy thing, you should try it. Zila, for example has a Class E starport, a "Frontier installation. Essentially a marked spot of bedrock with no fuel, facilities, or bases present." (CT Book 3, etc.) The Spinward Marches Sector trade map based on GURPS rules ...

http://images1.wikia.nocookie.net/_...eller/images/2/2a/Spinward_Marches_Sector.pdf

...tells us that this bare spot of bedrock serves no less than three feeder routes, averaging between twelve and twenty four "larger freighters" and "an equal number of smaller liners and free traders," serving an average 30,000 dTons of cargo weekly, with 6 to 12 ships every day offloading and then taking on 4000+ dTons of cargo at that "marked spot of bedrock with no fuel, facilities, or bases present" and then trying to scrounge fuel from the local seas. At least, so says the accompanying trade map key:

http://traveller.wikia.com/wiki/Trade_map_key

I grant you that the hundreds of dT per year that Plaven gets seems high for a population of under 10,000 people. But then, FT specifically states that the model tends to break down for extreme values (p. 15). The rule it presents to refine this (BTN can never exceed the smaller WTN plus 5) is insufficient to ameliorate the problem for low-population worlds. I don't throw away the tool because it doesn't work perfectly in all cases, though. I merely apply it with a bit of care and reduce the trade flow for low-population worlds.

Well, it breaks down for Class E starports, too. There being a whole lot of class E starports (93) and quite a few low pop worlds (150 with pop value 4 or lower, out of 439 March worlds), I think it becomes fair to question the value of a tool that gets it wrong for 1/3 or more of the cases it's applied to.

How does it do that?

Mercury (B658663-8), Strouden (A745988-D), and Lunion (A995984-D) each run "main" routes through Sharrip to each other. One has to presume Sharrip is only a waypoint; there are only 50 people on the world, the cargo is clearly not stopping there. The route from one through Sharrip to the other is 4 to 5 parsecs in two jumps. However, each of the three world also runs trade routes to good-sized neighbors within 1 to 2 parsecs of them. Could well be one of those "breakdowns" but, again, what good is the tool if it needs correction a third of the time or more? When it breaks down that often, the tool itself is in need of some serious tweaking.

Once more, all I have to go on is these maps. If you're about to tell me they do NOT reflect GURPS trade rules, or that they've made some major mistake, then I will jump with joy and forget I ever saw them. Otherwise, this doesn't exactly make those rules look good.

 

[aramis]

Canon also says that it takes 4 days to deliver stuff from seller to the holds, Hans. (Bk7, p. 42) And it strongly implies 5 days to get people aboard from calling for pax.

And, since canon CT says both Bk2 and Bk5 ships coexist, and Bk2 2000 and 3000Td ships can carry for under KCr1/Td/Pc at one jump per 2 week...

The costs and operation rates are canonical - they're reinforced in Bk7, MT, and TNE. And T5.

And, if we add in the canonical but usually ignored travel times for travel from the stellar 100 diameter limits, a significant number of worlds are well more than a week from the jump point... I've not looked at the specifics - because I pointedly ignore the 100D limit of stars in my play - it's a hassle... tho', in my last campaign, I used them because Marc niftily provided handy tables for those limits in T5... Several of my mainworlds were 3-6 days in, and I used mass shadow but not target point masking, so you could come out anywhere outside the sphere, including the far side of the star.

Simply put, even 14 days per cycle is pushing it unless you're maintaining system tugs and a jump-point "station" at all the deep wells... a place to stage cargo so it's ready for immediate load/unload near the jump point - but you need enough so that all the ships arriving are outside each other's 36 hour windows... and it's easiest if it's just pod-swap - but that's outside the realm of CT design systems.

But system shipping has costs, too....

 

[rancke]

Seems like I have to back down on some of my assertations. Unpleasant prospect, but it has to be done.

I've only used FT's trade rules to map out a couple of small regions with adequately sized populations. Not that there weren't low-population worlds among them, but I never even considered that they would have any significant trade, so I've ignored them. But after looking into the matter last night, I'm forced to admit that the system seems to produce overly large trade volumes for low-population worlds.

I've no such reservations about high-population worlds in general or a few thousand T per year reaching Mora from Terra. But distances much higher than from one end of the Imperium to the other (and less than that for routes that leaves the Imperium) does bother me after thinking it over.

