Store pricing weirdness

[awldune]

I've been away from the forum since 3.10 and recently stopped in to check out 3.12. I have noticed some strangeness in the pricing of items.

I thought this was intended as a rebalancing (shooters seem more expensive) but I have seen some things at very oddball prices. I seem to remember I bought a ring of damage at black market and it was 30,000 instead of the expected 5-6k.

Just now I went into the armor shop, and there are a pair of sandals of speed +5. The price? 9,783!

Otherwise I have been enjoying some of the enhancements in 312. Targeting change is good, artifact changes are nice. I am actually using Glondricam now and considered Elvagil.

[Magnate]

I've been away from the forum since 3.10 and recently stopped in to check out 3.12. I have noticed some strangeness in the pricing of items.

I thought this was intended as a rebalancing (shooters seem more expensive) but I have seen some things at very oddball prices. I seem to remember I bought a ring of damage at black market and it was 30,000 instead of the expected 5-6k.

This is indeed a consequence of the intended rebalancing. Damage rings are good, and the BM is expensive.

Just now I went into the armor shop, and there are a pair of sandals of speed +5. The price? 9,783!

Ah yes. There are two problems here: one is that speed items shouldn't appear in non-BM shops at all (cue more long debates about games of shopping). The other is that the value of the speed pval is curiously nonlinear. +1 speed is really not worth very much, and +12 speed isn't worth much more than +11, but in between all sorts of interesting things happen with the curve. I've been trying various arrays for the values of +speed and freely confess that none of them has been quite right. (Eddie will chime in at this point and say that the whole basis of valuation is wrong, but that's an orthogonal issue IMO.)

Anyway, here are the current values, in case anybody feels like sticking their neck out and proposing a better set:

static s16b speed_power[21] =
{0, 10, 21, 33, 46, 60, 75, 91, 108, 126, 145,
163, 180, 196, 211, 225, 238, 250, 261, 271, 280};

I think it needs to ramp up more quickly between +2 and +7 but without increasing the values in the 14-20 range (as the marginal values of those points are a lot lower).

Otherwise I have been enjoying some of the enhancements in 312. Targeting change is good, artifact changes are nice. I am actually using Glondricam now and considered Elvagil.

That's really good to hear - thanks for that.

[PowerDiver]

Anyway, here are the current values, in case anybody feels like sticking their neck out and proposing a better set:

You should calculate values in the most useful case. So e.g. to figure out the value of an avg arrow, assume a ranger is shooting it at a dragon using Bard. As to speed ...

You need +20 speed to fight M. That assumes a temp speed boost on top. The +20 together stops you from being double-moved, which essentially halves the number of hp you are required to have. So from that alone, +20 speed = +100% "value". In addition, at +20 speed each point of speed is worth about +3% damage. My last warrior was doing 100 damage per blow, so I'd say a good starting point is +1 speed = +5% + +3% = +8% = +8 damage. You may quibble with 100 per blow, but it gets even worse when you assume ranged attacks from a mage or ranger who value +dam not much at all.

You will say that many chars will prefer a +40 damage ring to a +5 speed ring, and that is true, but irrelevant. That comes down to rarity issues, which you still haven't tackled yet. If you had to face M and had a choice between +10 speed with +80 damage or +20 speed from two rings, with no other speed items, which would you choose? That's a slam dunk for speed, but not a fair comparison either.

I am opposed to this whole approach, but if it is the future of V I figure I have to chime in anyway. I think you should use a value between +5 and +10 damage for each point of speed.

[Magnate]

I am opposed to this whole approach, but if it is the future of V I figure I have to chime in anyway. I think you should use a value between +5 and +10 damage for each point of speed.

I love the fact that you can write a full exposition with which I agree completely, and then reiterate how much we disagree.

Your conclusion is particularly gratifying, since each point in the speed array corresponds to half a point of damage. So +1 speed is currently valued at exactly +5 damage, with every other point of speed worth between +5 and +9.5 (except the 20th, which is worth +4.5 - but the problem with the upper end of the scale is that it's valuing a single speed item, and although we cannot assume any other speed items, neither can we ignore their probable existence).

So we are actually very close on this issue - but IMO we're still getting values which are too low for speed pvals in the 2-8 range. Hence my original suggestion that perhaps we should look at something like +12 damage for those points, tailing off to maybe only +4 or +3 damage for the upper teens (due to the issue mentioned above).

[PowerDiver]

I guess the problem is rarity issues. Boots of speed +10 are probably worth at least 10 times as much as a ring of speed +10, because they are so much better than the alternatives, playing with standarts anyway.

