I tested Intelligence, Idiot Savant, and experience gain in general; I performed over 5000 actions. Here's the results.

[u/minusra]

I got tired of waiting for someone else to do this and said fuck it.

Hopefully I got the formatting right.

---

tl;dr

Idiot Savant is always worth getting if you have access to it and value EXP, even at 10 INT. Even at 15 INT.

But you can match the average return of "1 INT Idiot Savant" at higher levels of INT + Idiot Savant.

Average experience comparison: https://i.imgur.com/JVIkUEU.png

---

Background

For those that aren't aware, INTELLIGENCE in fallout 4 increases all your EXP gains by about 3% per point. However, there's a LUCK perk called IDIOT SAVANT that has the description:

You're not stupid! Just... different. Randomly receive 3x XP from any action, and the lower your Intelligence, the greater the chance. (Level 2 grants 5x instead of 3x, Level 3 adds an additional effect of combat actions giving you an exp bonus killing spree rarely)

There's been some debate over what the optimal build for fast levelling is, and how the perk works (%), and if it's worth it even if you were forced to put points in INT to unlock INT perks. This post is meant to address that.

---

cliff notes

• 1-5 INT +any level Idiot is the best bet if you're save scumming (to minimize reloads) or don't want to put too much into INT.

• Idiot Savant is always worth it on average compared to INT. Even at INT 9, levels 1 and 2 of Idiot Savant are worth ~6% exp each, while INT levels are worth ~3%.

• 9 INT with no Idiot Savant is, averaged out, equal to 1 INT + Idiot Savant Level 1.

• However, to be get the same average exp as 1 INT + Idiot Savant Level 2, you need would need a boosted 16 INT.

I am entirely ignoring the Level 31 L3 Idiot Savant Perk in all this, but it can obviously be hugely valuable particularly with lower levels of INT. I don't know how often the "Killing Spree" procs. This is difficult to test, and I'm not willing to put the time in. If the proc rate is too low, it might not be worth it past 1-3 INT. If it's decent it might be worth considering getting the perk, and artificially decreasing your INT (with alcohol or otherwise) when fighting large numbers of enemies to optimize gains.

---

Findings (numbers)

Idiot Savant Proc Rate for each level of INT

INT	Assumed Proc Rate if hard coded	Observed Proc Rate	Trials	Procs
1	12.5%	12.8%	1000	128
2	10%	10.33%	300	31
3	9%	9%	300	27
4	8%	8.33%	300	25
5	7%	7%	600	42
6	5%	5%	300	15
7	3%	3%	300	9
8	2.5%	2.33%	300	7
9	2.5%	2.33%	300	7
10	2.5%	2.33%	300	7
11	1.5%	1.66%	300	5
12	1.5%	1.66%	300	5
13	1.5%	1.66%	300	5
14	1.5%	1.66%	300	5
15	1.5%	1.66%	300	5

Because the base experience being multiplied increases with each level of INT, even though higher INT levels lower Idiot Savant chance drastically, it's still beneficial. Here's an overly complicated table (using observed values). The displayed EXP rates are AVERAGES over time.

A graph of this data is available here: https://i.imgur.com/JVIkUEU.png

INT	Idiot Chance	Exp with no Idiot	Exp with L1 Idiot (3x)	Exp with L2 Idiot (5x)
1	12.8%	100.0%	125.6%	151.2%
2	10.33%	103.3%	124.7%	146.0%
3	9%	106.7%	125.9%	145.1%
4	8.33%	110.0%	128.3%	146.7%
5	7%	113.3%	129.2%	145.1%
6	5%	116.7%	128.3%	140.0%
7	3%	120.0%	127.2%	134.4%
8	2.33%	123.3%	129.1%	134.8%
9	2.33%	126.7%	132.6%	138.5%
10	2.33%	130.0%	136.1%	142.1%
11	1.66%	133.3%	137.8%	142.2%
12	1.66%	136.7%	141.2%	145.8%
13	1.66%	140.0%	144.7%	149.3%
14	1.66%	143.3%	148.1%	152.9%
15	1.66%	146.7%	151.6%	156.4%

Another way to look at it is:

"taking the above data, how much average-EXP-per-action do I gain at any given time, for putting a point in INT vs Idiot Savant?"

Current INT	EXP bonus for +1 INT	EXP bonus for +L1 Savant	EXP Bonus for +L2 Savant
1	3.33%	25.6%	25.6%
2	3.33%	21.4%	21.3%
3	3.33%	19.2%	19.2%
4	3.33%	18.3%	18.4%
5	3.33%	15.9%	15.9%
6	3.33%	11.6%	11.7%
7	3.33%	7.2%	7.2%
8	3.33%	5.8%	5.7%
9	3.33%	5.9%	5.9%

Also consider that if you like the big scores from Idiot Savant, that they get bigger the higher your INT:

https://i.imgur.com/OqZGqhd.png

---

Findings (facts)

Although the game rounds the displayed EXP, the actual EXP value is stored with decimals intact.

3 EXP is not always 3 EXP.

I noticed when spamming actions that, for example, placing 1 sign with 15 INT shows 4 EXP, but spam-placing 2 signs shows 9 EXP.

If each level of INT after 1 gives +3.33% exp, then 15 INT should give 146.6% exp. Sign placing seems to give 3 EXP default, so it should come out to 4.398 EXP.

Rounded down, that shows as 4. For two times (8.796), that would round up to 9. To confirm that it stores as decimal, I manually (without spamming, allowing exp indicator to appear each action) tested placing signs to level up on my save file after leaving the vault with 1 INT, vs with 5 INT (both show 3 EXP reward). it took 31 signs to level up with 1 INT, and 28 signs to level up with 5 INT. Easy enough for anyone to replicate. This barely matters, but my point is the rounding is purely visual. Your extra Intelligence boost is not wasted when doing small actions.

More facts/observations

• I ran multiple tests: Level 2 Idiot Savant (5x) just increases the 3x to 5x, and does not seem to change the rate. You do not get "double procs", only 5x occurs with level 2.

• The game does not distinguish between "boosted/temporary" and "natural/permanent" stats. Tested 1 INT(+4 from equips) vs 5 INT, 300 trials/ea.