Better? No. But certainly as good when dealing with something entirely outside his field of expertise - unless you're about to propose that terrestrial trade economics fueled by oceangoing ships, planes, trains and trucks and such are a good basis for judging interstellar economics

But it isn't entirely outside his field of expertise. However good or bad a basis terrestrial trade is for establishing interstellar economics[*] (How good a basis it is depends on how close the analogy is), it seems to me that it probably is better than no knowledge at all.

[*] Establishing, not judging. The man was creating rules for a fictive subject. That means that if what he says isn't demonstrably wrong, it's right.​

1. Who is Jim McLean?

The economist who was one of the three authors of FT.

2. As I've repeatedly stated, I don't own the books and am obliged to judge by second-hand references, including the posts here. As you clearly own and understand those rules, you would probably be more persuasive - and more helpful - by explaining where I'm wrong than by playing at gentle sarcasm games.

I'm not able to show that you're wrong. I was saying that unless you could prove that a rule is wrong, the default assumption is that it is right.

As an example, I reject the rule that require regular ships to spend five days in port waiting for the suppliers to deliver the goods to the ship because I know for a fact that it's possible for a regular shipping line to have a factor and warehousing on a world and to buy the goods beforehand, have them delivered to the warehouse, and have them ready to load as soon as the ship has landed and unloaded its previous cargo.

Was he? I wouldn't know. I have only the fact that he offered the same DM for a 3, 4, or 5 parsec trade route.

I don't even think that two different sets of worlds with the same respective characteristics should have the same volume of trade. I don't think that lumping together multiple distances uner one DM implies that the trade volumes should be identical. Just that the differences fall below the scale of the model.

If he is indeed saying his rules are a crude model, then perhaps he won't mind my adjusting them somewhat to more effectively reflect this game's play.

No, why on Earth should he mind that? Why should anyone mind it? Are we discussing if the FT rules work or are we discussing if you're allowed not to use them if you don't like them? Because if it's the latter, there's not going to be any argument from me. You are allowed. I just thought it was the former.

I read the UPP. Handy thing, you should try it. Zila, for example has a Class E starport, a "Frontier installation. Essentially a marked spot of bedrock with no fuel, facilities, or bases present." (CT Book 3, etc.)

And yet The Traveller Adventure (a CT publication) describes Zila as a world with a flourishing interstellar wine trade with 5000T freighters used to pick up loads of wine (the frequency is not mentioned), starport workers, a startown district, and a Zilan Port Authority with a Customs and Immigration Department and an Import/Export Control Department. If something like that can be a Class E starport, obviously the definition you quote establishes the minimum required of a starport to get a Class E classification. If there isn't at least a marked spot of bedrock, it doesn't get to be Class E.

Admittedly, the next class up, Class D, seems to differ very little from the minimum needed to be a Class E (Unrefined fuel available and (presumably) some sort of staff. Frankly, I find it difficult to see how Zila's starport could be as described and not rate at least Class D, more likely C. Perhaps there's an element of bureaucratic obfuscation involved? Or perhaps the whole starport classification system is less than perfectly thought out? Perhaps it is a bit of a mistake not to take the astrographical relationships of a system to other systems into account when assigning starport class, instead of determining starport class randomly as the very first thing?

Zila, by virtue of its location on a trade route, ought to have at least a class C starport in the first place. Evidently the authors of TTA (who included Marc Miller) agreed and "solved" the problem by describing a Class C starport and pretending that it was Class E. If Marc Miller can do it, I'm not ashamed to do it too. To me a Class E starport is a bare spot of bedrock only if it makes sense that it is nothing but a bare spot of bedrock.

In any case, Zila's starport is one reason why I tend to pay less attention to starport ratings. (Another is Forine (Spinward Marches 1533), a system with 6 billion inhabitants and a tech level of 10 that is, and I quote, "the primary producer of processed and refined metals and minerals for [District 268]" -- and has a Class D starport!?!)