[Magnate]

I guess the problem is rarity issues. Boots of speed +10 are probably worth at least 10 times as much as a ring of speed +10, because they are so much better than the alternatives, playing with standarts anyway.

Yes. I freely admit that this currently isn't a feature of the pricing algorithm, which will price them roughly equally.

[PowerDiver]

+1 speed is currently valued at exactly +5 damage, with every other point of speed worth between +5 and +9.5 (except the 20th, which is worth +4.5 - but the problem with the upper end of the scale is that it's valuing a single speed item, and although we cannot assume any other speed items, neither can we ignore their probable existence).

Rarity issues are separate. I think you should have a fixed power for each point of speed. At least extra speed helps a little -- much better than extra rFire.

However, for pricing, IIRC you price quadratic in power. Perhaps you need to up that to cubic. Then +5 would cost double +4 and perhaps +10 would be too expensive to buy, as it should be. Also, cubic is better than quadratic for items of negative power.

You don't seem to incorporate weight. A spear and rapier cost the same. Even ignoring blows issues [which of course are a big deal], I really think you need to factor 30 lb = -1 speed into your equations. If plate mail comes out with a negative power, so be it.

[Magnate]

Rarity issues are separate. I think you should have a fixed power for each point of speed.

Definitely not. The first point of extra speed is +10%. The 11th point is +5%. They are definitely not equal in value. The only reason it's not a smooth decline in power is because of the finite number of pvals (slots) with which to boost speed, hence +5 on one item is actually more useful than +1 on five items. That's not a rarity issue - you are right that those are separate.

However, for pricing, IIRC you price quadratic in power. Perhaps you need to up that to cubic. Then +5 would cost double +4 and perhaps +10 would be too expensive to buy, as it should be. Also, cubic is better than quadratic for items of negative power.

Cubic might work better for speed, but not for everything else, and I don't really want to change the paradigm to fit the corner case. Eventually we will settle on a power array for speed which generates both sensible prices and sensible randarts.

You don't seem to incorporate weight. A spear and rapier cost the same. Even ignoring blows issues [which of course are a big deal], I really think you need to factor 30 lb = -1 speed into your equations. If plate mail comes out with a negative power, so be it.

I've been wrestling with how to reflect weight in power calculations for years. #1004 is the relevant ticket - it's definitely on my list. It's one of those that keeps getting postponed because the effort always seems more than the reward - essentially it's another set of corner cases. Now that we have calculate_melee_crits it might seem a bit easier after I've done #951.

[PowerDiver]

I really disagree with your "first point of speed" does something. There is no first, or last. They just combine. There is no difference between wearing two rings that are +3 to both con and speed, versus one ring of con+6 plus one ring of speed+6. The only thing that is important is rarity, which determines which you toss because you can replace it more easily on some other item such as your boots to let you wear a ring of acid instead.

Items have different values to different chars. That's not about power, but rather how they fit into the needs of the current situation.

[Magnate]

I really disagree with your "first point of speed" does something. There is no first, or last. They just combine. There is no difference between wearing two rings that are +3 to both con and speed, versus one ring of con+6 plus one ring of speed+6. The only thing that is important is rarity, which determines which you toss because you can replace it more easily on some other item such as your boots to let you wear a ring of acid instead.

There are multiple issues here. One is the issue of limited slots, which I mentioned before. +6 *does* have greater utility than 2x +3. The other is that damage (which is the entire basis of the utility calculation) is essentially linear (every point has the same value), where speed definitely is not. My use of "first" and "last" may have confused us both, but my issue is that the power difference between +11 and +12 should be less than that between +1 and +2.

[PowerDiver]

my issue is that the power difference between +11 and +12 should be less than that between +1 and +2.

You want to conflate power, value, and utility. They are separate. They cannot be combined. That is the source of our disagreement, and also why the game is great.

The power difference of speed boosts between +1 and +2 and between +11 and +12 is the same. It exactly counterbalances 30 lbs of additional weight for a char with at least 18/50 str who is carrying in excess of 150lbs, which is to say most characters most of the time when it matters.

The utility of the difference will vary. I would say the price difference should be much higher for +11 vs +12 than +1 vs +2 even though it has less proportional effect. All separate issues.

[Magnate]

You want to conflate power, value, and utility. They are separate. They cannot be combined. That is the source of our disagreement, and also why the game is great.

This is a very neat summary. I *have* to try and combine them, otherwise we have to go back to manual pricing of every item. I freely admit that it can never be perfect, but I'll keep trying to improve it. Thanks as ever for your input.