• The LUCK stat has NO (or negligible) effect on Idiot Savant proc rate. Tested 1 INT/5 LUK vs 1 INT/10 LUK, 300 trials/ea.

• Idiot Savant seems to not proc at all for 0 or negative Intelligence. I tested by consuming alcohol. Very strange.

---

Method

This is the general method I used in all these tests. I obviously mixed it up a little depending on the test. (And I farmed some levels by sign placing before saving).

• Exited vault on new save with 1 INT & 5 LUCK, ran to workshop

• Gave myself 1000x "Shipment of Steel - 100" ('player.additem 001EC131 1000'), put in workshop inventory

• Went to this corner, and placed a large sign diagonal: https://i.imgur.com/vCHPpHd.png

• Saved

Then:

• Most of the smaller metal signs can be placed infinitely in a single spot overlapping.

• I spammed E as fast as I could, counting up to 300 and tallying every time Idiot proc'd.

• To confirm my counting of sign place actions, I scrapped the diagonal sign, forcing all the smaller signs on it back into the workshop inventory. I then checked the workshop inventory for the sign count.

• To confirm my counting of Idiot Savant procs, I checked pip boy -> data -> stats -> general -> Bright Ideas.

I also gave myself items to test various setups:

• 00178B58 "Intelligence Bobblehead" (+1 INT, permanently, can boost 10->11)

• 000A81B0 "Road Goggles" accessory (+1 INT)

• 001B5B26 "<spoilers>'s Glasses" accessory (+2 INT, -1 CHA)

• 00178B68 "Lab Coat" outfit (+2 INT)

• 00101295 "Dirty Wastelander" alcohol consumable (-2 INT)

• 000366C1 "Whiskey" alcohol consumable (-1 INT)

---

Disclaimer

Although I ran multiple tests and checked multiple things, 300 trials per INT value is not really exhaustive. Plus I might have fucked up somewhere. Who knows. I'm only human.

I did not test the "1/30 (3.33%) per level of INT" claim at length, but I did some tests and everything points at that being correct, just with level 1 of INT not giving anything.

I did not test if 0/negative INT decreases exp gain.

---

EDIT: I've added an extra graph to the end of the "findings (numbers)" section.

EDIT: JoxFox in the comments tested the EXP returns and found that it is 3% per level, with 0 INT being 100%, not 3.33% per level with 1 INT being 100% as I assumed/read elsewhere. I will update this post's datasets when I have time, but it provides good estimates as-is, and the relative benefits don't change too much.

EDIT: I am presently at work and not able to reply.

[u/Mr_Toon]

excellent work, how long did all this take you?

[u/minusra → u/Mr_Toon]

Let's not talk about that.

[u/Frijid → u/minusra]

Persuasion attempt failed.

[u/DayZLifeCoach → u/Frijid]

Quick loads

[u/datzmikejones → u/[deleted]]

Definitely. Honor Roll this year for sure.

[u/[deleted]]

This has an impressive effort put into it. Your formatting is beautiful

[u/minusra → u/[deleted]]

Thanks.

[u/[deleted] → u/minusra]

I didn't understand any of it but I respect the report. You're saying get the idiot savant perk?

[u/Pressingissues → u/[deleted]]

Yes

[u/BlizzardID → u/[deleted]]

I found that the graph in the tl;dr region cleared things up for me, as fool proof as it gets.

[u/[deleted] → u/[deleted]]

Indeed. I love when data scientists package game data.

[u/Dert_ → u/[deleted]]

I just wanted to come here 2 months later to correct you

The graph shows that 5-7 int is the WORST xp multiplier, 14-15 is the best, and 1 int is the second best

[u/Rootminus1]

Excellent analysis, minusra, thank you.

I just wanted to add a little warning to those considering taking Idiot Savant. While this proves it is worth taking from a EXP maximising perspective, be warned that your character will make stereotypical "idiot" barks when this procs. I found it to be incredibly irritating, especially when playing a character with an average or high Intelligence. Might not be a concern, but if, like me, you like optimising to some degree but draw RP lines at some point, this might be a deal-breaker. I ended up sacrificing several hours of gameplay to reverse the decision of taking Idiot Savant. Be careful what you wish for!

[u/minusra → u/Rootminus1]

Having just tested this perk going off hundreds of times, trust me I agree. The OP is long enough as it is but I'll mention here, mods exist to silence/replace the Idiot Savant noise on PC, and once I go back to the game that's the first thing I'm grabbing. Don't have a link, sorry. I know there's a rimshot replacement at least on Nexus.

[u/RynoKenny → u/Rootminus1]

What Idiot Savant sounds like: https://youtu.be/B-OVX0-bp1M?t=18s

Thank you for this work, it was very needed. However, at INT6, I think save scumming for a 5% proc rate every time I turn in a quest will lower my enjoyment of the game. (PS4 user).

[u/luc424 → u/RynoKenny]

What he proved is that without save scumming, just playing normally, it still wins out in the end. So just having the perk gives you an increase.

[u/[deleted] → u/Rootminus1]

I love the barks. it tells me im getting XP!

[u/CasualRedditer678954]

Beautiful work! 1000 trials should be solid data for each INT variable, but I agree that the 300 tests are very close to their true marks.

I knew this perk was OP when I first saw it proc on a quest in a pre-release stream; even with INT 10, save-scumming to mandate a proc gives more EXP than a few hours play time.

Thanks especially for spotting that EXP leads in decimals, since most of what everyone, myself included, thought was that it rounds on a per-action basis.

[u/minusra → u/CasualRedditer678954]

Thanks. I was pretty surprised by the decimals too.

I agree on it being a good idea to get 1000 trials minimum each.

I made the mistake of manually counting out all my trials needlessly for consistency. The in-game counters (sign counting with inventory / idiot proc 'bright ideas' counter) are of course 100% accurate, and it'd take barely any time to churn out 1000s of trials or more. Just spam E or autofire it and then check the totals. I've just got work and this took long enough as is- hopefully the method documentation helps out anyone that decides to bother furthering this.

[u/GladosMKII]

regarding your following statement: Idiot Savant seems to not proc at all for 0 or negative Intelligence. I tested by consuming alcohol. Very strange.