The Spinward Marches Sector trade map based on GURPS rules ...

http://images1.wikia.nocookie.net/_...eller/images/2/2a/Spinward_Marches_Sector.pdf

...tells us that this bare spot of bedrock serves no less than three feeder routes, averaging between twelve and twenty four "larger freighters" and "an equal number of smaller liners and free traders," serving an average 30,000 dTons of cargo weekly, with 6 to 12 ships every day offloading and then taking on 4000+ dTons of cargo at that "marked spot of bedrock with no fuel, facilities, or bases present" and then trying to scrounge fuel from the local seas. At least, so says the accompanying trade map key:

http://traveller.wikia.com/wiki/Trade_map_key

I've never tried to work out trade routes, so I can't tell if the person who did these maps used the FT rules correctly. I've no reason to think he didn't, and if he did, that part of the FT rules definitely doesn't work. Among other things the rules would seem to lack a provision for human correction of automatically calculated results.

Jump-2 trade between the Aramis Trace and Aramanx would have to go through Pysadi, Zila, and Carsten. Which is why there would hardly BE any regular jump-2 traffic between the Aramis Trace and Aramanx. They'd be outcompeted completely by jump-3 traffic through Zila.

Well, it breaks down for Class E starports, too. There being a whole lot of class E starports (93) and quite a few low pop worlds (150 with pop value 4 or lower, out of 439 March worlds), I think it becomes fair to question the value of a tool that gets it wrong for 1/3 or more of the cases it's applied to.

It's fair to question its value as a tool for the third of the cases it doesn't work for. I still find it useful for the cases it does work for.

Mercury (B658663-8), Strouden (A745988-D), and Lunion (A995984-D) each run "main" routes through Sharrip to each other. One has to presume Sharrip is only a waypoint; there are only 50 people on the world, the cargo is clearly not stopping there. The route from one through Sharrip to the other is 4 to 5 parsecs in two jumps. However, each of the three world also runs trade routes to good-sized neighbors within 1 to 2 parsecs of them.

I half agree with you. I can see no reason why trade between Mercury and Strouden would go through Sharrip instead of Gandr and trade between Mercury and Lunion could just as easily go through Capon. But most trade (anything that isn't time-sensitive -- that would go directly by jump-4) between Lunion and Strouden would go through Sharrip. If Sharrip's starport and population does not fit with that, the failure is in the world generation system that didn't take into account that Sharrip was located between two high-population worlds.

Could well be one of those "breakdowns" but, again, what good is the tool if it needs correction a third of the time or more? When it breaks down that often, the tool itself is in need of some serious tweaking.

Some improvement would seem to be distinctly possible, but in general I think that any automated system for generating simple answers to complex problems will need correction a lot of the time. A third seems a bit much, though.


Hans

 

[rancke]

Canon also says that it takes 4 days to deliver stuff from seller to the holds, Hans. (Bk7, p. 42) And it strongly implies 5 days to get people aboard from calling for pax.

It does. Evidently the authors failed to realize the existence and function of commercial factors. Since I can't think of any reason why commercial factors wouldn't work, I think that 'failed' is the operative word and that following canon that is based on that failure leads to more failure in turn.

And, since canon CT says both Bk2 and Bk5 ships coexist, and Bk2 2000 and 3000Td ships can carry for under KCr1/Td/Pc at one jump per 2 week...

The costs and operation rates are canonical - they're reinforced in Bk7, MT, and TNE. And T5.

The costs and operation rates are 1) based on false assumptions (to wit, the non-existence/complete ineffectuality of commercial factors) and 2) applies only to world-to-neighboring-world traffic. I even went to the trouble of cooking up an explanation of long distance traffic that didn't contradict canon for you. What more do you want?

And, if we add in the canonical but usually ignored travel times for travel from the stellar 100 diameter limits, a significant number of worlds are well more than a week from the jump point... I've not looked at the specifics - because I pointedly ignore the 100D limit of stars in my play - it's a hassle... tho', in my last campaign, I used them because Marc niftily provided handy tables for those limits in T5... Several of my mainworlds were 3-6 days in, and I used mass shadow but not target point masking, so you could come out anywhere outside the sphere, including the far side of the star.

You are so right about those travel times being ignored by the standard trade system. It's a failure that I've deplored on many occasions. But it doesn't affect your argument one way or the other, does it? That travel time would simply be added to the five days in port, destroying the canon times for those worlds anyways. Canon rules don't mention anything about radioing ahead with orders. You land, you discharge, you choose a new destination five days hence, and THEN you start looking around for cargo, freight, and passengers.

