Investigation of Experience Points (chevrons)

[Simetrical]

For those who don't know, by the way, the Fibonacci series goes 0, 1, 1, 2, 3, 5, 8, 13, 21, 34, 55, 89, 144, 233, etc.: you add the previous two numbers to get the next one. What JeromeGrasdyke probably meant is that it would take x experience to reach the first level, y to reach the second, x + y to reach the third, x + 2y to reach the fourth, 2x + 3y to reach the third, etc.

-Simetrical

[QwertyMIDX]

The question about units not killing a single enemy and still gaining experience remains...perhaps there is carry over from previous battles and some sort of base amount given for taking part in a battle?

[Epistolary Richard]

I think we have to conclude that.

Before we can properly do the kill-numbers we need to know what is the 'participation' XP (aka the 'well, thanks for coming anyway' XP).

The only way to test it, though, would be starting up a campaign and trying to include a unit in as many battles as possible without it killing anyone until it finally levels up.

[roguebolo]

Jerome stated that sometimes at the end of the battle if the two sides were approximately equal they were sometimes awarded an experience bonus in addition to that accumulated by their kills.

[ZZR Puig]

I'll post a few examples of my experience, these are not controlled condition tests, but I think that may be helpful.

The first one is related to the units merging. Happened to me sometimes that I merged two units (about 2/3 of full strength) with EXP 1 and as a result get one unit with EXP 1 and the other with EXP 2. So seems clear that in a unit may coexist soldiers with different EXP level. So when you transfer preferentially some of them with high or low experience the final EXP of the whole unit may change.

Another interesting event happened on a battle. I mistakenly left my general unattended and was charged by cavalry and infantry. I managed to fight back and finally rout the enemy units, but the size of my general unit was reduced to 1. I used my general to chase the enemy units and made a good amount of kills, so during the battle he reached gold chevrons from scratch or almost (perhaps he had 1 bronze chevron at the beginning). When the battle ended a few of the casualties taken by the general escort recovered (3 or 4 if I'm not mistaken) and I then noticed that the resulting general escort unit had only increased their experience to level 3, not EXP 9 as my general already had.

I also think that the kills needed to raise experience may depend on the unit that is inflicting the casualties. If we agree that the kills needed to gain EXP are taken into account as kills per men of your unit, then smaller units, like cavalry, arcanii, etc. should increase their experience faster than bigger infantry units with the same number of kills. A few days ago I fought a battle where the enemy sallied forth. I made good use of my unit of mercenary elephants (36 men in large unit size) and killed 458 men. My elephants had EXP 1 or 2 at most and they didn't gain any additional experience in
that battle. Probably many of that men where routing, as enemy units don't stand fighting for too long when charged by elephants, but even taking that into account I think that this doesn't fit to my previous experience. My cavalry units (54 men each) would surely increase their experience at level 1 or 2 with so many kills, even with routed units. So perhaps there is something odd here.

As has already been said, I also noticed sometimes that the EXP of a unit is decreased when entering a battle, so there is some kind of differentiated treatment of EXP inside and outside battles.

I hope this can be of some use.

[A.Saturnus]

I tested your observation about elephants in a custom battle.
A unit of Carthaginian armoured elephants (36) killed 63 peasants in ranged and melee. The game halted when the peasants routed so the number of routers killed should be 0 or close to. The experience level of the elephants was 0 and they did not gain a chevron.
In another test, when the elephants killed 155 peasants, they did earn one.

[ZZR Puig]

I'm not sure which is the usual number of kills per men to reach the first XP level, but 155/36 = 4.3 seems to me that is much more than the usual. Perhaps someone could check, I'll try do do it myself if I have enough time.

[k@mi]

just something from the game itself that I think many of us noticed, but I would like to mention for those who might not have.

When a unit fights in melee combat, the first units are the ones that get the kills... the down side is that they also are the first to die.
so what you have a is a sort of seesaw
your guys kills enemy, other enemy kills your guys, repeat
i found this very amuzing when my Hastati where fighting in the enemy town square.
one of my guys would kill an enemy, and then another enemy would kill my guy who probably just gained 1 XP
also, this pertains to the units avg exp.
if only the front guys fight, then only they get the kills

so if you have a front guy who has just killed four enemis and then dies, well you just lost 2 XP.

I hope you see where im going with this.


a mini experiment that might be worth trying is to string your guys out in a very thin line and try to flank the enemy, my guess is that if your superior, then more of your guys get kills, there by raising you avg XP.