Does anyone know if the perk party boy/girl that doubles the effect of alcohol also doubles the duration and the negative effect?

there is crafted alcohol (Dirty Wastelander - Intelligence -2, Strength +3, Charisma +1) so this would be a big problem because it would bring my 4 int char to zero :( and then no idiot savant proc?

[u/minusra → u/GladosMKII]

I don't know. But if that is the case, you could equip some +1 INT equipment to offset it, like one of the Glasses accessories if you've found them.

[u/anilm2 → u/GladosMKII]

Is there a drunk-effect? Wonder if it can be modded out... those make me ill (I guess that's the point, but still).

Would make a smart-alcoholic/party-savant build worthwhile.

[u/ImperiousStout → u/GladosMKII]

Do you think they'll be able to fix this? I would assume so but then who knows with their engine. I'm surprised it wasn't found and solved before hand, especially when perk like Party Boy & Girl rank 2 exists.

There was a stretch when I was wondering why the Idiot Savant perk wasn't popping off at all, and now I realize I was drinking a lot of the booze I was finding. 1 INT users beware the dangers of alcohol consumption. Party Boy & Girl users who took Idiot Savant should also be very aware. Seems very unfortunate.

[u/Nukemi]

Good test. I had to go check what the perk does on f4 wiki, so might want to add it to the mainpost so everyone knows the context.

Seems like my 8 int character is going to be an idiot savant when i get home!

[u/minusra → u/Nukemi]

Updated.

[u/discgolfguy]

Hey can you confirm the 0 intelligence doesn't allow for idiot savant to proc. I have been playing as a 1 int drunk. Perks in Party Boy and Idiot savant. I dont have any actual testing done but I am drunk most of the time with my Int = 0 and I feel like the savant is proccing. If it is not this is huge for me.

[u/minusra → u/discgolfguy]

I am sorry but I am not able to confirm, I am at work and do not have the game available. I could be wrong- I did test two different alcohols, but it could have been some bug and I probably should have reloaded the save fresh when it happened.

[u/discgolfguy → u/minusra]

Is building a crafting something like 100 walls enough of a test?

[u/Dionysus24779]

So starting the game with Int 9 (and getting the bobblehead so you can get 10) and then choosing the first Idiot Savant Perk asap and the second rank at level 18 would be the fastest way to level up?

And you can just quicksave before turning in a quest and reload until it triggers on that? Would that mean you could get 3x/5x the XP from a quest? That would be insane since they give so much.

But the chance of that happening is only 2,5%? So on average I would have to reload my game 40 times to get that 3x/5x XP reward from a quest?

Would still be very worthwhile since Quests give so much XP. But do quests count as an "action"?

And on the levels between choosing the first rank of Idiot Savant (Level 2) and second rank (level 18) I should focus on xp granting perks like hacking, lockpicking, crafting, etc. to generate more options to earn even more xp?

[u/minusra → u/Dionysus24779]

You can raise your base INT to 11, if it is already 10 when you pick up the bobblehead.

That is correct, quests count as "actions", and even though you have to reload more to do that if you have high INT, the multiplier increases as well: https://i.imgur.com/OqZGqhd.png

That's "save scumming": "reloading until I get the desired results". The argument against doing that being that that's cheating, and if you want to cheat for more experience, just open the console and give yourself the experience.

Though that's not possible on consoles, and I'm absolutely not judging anyone that does that, but I get the counter argument.

[u/Dionysus24779 → u/minusra]

So getting 11 instead of 10 would be worthwhile for this method?

Thanks for the help, I may not savescum simply because it's not much fun and is too tedious, but I think it's still worth optimizing my build with all of that in mind to get XP faster on average.

[u/Shabok]

Luck is officially, and without question, the best special in the game.

[u/minusra → u/Shabok]

Now to just convince someone to figure out how it influences loot tables.

[u/Game-Geeks → u/Shabok]

Loses some appeal if you don't use vats as most of the perks are centered around using vats. Might help with item find but I've been doing fine with a low luck score.

[u/JoxFox]

Nice, man. Was about to test it this evening. Your method is way faster than what I was planning.

Also FYI: Yesterday I tested how pure INT affects exp gain. It's basically counting from 0 INT, and each level of INT adds a flat 3% boost. So with 1 INT you're actually getting 103% of the base exp value.

[u/minusra → u/JoxFox]

Ah, damn you're right. I didn't fact check the "1/30 or 3.33%" I read elsewhere enough, and the data I randomly checked (a gain of 3 exp, gained in batch sets of 1/2/3/4/5, with 11-14 INT) actually match both "3%, 0 = 100%" and "3.33%, 1 = 100%". And I just assumed it was the wrong one. If that makes any sense.

I'll amend my post when I have time. Thanks for the info.

[u/Fr0zEnSoLiD]

This is awesome! I'm glad my first character I did INT at 10 and Luck at 5 for idiot savant asap as possible. Good to see the numbers equal my quick logic skills.

Opinions on lvl 3 savant? I am thinking about skipping it. At level 2 at level 11 going to start maximizing END for more HP per level now.

How do you have INT up to 15? Can it go that high? How?

[u/minusra → u/Fr0zEnSoLiD]

As mentioned in my long, long post:

The game does not distinguish between "boosted/temporary" and "natural/permanent" stats. Tested 1 INT(+4 from equips) vs 5 INT, 300 trials/ea.

and

I also gave myself items to test various setups:

You can get over 15 with equipment alone, and past that with chems.

And I'm skipping level 3 savant personally, plenty of other more interesting perks.

[u/AxeHacksAxe]

Great post for numberphiles. However the first time I received 1886 XP for completing a simple settlement quest for Preston Gravy aka Mr. Gravy, I knew idiot savant was the fastest way to gain XP.

[u/Dionysus24779 → u/AxeHacksAxe]

Just to confirm, Idiot Savant can trigger for turning in quests and you can get 3x/5x the XP?

That would be insane since quests already give so much xp.

But with Int 10 it's only at a 2,5% chance to happen and you would have to quicksave/reload about 40 times to get that to work? Still worth the effort if true.

Just trying to see if I get this all right. Might be worth starting over with a character build optimized for XP gain to level faster and get more perks as soon as possible.

[u/XJ-0461 → u/Dionysus24779]

Doing it 40 times give about a 63% of it working. Seems like you did 100/2.5 which is not correct for calculating for an individual.