Simply put, even 14 days per cycle is pushing it unless you're maintaining system tugs and a jump-point "station" at all the deep wells... a place to stage cargo so it's ready for immediate load/unload near the jump point

Simply put, if a factor has goods waiting in warehouses and passengers lined up on 24 hour alert, a ship can land, unload, load and depart without waiting for the suppliers to deliver four days later. Under such circumstances a 10 day cycle is eminently doable even for world-to-neighboring-world traffic. Through traffic that only need to be refueled at a space station should easily be able to do it in 8.

- but you need enough so that all the ships arriving are outside each other's 36 hour windows...

Why is that necessary?

...and it's easiest if it's just pod-swap - but that's outside the realm of CT design systems.

But system shipping has costs, too....

Through traffic does not transfer its cargo, merely refuel in hours.


Hans

 

[robject]

I have no idea what amount of goods are produced on Earth today. I do know that it is a lot and also that the author of FT was a professional economist, so until someone actually proves differently, I'm going to assume he got his numbers right and high-tech, high-population worlds can produce that sort of volumes of trade goods his model comes up with.

Jim's a good economist, and knows his numbers. His formulae are fine, given his assumptions. I think he tends to see the Imperium as being a high-traffic setting. So if your assumptions about the setting require high traffic flow, then his book will work.

My assumptions require somewhat lower traffic flow.

Traffic levels in Traveller tends to be a "holy war topic". http://eaglestone.pocketempires.com/imtu-appendix-holy-war.html

 

[aramis]

The "not overlapping the windows" is how you minimize your warehouse space (and thus costs) - if you have more than 1 per 36 hour window, you need twice as much space (and that costs at least 58% more, if all you do is increase the size of the walls on the warehouse - CubeRoot(volume multiplier)squared change in materials needed.

As a practical factor, I'll note that Anchorage's Port can't push cargo out of the port into the state as fast as it can get it off ship... and vice versa. So it has to have dockside warehousing. Doable, possibly presumed, even if you have to use a trade station to maintain travel times...

Also, in re Factors - I've said that they are the most likely way to increase throughput on big freighters. You've argued in the past I'm all wet for saying "Merchant" in Bk3 trade is a man rather than a ship... but a factor is doing exactly the same with a warehouse.

Here's the thing: with a ship on a 10-day cycle, you must have an extra crew, because people tend to get weird when working more than 20 days straight. Most long deployments outside the sub fleet tend to have a liberty every month... and a 10-day cycle means little to no down time for the crew. So you need an extra crew. I can see stretching a crew to a month-on/week-off - 3 and 1, so you need 1.333 crews per ship and 3 ships to make it work. So, increase your 10-day crew costs by 33% for the off-duty crew. Also note that this of needs means they don't get back on the one they left - which isn't that big a deal, but is bad for morale.

Human behavior patterns put between 2/7 and 1/10 days as non-work days. (2/7 modern US & europe; 1/10, early shogunate japan, tho it wound up being 3/20, as the day before the rest day of the 10-day "week" is noted as haven often been a half day.)
if we split the difference, we get about 1/5 days, and 30 on needs 6 off.

The factor also needs time to get the cargos - and the 10% surcharge per day for early delivery of purchased goods cuts margins nastily. So he needs warehousing. Also, he needs a salary - since his skills are the same as a purser's, he should make about the same - each world adds a purser to the payroll.

Warehouse space should be much less expensive than ships on habitable worlds without trad-stations - at trade stations, or hostile environments, it's a no/low maneuver ship. I'd say probably about KCr1 per Td would be about right for habitable dirtside - amortize it in, with maintenance at the usual percentages.

Actually, since there is a canonical rental rate for warehouses, we can reverse engineer the cost of warehouse space - see T20 for the rental rates - and figure out what the heck the costs are by assuming a 30-50% profit margin for warehouse owners renting to tramps.

So your 10-day cycle has hidden costs that you're not factoring (pun intended), and while it will make somewhat more than a 14 day cycle, I don't think it will be enough more to make up for the losses due to stressed out crew - but there's no rules for that.

Other, more setting/story focused reasons for the 5 days dirtside - pulling PP & LS maintenance offline is probably 2-3 days of it, with the engineers getting 2-3 days shore leave. On a 14 day cycle, you can have a single crew.

 

[aramis]

Jim's a good economist, and knows his numbers. His formulae are fine, given his assumptions. I think he tends to see the Imperium as being a high-traffic setting. So if your assumptions about the setting require high traffic flow, then his book will work.

