I tested Intelligence, Idiot Savant, and experience gain in general

I performed over 5000 actions. Here’s the results.

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

Hopefully I got the formatting right.

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:

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 leveling 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:

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:

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:

• 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.

Original Link – Continuation of discussion