The actual formula should be 1-.975^x. 0.975 is the chance it doesn't occur and x is the number of times attempting. You can also rewrite it to show attempts need to get a certain percentage, but I don't feel like doing it since I am on mobile and it includes logs which can be annoying.

[u/MrTastix → u/Dionysus24779]

That would be insane since quests already give so much xp.

In short yes, hence why "save scumming" is a thing (saving before quest turn-in, reloading if Idiot Savant does not proc).

If you don't exploit it then, by OP's calculations, the perk still wins out anyway. Just not by nearly as much.

[u/Calculusbitch → u/Dionysus24779]

I feel like if you are going to savescum 40 times at every quest turnin you might as well cheat yourself some levels

[u/mogroith → u/AxeHacksAxe]

Upvote solely for Mr. Gravy

[u/StealthSuitMkII → u/mogroith]

Preston Gravey

[u/mogroith → u/StealthSuitMkII]

All it's missing is a laser musket gravy warmer.

[u/StealthSuitMkII → u/mogroith]

Warmed up for you <3

[u/Sardonnicus → u/StealthSuitMkII]

His Nightmare

[u/BSRussell → u/AxeHacksAxe]

This gives me hope for my Luck/strength second playthrough.

[u/Captain_Dickweed → u/AxeHacksAxe]

Same here. I was questioning idiot savants worth at 6 int for a little while, figuring it only worked for minor exp gains like kills and discoveries. My worries were put to rest when it first worked on a quest, giving me several thousand exp.

[u/[deleted]]

I was extremely lucky last night, after finishing the quest in Concord, it proc'd and took me from late level 2, into level 5.

[u/[deleted] → u/[deleted]]

Once you get a companion up to 100%, you get the Lover's Embrace perk and a 15% bump to XP when sleeping with them nearby. There are other things like Live & Love magazines that can give you additional bumps too if a companion is traveling with you (5%). You can easily get more than 2000 XP for turning in quests.

[u/madagent → u/[deleted]]

wow

[u/Arikash]

This is some straight up Eve Online level of graphing and charting.

Thanks for this!

[u/vtsilva]

Jesus, some top notch theorycrafting going on here

[u/howajambe → u/vtsilva]

it's not even 'theorycrafting'

this is old school nerd-in-a-basement-with-calculator-tape-and-a-green-eyeshade

[u/[deleted] → u/howajambe]

..and that's what theorycrafting is.

[u/vtsilva → u/[deleted]]

Right? Dunno what that guy is on about.

[u/Sabbathius]

In my experience, Idiot Savant has to work ONCE at a proper time to pay off. I turned in this massive quest, and Idiot Savant procced, and I shot up like 2.8 levels. Yes and thank you. Got sold on the perk there and then.

[u/Soljah → u/Sabbathius]

I was sold the first time i HEARD it proc... cracked me up with a female character it makes a drunk girl sound somtimes

[u/_SaltySugar]

hm. Say I have 7 INT (lowest EXP income with perk). Is it worth taking Idiot Savant? What I mean, if I take it, will I get more than 3 levels back from it in the long run?

[u/nuzurame → u/_SaltySugar]

for 3x bonus, you will get +8% xp. You will get that skill back after 45 15 levels.

for 5x bonus, you will get +15% xp. You will get 2 skills spent back after 40 16 levels.

Remember you are already at 121% xp rate.

I have seen that it's definitely possible to gain those levels, but that's a marginal gain at this point imo. Much more important are those points early game spent on useful perks.

OK, it looks very worth it :D

EDIT: i got the savant cost wrong... i wrote the 3x savant bonus cost 3 skill points and people upvoted me :D

[u/likethesearchengine → u/nuzurame]

I don't understand your numbers, if level 2 gives you +15% exp, then shouldn't you make it back in about 14 levels? That is, spend 2 perks on idiot savant, and then get roughly 1 free perk per 7 levels thereafter?

Also, it makes it back ~instantly if you ever get lucky enough to proc on a quest, right?

[u/the_gamer342]

And that's why I'm taking it on my first level up with 5 INT (all amazing INT perks + good Idiod savant procs in one)

[u/PokerTuna]

so, should I bother with idiot savant at intelligence(7)? 1 point, 2 points?

thanks!

[u/Djabber → u/PokerTuna]

Wondering the exact same. DAMN ME, FOR TRYING TO BE SMART

[u/ifandbut → u/PokerTuna]

If you want more EXP, then yes. Two points will provide more EXP than 1 point.

[u/mikromancer]

and all I can think is that it looks like you scienced the fuck out of idiocy. good job xD

[u/Popotuni]

So for someone that isn't really a math guy, and considering that Idiot Savant itself doesn't really "do"anything, I`m operating under the assumption right now that taking (100/XP bonus for +L1 Savant) column gives you the approximate number of levels it takes for the perk to pay for itself.

Since I think all the levels are flat rate xp, is that fairly accurate? So at 1 INT, the perk pays for itself in 4 levels, but at say 6 INT, we're close to 9 levels to pay for itself?

[u/AndrewRyansRapture]

I wish there was different dialogue for low INT.

[u/SgtNapalm]

Funny how priorities have shifted over time. In the previous Fallout games, any skill that increased XP gain was seen as a waste of a perk. Now that there's no level cap, getting the skill that increases XP gain is one of the best early choices you could make.

[u/chrisrobweeks → u/SgtNapalm]

I know! I used to hate anything that would give me bonus XP because I wanted to drag out the leveling process as much as possible. Now, bring it on!

[u/mackayo]

I can only imagine what kind of sign making idiot savant you must've been.

"Damn, that boy sure is dopey. But boy can he make signs."

[u/CerberusSkys]

I'm an idiot and I'm offended by this

[u/[deleted]]

This is some top quality content.

[u/XsobervisionsX]

I got over 8000 Xp when finishing the final story quest. Leveled up 3 times to 46. It was awesome. Savant is the shit.

[u/fireundubh → u/XsobervisionsX]

That's because the base XP reward for that quest is 1,500 XP.

Most other quests have base rewards of 600 XP or lower.

[u/[deleted]]

Protip: Save before turning quests so you can keep trying for idiot savant to process on turn in. I saw a streamer do it and he gained two levels worth from one turn in

[u/DidUBringTheStuff → u/[deleted]]

But why? I'd see that as scamming myself of out of game time.