My assumptions require somewhat lower traffic flow.

Traffic levels in Traveller tends to be a "holy war topic". http://eaglestone.pocketempires.com/imtu-appendix-holy-war.html

Saying someone's a good economist is like saying someone's a good futurist - and Jim does both in GT - you can't prove or disprove it empirically except in the past tense, and past performance is little indicator of future success in either field. The field's most notable members certainly don't seem to be good at predicting the economy as a whole when they tinker with it at the national levels, and Jim's not one of the notables, even.

This is not to slight Jim at all - he's patient, kind, and good at math, and happy to help last I checked. But he admitted several items were basically guesses - effect of comm lag on trade volumes being a big one - and has stated that he feels comfortable with the number he chose as a minimum level of comm lag effect. He also was shocked at the trade volumes his assumptions worked out to, according to his TML posts. Before GTFT, he was a small-ship universe advocate.

He ignored the autonomy drive of colonial populations. I asked about that.
He ignored that, in pre-20th C populations, as trade volumes increased with population in absolute size, as a percentage, they held steady or decreased slightly during the colonial periods, as the colonies became more self-sufficient. He didn't include a factor for this effect at all... again, I asked. All we need to implement this is a multiplier of less than 1 on the population factor to UWTN, or to use CrTrade=x^(BTN) with X less than 10. But note also - 20th C data doesn't look the same. He used 20th C data.

He presumed all trade flowing at a roughly per parsec cost, apparently at the canonical GTU rates - which said rates I don't know the origins of the calculations of, and whether they work for GT ships or not. (I can find a few econ papers on prediction of response to price change, but can't make sense of them due to jargon.)

For simplicity, Jim treated all populations as similar in trade propensity - not a bad thing, but a break from realism. A needed one, because no stat regarding xenophbia/xenophilia and trade is canonically recorded. A random factor is worthy of consideration - but record keeping becomes an issue. For a private ATU, adding a stat may or may not be an issue.

GTFT is well written - but its a case of buying into the input assumptions, including the canonical-to-GURPS tech-level to average G$ incomes, the GT price tables for freight and passage, and Jim's best guesses and simplifications.

 

[Hemdian]

Traffic levels in Traveller tends to be a "holy war topic". http://eaglestone.pocketempires.com/imtu-appendix-holy-war.html

I hadn't noticed this before. Nice. But rather than "Strongly opinionated" you could have "Passionate".

(I'm OTU 80% jm-)

For simplicity, Jim treated all populations as similar in trade propensity - not a bad thing, but a break from realism. A needed one, because no stat regarding xenophbia/xenophilia and trade is canonically recorded. A random factor is worthy of consideration - but record keeping becomes an issue. For a private ATU, adding a stat may or may not be an issue.

Well there was the extended UWP from DGP that had just that stat, but I know that SJGames et al couldn't use that. Could the starport class imply the degree of xenophilia? I realise there are other factors that would affect starport class too, but it might make be a starting point.

 

[aramis]

I hadn't noticed this before. Nice. But rather than "Strongly opinionated" you could have "Passionate".

(I'm OTU 80% jm-)

Definitely "hot button" bordering on "Jihad"...

Well there was the extended UWP from DGP that had just that stat, but I know that SJGames et al couldn't use that. Could the starport class imply the degree of xenophilia? I realise there are other factors that would affect starport class too, but it might make be a starting point.

I don't think so, tho' lacking the facilities does seem to be a factor in Jim's equations. I'll note also that GT Class V to I ports are not actually defined the same as Traveller Class A to E ports, tho' they do map across well. Traveller doesn't define them as to minimum size, but GTFT does by implication on the starport type effect on trade flow. A class IV reduces trade flow on high UWTN worlds. A class I does so on any world bigger than a million GTL 3-5 people, or 100K people of GTL 6-8, or 10K GTL9-11 (TTL 8-13, roughly) or 1K GTL12+ (TTL 14+).

 

[Carlobrand]

Seems like I have to back down on some of my assertations. Unpleasant prospect, but it has to be done.

Don't feel bad. It happens to me all the time.

...I've no such reservations about high-population worlds in general or a few thousand T per year reaching Mora from Terra. But distances much higher than from one end of the Imperium to the other (and less than that for routes that leaves the Imperium) does bother me after thinking it over.

