Thanks for the comments Phil.

On 24 May 2014 01:17, Postmark <postmark.design@btinternet.com> wrote:

On 23 May 2014, at 17:31, Timothy Collinson <timothy.collinson@port.ac.uk> wrote:

> Thoughts? (have I done my math right?)

I don't agree with just adding the percentages together and then multiplying, instead try
multiplying each percentage in turn so that it becomes progressively more expensive to
make things better and harder to make things cheaper.

So am I understanding you correctly to say that, for example,

QREBS 8 0 -1 0 +3

would mean not 17% added on (15% -1% +3%), but 45% (15 x 1 x 3)?

Yes, that would definitely give larger variations. But they'd be way too large at the extreme ends of QREBS. Let's take A +5 +5 -5 +5 for example. That would give a price modifier of 3125%. So for the air/raft example at Cr275,000, this top flight (no pun intended!) model would now cost Cr8,868,750. Wow. (Assuming I've got my sums right).

Of course another way of doing similar would be to have each of the REBS values count as a 5% increase/decrease like Q instead of the 1% I have.

I did actually consider this originally but thought it would give too great a variation to be believable. (I nearly kept Q at 1% but that didn't seem to do enough).

So, let's try that again. Cr343,750 for the air/raft above (+25%). And I make that +125% for QREBS A +5 +5 -5 +5. So Cr618,750 for the top end model. Which at least seems more reasonable as I guess (without looking in detail) that's more like the present day car variation. Still seems rather expensive in Traveller game terms though.

However, doing the same for negative QREBS values doesn't seem to work. The junker with QREBS 0 -1 -1 +1 -1 is -125% and they're paying you take it away, as I make that Cr -68750. Under my original system it would be -29% and Cr195,250.

I thought for a moment that was too high for a piece of junk but remember this isn't trying to model second hand prices. Which can be anything depending on the market. Just those from new so it doesn't seem quite so unreasonable.

I suppose you could set a limit of 15%, say, for any individual negative QREBS value so that at most it could be -75% (air/raft now Cr68,750) but I was trying to keep it simple and that looks to me as if it could only, realistically, be a second hand price.

Also the price ranges won't be big enough - I looked up the price range for a Ford Ka vs a Ford Mondeo and it is nearly 4x between the cheapest Ka and the most expensive Mondeo.

So on the plus side making them each 5% isn't so far off. On the negative side it doesn't really work. Hmmm, back to the drawing board. Or is this why Marc didn't include such a factor in the Core book?!