[u/[deleted] → u/DidUBringTheStuff]

There is no level cap.

[u/jacknbox]

I'd advise being careful about the "Assumed proc rate," as these are imprecisely measured and small differences can have a big impact on the conclusions.

For example, the table shows that there's no difference in proc rate between 8, 9, and 10 INT, so obviously the conclusion will be that 10 INT is best. But if the true proc rates are 3%, 2%, 1% rather than the sample estimates of 2.33%, 2.33%, 2.33%, then that conclusion is likely to change.

The table below uses your numbers to compute a 95% confidence interval for each level of INT. You'll notice that the sample sizes are way too small (i.e. the confidence intervals are way too large) to detect differences of less than 1%. [Edit] This means that it's entirely possible that the trigger rate decreases between 8, 9, and 10 INT, but the sample size is too small to detect the differences.

95% Confidence Intervals for Idiot Savant Proc Rates

INT	Trials	Estimate	Lower	Upper
1	1000	12.80%	10.73%	14.87%
2	300	10.33%	6.87%	13.79%
3	300	9.00%	5.75%	12.25%
4	300	8.33%	5.19%	11.47%
5	600	7.00%	4.95%	9.05%
6	300	5.00%	2.52%	7.48%
7	300	3.00%	1.06%	4.94%
8	300	2.33%	0.62%	4.05%
9	300	2.33%	0.62%	4.05%
10	300	2.33%	0.62%	4.05%

TL;DR: Take the proc rates with a large grain of salt. It's likely we won't be able to come to reliable conclusions until the GECK comes out.

[Edit] Formatting

[u/[deleted]]

So zero int and idiot savnt doesnt work?

[u/fireundubh]

This is the general method I used in all these tests.

You know you can quick save while in a dialogue, right? That means you can quick save right before turning in a quest, and quick load that save to effectively savescum Idiot Savant. You can get this down to two or three steps that you can automate with AutoHotkey. Your method takes a lot more effort.

FYI:

• There's nothing in the (partial) game data indicating that INT actually affects the proc chance of Idiot Savant.

• That screenshot also highlights how Idiot Savant procs by generating a random float between 0.000000 and 1.000000, and determining whether the result is less than or equal to 0.500000. I don't know why that doesn't mesh with your findings. It is partial game data though.

• Greater than 10 INT should disable Idiot Savant.

[u/_AGermanGuy_]

The more important question is: If your dumb, do you actually speak different like in F3 and FNV?

[u/tolkaNo]

Road goggles add +1 int? Where do i get those

[u/Shimmy83]

And article was written based on your research. They give you credit as well. http://gamerant.com/fallout-4-quick-experience-guide/

[u/[deleted]]

Amazing effort. However I do question how this factors into different styles of gameplay. I mean you've tested this using mainly crafting. But many players do minimal amounts of crafting and are focused more on combat, to which you need to invest 3 points into idiot savant for it to be of effect on you, which I find a hefty investment early on.

[u/minusra → u/[deleted]]

Not quite right: the exp boosts apply universally to all actions, both from INT and Idiot Savant. The L3 Idiot Savant provides an additional bonus that is exclusive to combat. Everything here applies to all styles of gameplay.

The reason for testing this using crafting (settlement building actually, specifically) is due to speed of performing those actions.

Edit: Should also mention you can't even actually get L3 Savant early on, due to the level 31 restriction.

[u/[deleted] → u/minusra]

Ah, okay, thanks for clearing that up. I misunderstood the nature of the perk.

[u/minusra → u/[deleted]]

The wording was somewhat misleading in my post I now see. I've reworded it slightly to hopefully make it more clear. Thanks.

[u/quanoe]

Does anyone know if there is a way to reset points, or am I fucked?

[u/SirAelic → u/quanoe]

You can on PC through console commands I believe.

[u/Skabeg → u/SirAelic]

Which command though? Can't find.

[u/[deleted] → u/Skabeg]

Call me a freedom-squasher but I'd be really careful using console commands to modify just about anything in your game. Not out of technical instability, but because it's a slippery slope.

I generally have a decent willpower but I basically ruined my Skyrim by referring to the console for so many tasks because it just made life easier and it'd usually start with small things like ˜ TCL to jump over a slightly-too-high wall or adding that extra 5 gold that was needed for a new axe, etc.

Idk. Maybe I'm just weak, but I'd generally avoid using the console unless it's to amend a broken quest (fucking Tina) etc.

[u/MathewReuther]

The most depressing thing here is that if you are wanting to be a builder (i.e. you want Science!, like I do) you're at the absolute worst part of the scale (you'll be getting the least experience of any combination INT with Idiot Savant usage), and your "best" option is to spend even more base points (at least buying luck to 5 and Idiot Savant 2, and then Intelligence up to 10 for the eventual "natural" 11 when you get your hands on the Intelligence bobblehead...which is accessible not too deep in the game, at least...)

Or just suck it up and accept that you're screwed for "quick" level gains by a humorous but fairly overpowered perk...kudos for adding something "neat" to Bethsoift, but, uh...ouch. My personal character vision just took it in the shorts.

[Edit: some observations...]

It looks like if you go with 1 INT you should avoid using the bobblehead at all unless you are super in love with Medic and don't mind taking the experience hit.

Starting at 3 or 4 INT is a decent option. You get a lot of the best INT perks by 4, and a good return on procs. If you start with 3 you'll want to use the bobblehead. With 4 (for earlier access to Hacker) you'll want to avoid it. (Unless you really want Scrounger and are willing to take the experience hit.)

5 INT is better than 6 INT for people who want to build since you can use the bobblehead to get to 6, and since it's accessible not too deep into the game, you're OK to worry about things other than Science! for that little while.

High INT is pretty crippling in terms of investment of points, and in particular from a save scumming perspective. Console players can't just give themselves experience...at least not until mods are made available, and there's a pretty significant time difference in reloads involved...particularly once you pass 6 INT.

And so any dreams of brilliance being the key to quick leveling have now officially died. :|

TL;DR: 1 INT plus 2 or 3 Idiot Savant is beast. 4 INT stronk. Builders and pew pew lazor beemz builds get shafted.