I rather like it for high pop worlds too, which is why I'd prefer to tweak it rather than give it up entirely. Unfortunately, since those maps have a lot of low pop and E-type worlds, I might have to give up the maps and do the work myself to factor out the problems - which is a bit irritating.

But it isn't entirely outside his field of expertise. However good or bad a basis terrestrial trade is for establishing interstellar economics[*] (How good a basis it is depends on how close the analogy is), it seems to me that it probably is better than no knowledge at all.

[*] Establishing, not judging. The man was creating rules for a fictive subject. That means that if what he says isn't demonstrably wrong, it's right.​

Acknowledged. He likely knows more about the history of economics and about various different economic models - including conjectured future models - than any 20 of us. I'm still brought short by the question of whether the fictive model he created for GURPS is appropriate for Classic Traveller. I don't know GURPS Traveller. I don't know if the assumptions implicit in that game, which may have influenced the economic model proposed for that game, are the same as CT's assumptions. He knows economics, and he likely knows GURPS, but does he know CT and was he thinking of CT when he developed this scheme, or are we trying to use a screwdriver to do the work of a hammer?

...I'm not able to show that you're wrong. I was saying that unless you could prove that a rule is wrong, the default assumption is that it is right.

As an example, I reject the rule that require regular ships to spend five days in port waiting for the suppliers to deliver the goods to the ship because I know for a fact that it's possible for a regular shipping line to have a factor and warehousing on a world and to buy the goods beforehand, have them delivered to the warehouse, and have them ready to load as soon as the ship has landed and unloaded its previous cargo.

I agree with you - partially. A Tukera liner on a scheduled route should have no problem turning around in a day, two at the outside: they know he's coming, the cargo should already be arranged, the tickets should already be sold, the only thing he needs is a bit of maintenance and supplying to prepare him for the next jump. An unscheduled Free Trader would have a few more problems - they have to arrange the bookings and contract for the next load of cargo - but a competent Class A/B starport should have the systems in place to facilitate that and get the Free Trader on his way as rapidly as possible, if for no other reason than to clear that dock for the next incoming freighter so they don't have to incur additional expense building more starport. Say an additional day. C/D - I think you're on your own and you'll probably be spending the full week arranging the contracts and finding passengers.

Canon was build around the week in port because it made it easier to calculate the passage in time, not because it was realistic. I'm not particularly troubled to violate that particular aspect of canon.

I don't even think that two different sets of worlds with the same respective characteristics should have the same volume of trade. I don't think that lumping together multiple distances uner one DM implies that the trade volumes should be identical. Just that the differences fall below the scale of the model.

Agreed, but for CT I think the model needs to be tweaked to a finer scale. Again, I don't know GURPS, it might be fine for GURPS, but there's a world of difference in CT between a jump-3 and a jump-5 cargo ship.

No, why on Earth should he mind that? Why should anyone mind it? Are we discussing if the FT rules work or are we discussing if you're allowed not to use them if you don't like them? Because if it's the latter, there's not going to be any argument from me. You are allowed. I just thought it was the former.

I started this by asking whether the FT rules work for CT. I know zip about GURPS - I assume they work great for GURPS. The question was whether thus GURPS rule could be lifted and applied to CT, or whether the differences between the two games were too great.

And yet The Traveller Adventure (a CT publication) describes Zila as a world with a flourishing interstellar wine trade with 5000T freighters used to pick up loads of wine (the frequency is not mentioned), starport workers, a startown district, and a Zilan Port Authority with a Customs and Immigration Department and an Import/Export Control Department. If something like that can be a Class E starport, obviously the definition you quote establishes the minimum required of a starport to get a Class E classification. If there isn't at least a marked spot of bedrock, it doesn't get to be Class E.

See there? Now I'm the one who has to back down on some of my assertations. CT says Zila's got nothing but a bare patch of bedrock for a landing field - which I take to mean there's not much in the way of shipping to serve, no need for warehouses and infrastructure - but CT also says Zila has a thriving interstellar export business including dockworkers, people whose livelihoods depend on serving the dockworkers, and a fairly significant bureaucratic structure focused on import and export. Personally, I think it needs to be promoted to Class-D, maybe call it a scouting survey error or something, but I don't get to make those calls.

