Everything about Corruption: C3C edition

[alexman]

I took a quick look.
Nice looking empire!
It certainly doesn't seem like it's worth burning a leader to relocate the Palace at this point.

Moving the palace to the north, where I would suspect it's going to be better in the long run (after you have developed the northern cities better), increases corruption. The problem is that you have more population to the south, so moving your palace to the north increases the city rank for a lot your population.

I think a Palace where your FP is now, and a FP to the north would be ideal for this empire.

[E_T]

We also recently got some inside information (a look at some of the actual corruption code), which helped find the last few missing pieces of the corruption puzzle.

Alexman, You are truely the Corruption Nazi!!!

But my question is, with this new information as to the missing peices of the previous corruption puzzle, does this have any effect on the older (Vanilla & PTW) version calculation models?? In other works, does that other corruption thread need to be updated?

Also, I know in PTW, there is a slight difference between a PBEM game and an SP game. Have you been able to quantify that yet? And has anyone assertained if the same applies to C3C??

E_T

[alexman]

Off the top of my head, things that have changed in C3C:

1. The FP does not affect rank.
2. The FP gives a higher OCN increase than before.
3. Communist gets a higher OCN increase than before.
4. Courthouses etc reduce maximum corruption
5. Specialists

The PTW corruption thread appears to have different numbers than this one, but it's mostly because I normalized the government coefficients by Despotism corruption and the trade coefficient by unconnected cities, whereas here they're normalized by Monarchy/connected cities.

I have heard you say that corruption is different in PBEM and SP before, but I have not seen it myself, and I have certainly not attempted to quantify the difference. If it happens, I doubt it's a difference in the actual corruption model, as there is no distinction in the code between SP and PBEM. My guess would be that the PBEM games pick up the wrong OCN (for a different size map).

[Arnelos]

Once again, great work on this.

Man, what on EARTH would we do without you strat forum guys on our site to help us out with stuff like this?

[robinguo]

The sum of the distance and rank components of corruption can be greater than 100%. The game sets an upper limit for the total corruption in a city to be equal to 90% minus 10% for each city improvement and minus 70% for each Wonder in the city with the “reduces corruption?ability:

Great works! Alexman!!
But may I ask a question about the upper limit,
does the "upper limit" actually worked in any situation?
is it means we can build courthouse and police station in
every city , and reduce the final corruption to 70%?

[player1]

Originally posted by robinguo But may I ask a question about the upper limit,
does the "upper limit" actually worked in any situation?
is it means we can build courthouse and police station in
every city , and reduce the final corruption to 70%?

exactly

[Nor Me]

I've just done a quick test for it and I think that all the OCN increases apart from those from courthouses, police satations and WLTKD are affected by difficulty level That would make the formula something like:

Nopt = max(OCN * (L/100 * (1 + c + Gr + Gp*Nwe) + 0.25*Ni), 1)

So courthouses really are more effective at higher difficulty levels but the commercial trait is not.

I'm not sure where all the rounding happens in the parts we haven't seen the code for but it can be significant. In PTW, the the OCN increase for the commercial trait was rounded down so if the OCN modified by difficulty level was just below 12, the increase would only be 2 and the corruption reducing ability of commercial would about a third less effective than it should be.

Another thing, there's no mention of WTLKD reducing disance waste. I've not tested it but I've seen it in the code.

[alexman]

Originally posted by Nor Me
I've just done a quick test for it and I think that all the OCN increases apart from those from courthouses, police satations and WLTKD are affected by difficulty level That would make the formula something like:

Nopt = max(OCN * (L/100 * (1 + c + Gr + Gp*Nwe) + 0.25*Ni), 1)

If you are certain of this, I'll update the initial post. Thanks. I thought I tested for it, but I could have made a mistake.

Another thing, there's no mention of WTLKD reducing disance waste. I've not tested it but I've seen it in the code.

Whoops, you're right of course.

[Nor Me]

I'm not certain yet, but it certainly doesn't work in the way your formula suggests. I know that in my test, a courthouse reduced corruption in one city by a factor of 6, for a commercial civ with an FP in Democracy when I modded regent to 1% of the OCN. That would seem to suggest that all these are affected by difficulty and courthouses aren't.

As it was a standard map, it might be that the modified OCN was 1 before the courthous which increased it by the expected 20/4.

I did tests with PTW that gave exact values and was surprised by your formula given the values I'd seen. Notably, the commercial rounding didn't seem to have any other explanation. But then I was surprised that the modified OCN was an integer so they can't have been that precise.

As I didn't look at exact numbers, there's a slight possibility that it's all one big rounding error for such an extreme value.

[fishleaf]

I suspect the exactness of the formula ALEXMAN posted.

[vulture]

It's not exactly exact - there are some rounding issues that don't appear in the formula. One that I remember from vanilla civ3 (don't know if it was changed in PtW or C3C) was that distance corruption, expressed as a percentage, was always an even integer. You could have 44% distance corruption, or 46%, but nothing in between, for example (possibly that was an artefact of some other curious rule, for all I know). And of course the distances are produced with a fairly odd formula as well, rather than the actual geometric distance between the cities.

But the formula doesn't need to be exact - what value does it have in the game to calculate corruption exactly, independent of the computer. The actual uses of the formula - determining where to put your FP, where to build courthouses and police stations, how to space cities - all these come from the overall form of the equations, which I'm confident that Alexman has nailed pretty accurately; they're not adjusted by the precise numerical details at the rounding-off-error level.

[alexman]

For the record, Nor Me is right that courthouses are more effective at higher difficulty levels but the commercial trait, better governments, and FP are not.

I already updated the formula when he posted his correction, and in the meantime I have verified that it is correct.

I will not even attempt to address rounding issues. It's too tedious to test, and as vulture says, we don't have much to gain from an exact formula.

[Aqualung71]

I'd like to weigh in with support of Alexman, Vulture and Nor Me here. I've taken a keen interest in the corruption calculations and have digested Alexman's calculations and formulas and applied them rigorously to "in-game" situations by manually calculating theoretical corruption percentages on a city-by-city basis, and I can confirm categorically that the formulas work very well without exception within quite small margins for error that can easily be explained by rounding differences.

I suspect that the adjustment proposed by Nor Me is probably correct, and I have no doubt that either way, the formulas give us a substantially correct estimate of corruption in all cases, with insignificant and very acceptable rounding errors within the context of the game. Trying to go any further and making the formulas absolutely precise serves no useful purpose in my view.

Again, for the exceptional work Alexman has put into unravelling the corruption mystery and kudos to Nor Me for spotting the minor amendment......as Vulture says, there is no value in trying to take it further at this point.

Great stuff guys!

[Rommel2D]

Originally posted by alexman
I will not even attempt to address rounding issues. It's too tedious to test, and as vulture says, we don't have much to gain from an exact formula.

Sure, elect a guy Emperor and he starts to neglect the kingdom. ;-)

[alexman]

Emperor?
Hey, I got promoted 15 posts ago, cool!