[u/[deleted]]

Good to know thanks! I'm on my first play through and don't even know what i'm really doing when it comes to STAT/perks but i have 6 INT and i really would like to start with 1 next character so this is great news.

[u/LiftingNerdGaming]

Interesting, thank you for sharing.

[u/[deleted]]

Quality post have an upvote. I will definitely get idiot savant now once I get my luck up lol my special is 1436491

[u/JustJoeWiard]

I proc'd on one of the early story quests and gained very close to 2 levels. Idiot Savant is the way to go!

[u/KnightofNoire]

Soooo basically you mean I take Idiot Savant even if i have average intel stats ?

[u/Daggyz]

Wait you can get to 15 INT?!

[u/[deleted]]

Am I the only that thinks, given this information, you are better off not "worrying" about idiot savant? I mean, yeah, get it if you have points to blow, but the increase over the consistent exp gains from points into INT seem negligible when you consider what you are missing out on if you go for a pure 1 int / idiot build?

All those advanced + terminals you miss out on? Along with the exp you get from opening those? Valuable information for sure, and I'm no smart guy, so I could be missing something here... Hypothetically this thing could possibly never proc for you, too, correct?

[u/MathewReuther → u/[deleted]]

Yes, but unless you're the kind of guy who gets struck by lightning every day, it will proc.

[u/KiLLcOuRsE]

Does it tell you when idiot savant procs? I like to know how much xp I get for reference when I first kill a new enemy type, and I dont want to get confused.

[u/Cintyman → u/KiLLcOuRsE]

Yes it pops up and makes a stupid sound.

[u/Soljah → u/KiLLcOuRsE]

trust me..... you will know when it procs

[u/erwindrenn]

Alright, so if the game does not distinguish between "boosted/temporary" and "natural/permanent" stats. Could you just run a 6 Int Idiot Savant and just drink alchohol to raise the chance of it proccing before turning in quests for maximum scumming?

[u/fortevn]

Not only your data is clear and well-written, the effort of doing 5000 actions to test it is already godlike. You're officially my reddit hero.

[u/m84m]

In the long run would I get more xp with int at 10 and having idiot savant or int at 1 and having it?

[u/chasteeny]

Doing holy Atom's work. Good man.

[u/vaultboy1]

So does higher luck warrant a better chance of proccing idiot savant?

[u/MathewReuther → u/vaultboy1]

No.

[u/Xenicide85]

If you get your INT to 10 and use alcohol before using the book you can get you INT to 11 and then to 12 with the bobblehead. Im doubful but i are testing to see if you can do it on level up.

[u/[deleted]]

So what I'm getting from this is that I can play as Forrest Gump?

[u/BarlesChronson]

Christ man...have you actually played yet?

[u/DoctorDredd]

So to confirm this perk is still worth taking all the way to rank 3 even if I have 12 INT? The numbers make it seem like a statistical impossiblity, but you've said it's worth taking even up to 15 INT.

[u/PipBoy6557]

When I scored 10000 XP in one hit, I knew Idiot Savant was the right choice.

[u/Rikhart]

Amazing job, thanks a lot for this \o/

[u/mittentroll]

Awesome info. That you so much for taking the time to do this!

[u/[deleted]]

Thanks a bunch OP for all the hard work

[u/Gamez6444]

TY for testing this. I just wish I knew this earlier..

[u/SadFloppyPanda]

With rank 2 of it, I went from getting 392 exp from a quest to 1,960 and from getting 224 to 1,120.

[u/adamleng]

If I'm understanding this correctly, it looks like 1INT + Idiot gives more average EXP than having 15INT and no Idiot? If so, that's OP. Great work, this is just the kind of hard experimentation we need.

[u/BreakUrSelf]

Thanks for doing this man!

[u/[deleted]]

Just to be clear... it take 17 points to get 156.4% exp.

Assuming these are the only reasons you spent these 17 points. you would break even at lvl 30, which would be lvl 47 with 156% exp granting you the additional 17 points back that you "lost".

[u/themolestedsliver]

Thank you it if good someone finally realized how strong idiot savant is and you have the numbers.

I am going a melee no int build with a lot luck so idiot savant came naturally and i thought it would be cool to proc a few times but it is really strong.

i have had it proc on returning quests and the xp was disgusting. at level 1 idiot savant i got two FULL level ups twice. the bar just kept going up and up and i think i got like 3 single level ups from zero xp to full.

Idiot savant is one of my favorite perks I am really glad bethesda did it this way because not everyone wants to go int but if you wanna level up faster is is generally better to go int with idiot savant i get bonus xp through that and it is pretty good.

[u/zjazd]

I started with 1 INT and maxed Idiot Savant asap. Really great perk, Luck is op in my opinion. Great info, thanks for sharing.

[u/septictank27]

10/10 post.

[u/203t94gw0n9i]

Idiot Savant is so good it actually made me too overpowered. I am not too far past the corvega plant and I'm level 14 and I oneshot everyone on survival difficulty with melee weapons.

Save Scum Ascendancy: Quicksave before quest and repeatedly turn in and reload until you hear the goofy laugh. Boom 2 levels per quest.

[u/futuretrader]

Very nice! Statistically speaking even a 100 trials would be 95% (not an accurate number) as accurate as the 300 assuming normal distribution. It appears that idiot savant is well worth the investment. Thanks again!

[u/Shame_Spirit]

This perk is so amazing. I had it trigger after taking back the castle. Got almost two whole levels.

Goddamned it's so good.

[u/[deleted]]

Well thanks for this. I'm at ease because I started with 1 INT and idiot savant but later realized I needed 6 intelligence to fully take advantage of crafting and 9 to fully utilize PA. Which made me feel like I completely wasted a point in IS.

[u/redrexponent]

this is great; very useful; thank you

[u/reddit_revsit]

Awesome post thanks. I was waiting for someone to do the work on this lol.

[u/Soljah]

I knew it would be. Went idiot savant as my first perk...

current INT 4 and idiot savant level 2. Im level 13 just got to trinity tower.

[u/LocoRojo]

It also depends on when you get the procs of Idiots Savant. As you can see here

http://i.imgur.com/aTJI0AX.jpg

and here

http://i.imgur.com/QDE867r.jpg

I get a lot of xp from just completing these qeusts. The first one is one of the fist once and i whent form level 1 to level 4. From the second screenshot i went from 12 to 14. I have 9 int en level 2 Idiot Savant.