Admittedly, the next class up, Class D, seems to differ very little from the minimum needed to be a Class E (Unrefined fuel available and (presumably) some sort of staff. Frankly, I find it difficult to see how Zila's starport could be as described and not rate at least Class D, more likely C. Perhaps there's an element of bureaucratic obfuscation involved? Or perhaps the whole starport classification system is less than perfectly thought out? Perhaps it is a bit of a mistake not to take the astrographical relationships of a system to other systems into account when assigning starport class, instead of determining starport class randomly as the very first thing?

Zila, by virtue of its location on a trade route, ought to have at least a class C starport in the first place. Evidently the authors of TTA (who included Marc Miller) agreed and "solved" the problem by describing a Class C starport and pretending that it was Class E. If Marc Miller can do it, I'm not ashamed to do it too. To me a Class E starport is a bare spot of bedrock only if it makes sense that it is nothing but a bare spot of bedrock.

In any case, Zila's starport is one reason why I tend to pay less attention to starport ratings. (Another is Forine (Spinward Marches 1533), a system with 6 billion inhabitants and a tech level of 10 that is, and I quote, "the primary producer of processed and refined metals and minerals for [District 268]" -- and has a Class D starport!?!)

Agreed on all points. I'm pretty sure some of the people who wrote the world descriptions weren't paying a lot of attention to the UPPs. It'd be good to go back and change some of those UPPs to support the adventures and such that have come out since. Maybe add that to the Errata project.

 

[aramis]

Zila's class E because they don't sell fuel. You have to refuel elsewhere in system.

 

[rancke]

The "not overlapping the windows" is how you minimize your warehouse space (and thus costs) - if you have more than 1 per 36 hour window, you need twice as much space (and that costs at least 58% more, if all you do is increase the size of the walls on the warehouse - CubeRoot(volume multiplier)squared change in materials needed.

I can't see any relevance to how fast a ship can refuel, and if it was relevant, the comparative value of a multi-million credit vessel and a warehouse would mean that if having half-empty warehouses most of the time was the price of getting more use out of your starships, companies would build warehouses that were half-empty most of the time. (Depending on just how much extra use they got out of the ships, of course).

Also, in re Factors - I've said that they are the most likely way to increase throughput on big freighters. You've argued in the past I'm all wet for saying "Merchant" in Bk3 trade is a man rather than a ship... but a factor is doing exactly the same with a warehouse.

I have? I can't recall in what context and concerning what argument I've done so.

Here's the thing: with a ship on a 10-day cycle, you must have an extra crew, because people tend to get weird when working more than 20 days straight. Most long deployments outside the sub fleet tend to have a liberty every month... and a 10-day cycle means little to no down time for the crew. So you need an extra crew.

Perhaps you do or perhaps you can instead pay them really good salaries. Like Cr36,000/per year and more, for example. There are surely plenty of historical examples of sailors working on the same ship for months. But even if they are needed, crew expenses are about 2% of the yearly expenses I calculated for the two examples above. And that's with the overblown crew numbers I got from the HG rules for military ship designs. If doubling the crew was the price of reducing a 14 day cycle to a10 day cycle, it would be very much worth it.

What's the tours of duty of oil rig workers?

I can see stretching a crew to a month-on/week-off - 3 and 1, so you need 1.333 crews per ship and 3 ships to make it work. So, increase your 10-day crew costs by 33% for the off-duty crew. Also note that this of needs means they don't get back on the one they left - which isn't that big a deal, but is bad for morale.

The work shedule would depend on the length of the route.

The factor also needs time to get the cargos - and the 10% surcharge per day for early delivery of purchased goods cuts margins nastily. So he needs warehousing. Also, he needs a salary - since his skills are the same as a purser's, he should make about the same - each world adds a purser to the payroll.

The warehousing I took for given. And, yes, I'm not including the groundside establishment in the calculations because I don't have ballpark figures. If someone comes up with reasonable figures, I'll include them. But they all seem pretty small compared to the operating expenses of the ships themselves.

Actually, since there is a canonical rental rate for warehouses, we can reverse engineer the cost of warehouse space - see T20 for the rental rates - and figure out what the heck the costs are by assuming a 30-50% profit margin for warehouse owners renting to tramps.

Small aside here. You're basing your profit margins on present-day economic conditions with a measurable yearly inflation rate. Traveller economies are based on an inflation rate that makes bank loans for starships 6.25% p.a..