Hastati vs pesants
and make the hastati as thin as possible

[MajorFreak]

but the size of my general unit was reduced to 1.

ignoring the fact that general's unit size is different than retraining, the best way to go about testing is provided by ZZR. Grab a friend to play multiplayer, have a general unit on one side with maxxed out armour/weapons and on the other have a bunch of archers with maxxed weapons, plus the rest of the slots full of weak peasants.

turn the general unit so that the general is farthest from the archers, pelt away till only the general is left and then send him off against LOOSE formation, HOLDING pattern peasants (who have lots of flanking friends so they rout later than sooner)

• then you simply count the kills and the chevrons as they pop up

it's a shame you cannot modify the general's strategic command rating, nor his traits like "horribly scarred"

[Potemkin]

FYI: each man in a unit uses 4 bytes in a saved file

[Tigranes]

I don't know if this will help, but starting at nothing, a group of my peltasts gained 4 chevrons, with 869 kills.

[magnum]

A question specifically regarding elephants. As elephants themselves are mounts, and the mounts themselves can kill, do these kills count towards exp/chevron gain or does only the kills obtained by the riders count? With horse units its much easier as the horses themselves dont (at least I don't think they do) obtain kills. Could this be the cause of the seemingly high number of kills that are required to gain exp with elephant units?

[Uriel]

I'm wondering about Wardogs. Do kills from dogs count or is it just the handlers? Perhaps you can get experienced dogs and this experience is lost if the dogs are killed?

[TheViciousChicken]

I would certainly think so. I used a lot of wardogs against barbarians in my last julii campaign. Usually unleashing 4 wardog units into a town after breaking the gate.

Those dogs easily killed 600 to 800 enemies (warbands are unarmored light infantry, therefore easy to kill for wardogs) but since usually the all the dogs died no experience was ever gained by the unit.

By the end of my northern campagin some of this wardog units should have maybe 2000 to 3000 kills but still zero experience since most togs were lost in each battle. Must be tallied by the dogs than, not the handlers.

[Uriel]

Just wondering about retraining with 1.3. Does this repopulate the units with inexperienced troops or at the average experience of the unit?

Any observations?

[Kraxis]

Just wondering about retraining with 1.3. Does this repopulate the units with inexperienced troops or at the average experience of the unit?

Any observations?

The same as always... You still get 'free' experienced soldiers. So those 3-5 super experienced troops are certainly worth to keep clear of combining and send them home to be retrained.

[Willie McBride]

Yes- if by "free," you mean pay extra for. So far as I can tell, there's a significant increase in cost to replenish a highly-experienced unit.

[hellblazer]

Yes- if by "free," you mean pay extra for. So far as I can tell, there's a significant increase in cost to replenish a highly-experienced unit.

You just contradicted yourself. You said that you don't pay extra to retrain experienced troops and then said that there IS a significant cost increase to retrain experienced units.

[Willie McBride]

There is no contradiction- not if you define "free" as 'pay extra (cash) for.' These replacements are still "free" in that they start with the same high level of expertise without having to go kill several hundred folk apiece- presumably, they learn to kill from the core veterans who have seen the elephant.
This is not so outlandish as it might seem- after all, units retain their experience over hundreds of years in the game, although no individual would be in the ranks for than a couple decades. Rather, experience and esprit de corps must be handed from each generation of grizzled veterans to the green boys who come to replace them.

[Trithemius]

In BI it seems that sometimes after retraining experienced units I get a drop in experience. Perhaps the way in which units retrain has been altered for BI?

I also noted that I could retrain units trained elsewhere to benefit from the automatic experience increases granted by structures (i.e. I could retrain experience 1 Bosphorans in a town with a top-level Barracks and a top-level Kolaksy shrine and end up with experience 4 Bosphorans). As far as I know this is different from RTW.

[Willie McBride]

I have noticed in the most utd RTW (without BI) that I can retrain units with no experience to units with experience in a town with the appropriate temples. However, this does seem to require the appropriate bldg types as well, eg can't increase merc experience, and need high-level barracks to retrain high-level infantry.

[Artuk]

Hi,

I was reading through this about individuals in a unit having the experience and I have observed something when I combine units in BI that seems to contradict this. I have observed that when I combine a portion of a unit with chevron or two into another unit but have left overs, the left overs can go up in experience..

In example, I had a 2 chevron and a 3 chevron unit both damaged while playing as the saxons. I dragged the 2 chevron onto the three to fill it out. There were 7 men left and their experience actually went up leaving me with a pair of three chevron units.