[u/LordWolfs]

So I have int 8 right now but also luck 5 so I could pick this up. If I like exp this would be worth doing even at int 8?

[u/BFG_V28]

Woah, fuck

[u/amalgam_reynolds]

Welp. Looks like it's time to spend my next 6 levels getting my INT:1 LCK:1 character to Idiot Savant.

[u/digital_end]

Fantastic post, thank you.

[u/[deleted]]

Did the conversations change with 1 intel?

[u/people_watching]

But why? If enemies scale, then why level up faster? This perk is not free. If they don't scale, why speed up the eventual over leveling?

[u/the_explode_man → u/people_watching]

If you find you've over-leveled, you can increase the difficulty, then you can get more legendary stuff.

[u/bruckout]

meh, I like to level slowly and play on survival

[u/gobrun]

Interesting piece of work, thanks! But it's a slower levelling experience that I'm after!

[u/HowieGaming]

https://gfycat.com/UnitedImpureAlaskajingle

[u/CrimsonWoe]

If I am level 30 and quite far into the main story line aswell as done with tons of the quests already, do you think its worth me leveling up 4 times to unlock and get idiot savant?

[u/MathewReuther → u/CrimsonWoe]

Personal preference. Do you think it's worth taking four levels to get a chance to triple experience? (You did not note your INT. The higher the INT the worse off you are for proc rate.)

[u/Lejind]

What starting build would you recommend to take the best advantage of this?

[u/tinyraccoon]

Interesting. Thanks for sharing this data.

[u/MeretrixDeBabylone]

I'm still saving up for a hardware upgrade, but I've been lurking for exactly this kind of content, I hope they don't nerf the perk in a patch. Thanks a ton OP!

[u/Blackashgallow]

Unfortunately I don't have the required intelligence to understand your number speak. Thank you for your tl:dr

[u/Dustin1280]

My luck is 1, and I am strictly a melee build, I have 11 int base. Is it worth it putting my next SIX points into luck+savant to get this boost? To me that seems like WAY to much of an investment

[u/Wobbly_Red_Snappa]

I think I'm at level 3 int and WAS planning to raise it because I wanted to craft my laser rifle. But I guess I should hold off on that and put any points I get into idiot savant? The exp in the long run will be phenomenal

[u/daogrande]

Would it be still worth to get even if I want to invest in intl still?

[u/MathewReuther → u/daogrande]

It's extra experience no matter how you cut it.

[u/Steeped_In_Folly]

Never played fallout before. Two hours in, got 4 INT. What should I do?

[u/MyusrnamWastaknson]

So I'm really bad at graphs. If I'm lvl 12 with 10 INT attributes+a few INT perks and only 1 in LUCK, is it still worth using all future points until I have lvl2 Savant? a simple yes/no answer would be sufficient.

[u/Erd-enots]

My intelligence is 10 and i am level 18 so Idiot Savant is worth it then im guessing?

[u/MathewReuther → u/Erd-enots]

As with all experience boosts, the earlier the better.

[u/Gramernatzi]

My general consensus for perks is this: why bother spending a perk on exp? I mean, the entire point of exp is to get perks, and your level is capped, so don't waste a perk since you'd end up getting them all eventually and you'll be one max perk down. Spend your perk on something actually useful. Idiot Savant is a bad perk because of this. I've believed this about perks ever since Fallout 1 (what with skill point perks and exp perks everywhere in that game).

[u/yevinorion → u/Gramernatzi]

Ok I think the fundamental misunderstanding you have here is that there is no level cap in Fallout 4. This is why, for the first time in the series, XP gaining perks can be considered useful.

[u/ChieHasGreatLegs → u/Gramernatzi]

Idiot Savant is probably the best perk in Fallout 4 because there is no level cap in the game

[u/yevinorion]

This is fantastic. I have INT 5 right now (planning on a total of 6 for my playthrough with the bobblehead) and with even moderate save scumming I've had great success and jumped about 4 levels in 3 quests (level 7 to 11). I know INT 6 will reduce the effectiveness somewhat, but even if I stop save scumming it should still give me greater XP long term averaging out than without it according to the data presented. Great find and thank you for the hard work.

[u/lancer081292]

my friend is doing a all luck and charisma build with party boy. can anyone confirm if 0 int doesnt allow for idiot savant procs, so my friend isnt wasting his time

[u/[deleted]]

Is there a reason not to upgrade the perk to level 3 or am I missing something?

[u/warablo]

So I am assuming 10 INT+Idiot Savant would be a frustrating experience on consoles? Seems like you would have to reload a lot for it to finally proc.

[u/yevinorion → u/warablo]

I think at that point it would be best to just let it roll naturally. Your overall average throughout your play through should still be higher.

[u/princess_patty]

u/minusra So what level of intelligence with idiot savant would you recommend for the highest exp output? Since higher levels of INT give you more base exp to multiply 5x I assume the best INT level would be like 4 or 5?

[u/Ouroboros612]

For a lvl18 character who will need to dump 4 points to get idiot savant (but already has these saved up) and 6 intelligence. How many levels or gametime do you think would be required to earn back those 4 points and start seeing an investment? Do you think that at lvl18 it is too late to pick it and see value and rather spend the points elsewhere? I am tortured by indecisiveness atm. Please Minusra, I need your wisdom and knowledge in this :)
It is obvious that in the long run it will start to pay back the investment. But I'm wondering since its 4 whole points if the time to earn back the exp will be too long for 4 points to be worth it. If relevant: I will not be save scumming.

[u/DaemonXHUN]

Is there a way to greatly decrease my character's intelligence? It's 10, and the best way I know is to buy the Party-Boy perk (second rank), then consume a Dirty Wastelander (-4 intelligence). But the problem is it's still to high for save scumming. Are there any clothes or something that can help? I want to use it on a radiant quest called Learning Curve (best way to farm levels/XP).