(If we believe canon, these are loans to people with business plans that basically amount to "I'll jump around and pick up enough leavings of the regular lines to stay in the black", surely not the safest of loans. If free traders can get loans at that interest rate, who knows how much lower interest a well-established company can negotiate?)

So your 10-day cycle has hidden costs that you're not factoring (pun intended), and while it will make somewhat more than a 14 day cycle, I don't think it will be enough more to make up for the losses due to stressed out crew - but there's no rules for that.

There are hidden costs that I'm not including, true. But those hidden costs are comparatively modest, and talking of stressed-out crews is pure hyperbole. In any case, I'm quite willing to assume sheldules like two monts on, one month off. This would work out nicely for the hypothetically average long distance run of three systems: One month out, one month back, one month off duty.

(Whether a company would be paying for the off month is open to argument. Cr3000 per month for two months would work out at Cr24000 per year, the roughly average for a citizen on a tech level 15 world. Perhaps free trader crew are paid so high salaries because they're influenced by salaries that are meant to be stretched over month-long downtimes.)

Other, more setting/story focused reasons for the 5 days dirtside - pulling PP & LS maintenance offline is probably 2-3 days of it, with the engineers getting 2-3 days shore leave. On a 14 day cycle, you can have a single crew.

That's for player characters on tramp merchants. PCs don't usually serve as crew aboard long-distance interstellar transports. If they did, I daresday they would have their adventures in their months off.


Hans

 

[rancke]

Zila's class E because they don't sell fuel. You have to refuel elsewhere in system.

Which makes no sense for the reasons mentioned in a previous post..

(Also, at the level of detail TTA goes into with respect to running the campaign, the trips to the gas giant in the Zila system is a very odd omission.)


Hans

 

[rancke]

I agree with you - partially. A Tukera liner on a scheduled route should have no problem turning around in a day, two at the outside: they know he's coming, the cargo should already be arranged, the tickets should already be sold, the only thing he needs is a bit of maintenance and supplying to prepare him for the next jump. An unscheduled Free Trader would have a few more problems - they have to arrange the bookings and contract for the next load of cargo - but a competent Class A/B starport should have the systems in place to facilitate that and get the Free Trader on his way as rapidly as possible, if for no other reason than to clear that dock for the next incoming freighter so they don't have to incur additional expense building more starport. Say an additional day. C/D - I think you're on your own and you'll probably be spending the full week arranging the contracts and finding passengers.

The CT rules apply the exact same procedure for free traders in Class A starports as they do for free traders in Class E starports. You arrive cold, you select a destination and a departure date five days down the road, then sait back and wait for the passengers and freight to show up. If you like, you get one throw to find a suitable cargo for speculation. Presumably this is where tha four day delivery time comes in.

Canon was build around the week in port because it made it easier to calculate the passage in time, not because it was realistic. I'm not particularly troubled to violate that particular aspect of canon.

It's not a week in port, it's five days and a few hours. Reflected in the starport fees being for six days rather than seven.

Agreed, but for CT I think the model needs to be tweaked to a finer scale. Again, I don't know GURPS, it might be fine for GURPS, but there's a world of difference in CT between a jump-3 and a jump-5 cargo ship.

The difference, while real, is pretty irrelevant. Very little cargo would be shipped by jump-5 cargo ships. Almost all of it would go by jump-2 or jump-3.

I started this by asking whether the FT rules work for CT. I know zip about GURPS - I assume they work great for GURPS. The question was whether thus GURPS rule could be lifted and applied to CT, or whether the differences between the two games were too great.

What CT establishes about regular trade is so sparse and vague that a great many different sets of rules and setting assumptions could be applied to them. Up until the day TPTB selects one. At that point, the other umpteen becomes invalidated. There are a few tantalizing hints about regular companies, including mentions of multi-thousand tons freighters. There's a detailed description of one small company (Al Morai) that is, unfortunately, completely broken (it has Al Morai routinely using jump-4 ships on jump-1 legs).

The GTU is supposed to be identical to the OTU up until a change point in the very recent past. The authors tried their best to make that true (within the limits imposed by having to stick to GURPS basic rules (which IMO introduced some clear mistakes)). As you've made me realize, there are problems with low-population worlds and with trade routes. But they are equally wrong for the GTU and the OTU. Those bits won't work for the OTU, but they don't work for the GTU either. (Bummer! )


Hans