At the time I figured that what happened was the unit unit experience pool is divided amongst the men remaining in it.. so when I transferred men out the amount of experience per man was increased.

This is anecdotal, and I didnt think much of it until I read this. I will try to reproduce it next time I play.

Regards,

Artuk

[magnum]

When combining units it is possible for a unit (either the one gaining or the one losing troops) to go up in level. It is also possible for them to decrease in level. Since RTW tracks exp on a per man basis, the chevrons displayed are simply an average of the exp of all the men in the unit. When two units are combined, RTW simply takes the needed number of men off the front of the giving unit and places them at the end of the recieving unit.

The only time if truely makes a difference is when you are planning on retraining a unit. Since replacements are of the avg experience of a unit, combining two units to possibly 'gain' a chevron allows you to get new recruits that are 1 chevron higher in experience. (Of course things go go the other way and your unit 'loses' a chevron of experience.)

[Stoneface]

I did some experiments.

Setup:
Custom Battle
Berserkers (gold weapons and armor) against peasants (no upgrades) defending a townsquare.
Fist slot was a token general, second slot the berserkers.
I only did two valid tries for zero and one chevron so the numbers should be taken with care.

Results:
The berserkers needed to kill 47 peasants on the first run and 45 on the second run to gain the first chevron. On the second run they lost one man.

To go from one to two chevrons they needed to kill 74 peasants on both runs.

They needed to gain a little less than two kills to get the first chevron and a little more than three for the second.

Conclusion:
I think CA uses "Gimli's rule for counting slain enemies" i.e. everything that isn't routing counts as one. Also War and Armored Elephants may count for three. "Experiments" with berserkers against a town full peasants also support this.

A unit needs about twice as many kills to gain its fist chevron as it has men. This is in line with my game experience.

I think CA counts kills for each soldier individually. The way some units gain experience while merging supports this.

Things I do not (yet?) know:
Is the average experience rounded to the nearest or rounded down.
The exact number of kills a soldier needs to gain a certain chevron. It may be only one if the displayed experience if rounded down and up to three if rounded to the nearest.

Further experiments required maybe with more armor and hitpoints for the berserkers and more moral for the peasants and outside town.

Edit 1:

Upgrades my berserkers and increased their armor, defense and hitpoints by ten. Also gave peasants a morale of twenty. More of this later.

Berserkers against Chosen Swordman. Battle setup as above.

Berserkers needed 46 and 49 kills to get the first chevron. This pretty much confirms the "each dead enemy counts as one" rule. Cavalery and chariots still have to be tested.

Soon to come:
An estimation of kills per man required to gain the first five chevrons by 24 berserkers and 601 peasants

The effect of distribution. Comparing Missile and Phalanx gaining experience by slaughtering helpless peasants.

Edit 2:

After a long time I came back to some chevron resarch. I did five runs of the 24 berserkers against 601 peasants.

Results:
1st chevron at 55/46/55/50/57 average 2.2 kills per man
2nd chevron at 134/127/134/138/133 average 5.6 kills per man
3rd chevron at 206/217/206/215/230 average 9.0 kills per man
4th chevron at 314/310/314/307/308 average 12.9 kills per man
1st chevron at 428/438/428/416/411 average 17.7 kills per man
I didn't go beyond five chevrons, because of the enormous number of peasants required.

A note on distribution: I do not have any good data yet, but slingers seem to need less kills per man in comparision to phalanx. Phalanx a bit more than the berserkers, slingers about 1.9 kills per man. Playing with the numbers revealed no hint of an possible algorithem so I believe CA counting method is a pretty obscure one.

Any comments an further research welcome.

[magnum]

Actually the difference you are seeing can be explained by the difference in the two types of units and how they kill. Remember, what is being displayed is the average level of the individuals in that unit. So some points to remember as you look at your data:

1) All slingers can attack (and thus get a kill) at the same time and so can advance at roughly the same rate as the others in the unit.

2) A Phalanx unit however only the front rank(s) can attack and get kills. The further back you go the less likely they are to get a kill.

The experience series goes roughly like 1, 1, 2, 3, 5. So for example take 2 40 man units, one slingers, one phalanx. The slingers kill 40 men, 1 each. The displayed exp is 1 (rounded down). Phalanx killed 40 men also, the front rank of ten men killed 4 each, while the other 30 men killed none. So 10 men have level 3, while 30 have level 0. Average displayed (rounded down) is 0.