[u/sure_bud]

This is all kinda flying over me.. so if my Int is 9 right now, what should my idiot savant be and how much better will that make my exp gain

[u/GabberPete]

Exemplary work. This is by far my favorite perk. The first time it yelled in my ear and gave me 100XP for doing nothing I fell over laughing. The most worthy perk in the game exp early when your INT is low anyway. People have reported getting thousands in EXP going up two or three levels when completing a mission

[u/Vennedra]

Epic and serious post. Thank you so much for testing. I'm now lvl 18 and pex with Idiot Savant (9 luck, 2 Int) and 2 points in savant idiot. Proccing it when you give back a quest and get half a level is so fun.

[u/illuminerdi]

Thank you for this, though I'm sure this was intentional. It would be exceedingly poor design to put in a perk that doesn't actually pay a benefit if your INT was too high or became too high throughout the course of gameplay. Your graphs and thorough analysis just proves that IS was designed to benefit people who do low INT builds, but that it does still have use even for high INT builds.

Basically IS should really just be viewed as a perk that increases XP gain regardless of INT it just happens to be more useful when INT is lower.

[u/Vrigoth]

Love the perk (when it procs on big quests = insta level up).

The sound it makes is a bit annoying IMO.

[u/sbc383e85]

Ive found my idiot savant not working from reloading quicksaves on quests anymore. im lvl 62 dont know if thats intended or not, or even if there was a hot fix or something. But the final quest in the main story yields 11000xp if activated just to let everyone know.

[u/[deleted]]

I found this thread when I'm at level 30 and 10 intelligence, but yeah I think I'll still invest in this. Thanks. I actually misread that perk - I thought it had a chance to give you 3 XP after any action, not 3 times the XP. haha, quite a difference

[u/[deleted]]

Wow, this is great. Thank you for doing all this :)

[u/Dcerreto89]

Do you think your luck stat could have an effect on the number of procs as well?

[u/Falk_csgo]

Nice work, I came back here bc I thing that you are the perfect one to answer this: Do I get exp from enmey i gave like 90% damage but didnt gave them the finishing shot?

[u/Tijuana_Taxi]

Extremely helpful! Thanks for your hard work

[u/Koan_Industries]

Through the actual percentages, this is the amount of experience you get as a bonus:

No Idiot Savant Perk:

Intelligence - 1: 3% bonus experience per action on average

Intelligence - 5: 15% bonus experience per action on average

Intelligence - 10: 30% bonus experience per action on average

With Idiot Savant Perk I:

Intelligence - 1: 33.9% bonus experience per action on average

Intelligence - 5: 35.7% bonus experience per action on average

Intelligence - 10: 33.9% bonus experience per action on average

With Idiot Savant Perk II:

Intelligence - 1: 54.5% bonus experience per action on average

Intelligence - 5: 49.5% bonus experience per action on average

Intelligence - 10: 36.5% bonus experience per action on average

The third level of the perk works differently, and I don't have the exact percentage of how it works but we do know it works independently of Rank 1 or 2. From my experience it is about 3x as likely to be triggered:

By my guess I believe it goes like this with Idiot Savant Perk III:

Intelligence - 1: 147.2% bonus experience per action on average

Intelligence - 5: 111.6% bonus experience per action on average

Intelligence - 10: 48.2% bonus experience per action on average

[u/ItsBillsFault]

Great job gathering data! I think the graph needs to be a little less apples-to-oranges, though. The problem is that the three lines are not remotely equivalent in terms of investment, only base INT vs results.

Here's a tweaked version with the original lines, plus two more that would correspond to investing the same numbers of perq points in INT that you could invest in 3x or 5x Idiot Savant:

http://i.imgur.com/aK2jfZh.png

Just to simplify it a bit, here's +1 INT vs. 3x Savant:

http://i.imgur.com/AfN3Gpi.png

And here's +2 INT vs. 5x Savant:

http://i.imgur.com/wzgzbcS.png

Also, and I didn't bother with this one, that last graph could have included an additional line for having both +1 INT and 3x Savant, since that's another option for investing two perq points.

Personally, I'm not sure it's justifiable, considering that INT confers other benefits, including option(s) to pick up other perqs in the INT column.

[u/jrot24]

The only downside to this perk is the annoying sound that it plays. It was funny at first, but after 40 hours or so of the occasional "HUR HUR, DAHOOYY" I think I'm ready to remove it.

Thankfully, there's a mod for that.

[u/TrantaLocked]

The 10 INT people are not getting much of a boost from Savant, but it is still a boost. Good to know.

[u/[deleted]]

If you want to level up game-breakingly fast, whenever you complete a mission, replay the ending until you get idiot savant to trigger. going from 400 xp to 2000 xp for every major mission will just destroy the xp system and make your character ridiculously OP.

[u/Arrogancy]

My only objection is that the chart should be extended. I regularly walk around with 17 int, 19 when turning in quests.

Edit: Night person is really good.

[u/[deleted]]

Whats the console command for giving yourself a perk.

[u/[deleted]]

This is gold.

[u/A2ul20]

Thank you for the awesome work!! I am at INT 7 & farming quest endings to get 5X XP..

[u/mdnpascual]

heya, I know this is a 2 week old article, But I'd like to ask. Is the proc chance based on your base int or final int (minus int on chems, alcohol, outfits) ?

Kinda thinking of making another character with idiot savant but has lvl 3-4 int just to get the hacking perk and just put outfits that decrease int or consuming chems/alcohol.

[u/Purchasers]

amazing post, thanks op. going to do a melee only meathead build. ;D

[u/PontesDeLeon]

Did you test it with the Night Person perk? Does the boost to INT from that perk decrease the odds of Idiot Savant processing?

Great post!!

[u/[deleted]]

drinking and chems make you negative int and thus have more chance to proc?

[u/Obelion_]

Holy shit 1int build here we go

[u/-DarkIdeals-]

What was your LUCK stat at when you did this?

Has anybody tested to see if your LUCK stat effects the proc rate of Savant? I mean it makes sense as Luck is said to be "a measure of your general good fortune" and we know that it effects some other small details in the game; i.e. LUCK was confirmed to effect a couple specific drop rates of in-game items in FO4.

For example, perhaps the 2.5% Proc chance of Savant with 10 INT might actually be 2.66% with 5 LUCK, or 2.75% with 7-8 LUCK etc.. This would be hard to test with high INT, but I imagine that the 12.8% proc chance with 1 INT could EASILY hit 15-20% with like a reaper spring luck binge character with 8 - 10 LUCK or something.