Now the thing to remember is that is just the displayed information. Its used for nothing other than letting us the player have an idea what level of performance we can expect from that unit. The game doesn't care about that, its using the actual experience level of each individual soldier. In the above example, the front 10 phalanx troops are exp level 3 and since they're the only ones actually fighting they're not to bad.

Both the experience needed to level (1, 1, 2, 3, 5) and the rounding down are examples only. I don't know of anyone who knows exactly how many kills it takes to go up in each level. And as far as rounding goes, again no one knows for sure and in my opinion the game actually uses different rounding methods for the displayed exp level at different points in the game.

What I'm trying to show is how it could easily appear that some types of units require more kills to level than others when in reality (err, in game) it's just a matter of how those kills are spread amongst the unit members.

[econ21]

In the above example, the front 10 phalanx troops are exp level 3 and since they're the only ones actually fighting they're not to bad.

Interesting, but if it's always the same guys at the front that fight, doesn't that make the units experience level very fragile? The guys at the front are almost always the ones who will die, so does that not mean the unit will find it very hard to get to a high experience level as the vets are gradually culled? Loses for the slingers will be much less troublesome.

[Stoneface]

Actually the difference you are seeing can be explained by the difference in the two types of units and how they kill. Remember, what is being displayed is the average level of the individuals in that unit. So some points to remember as you look at your data:

1) All slingers can attack (and thus get a kill) at the same time and so can advance at roughly the same rate as the others in the unit.

2) A Phalanx unit however only the front rank(s) can attack and get kills. The further back you go the less likely they are to get a kill.

You found the reason for my test setup. Good

The experience series goes roughly like 1, 1, 2, 3, 5.

Sorry, I am quite sure this is not even remotely in the right area. Please quote your sources so we can find the reason why they contradict with my research.

So for example take 2 40 man units, one slingers, one phalanx. The slingers kill 40 men, 1 each. The displayed exp is 1 (rounded down). Phalanx killed 40 men also, the front rank of ten men killed 4 each, while the other 30 men killed none. So 10 men have level 3, while 30 have level 0. Average displayed (rounded down) is 0.

So I thought too but I am pretty sure I was wrong. The difference just isn't big enough. Assuming that only a quarter of the unit does the killing and the fourth chevron takes at least 12 kills (average 12.9 in the berserker vs peasants test) the phalynx unit would need 3 kills per man for the first chevron. The actual number is around 2.3. If you do not believe me run your own tests.

What I'm trying to show is how it could easily appear that some types of units require more kills to level than others when in reality (err, in game) it's just a matter of how those kills are spread amongst the unit members.

Yes, I am pretty sure it is. But I am also pretty sure there is a more complicated calculation going on. If the spread is uneven a different member of the unit might be awarded the kill or something like that.

Sorry I got a bit lazy in the end and was not as clear as I wanted to be.

[Severous]

Hi

Some interesting observations and research on this forum and in this thread.

Do you think soldiers may gain experience without killing anyone ?

The act of attacking, defending, firing ? Just being in a battle?

I had a small barbarian cavalry unit gain a level of experience without inflicting or sustaining any casulaties. It did run through an enemy unit. Not to attack it but because it was in the way. There were a few clashing sounds but no casualties.

[magnum]

As far as where I got 1 1 2 3 5 etc, it was stated by a dev that the kills needed for advancement was LIKE the Fibonacci series (which is 1 1 2 3 5 etc). It was re-stated earlier in this thread. Now the dev said like, so I'd take that to mean not exactly. However it would be reasonable to assume that because what the devs have said, it takes increasing numbers of kill for each level of exp.

As far as front rank earning the kills making melee units rather easy to gain/lose experience your are correct. In the battle screen if you watch a unit you can sometimes see that happen as a unit pops up and down 1 level of experience as the front rank kills or are killed. I have no idea if the location of the men in formation is static from one battle to the next nor how replacements are added / removed from a unit. So this battles front men might not be next battles front men.

Finally, in response to Severous2's query. CA has stated that in battles where the sides are roughly equal (they didn't say what represented roughly equal) that 'bonus' exp is awarded to all units that participate in the battle. So yes, a unit can gain exp even if they never engaged, simply for being on the battle field.

[General4Hire]

I suspect it's hopeless. There have been ample anecdotal reports of units not participating in the battle and still gaining experience. I should think that there are lots of factors, quite possibly including some random ones. I doubt there's any way to properly isolate them.

-Simetrical

Is it possible that some general's retinue includes "experience for all troops in a battle"? Maybe this is hidden at times? who knows...heh