The section will be fairly short, but I thought it would be good if I explain in a little more detail each derived statistics, which attribute affects it, and what it does. First off derived statistics are set values that are determined by the number of points you have in that related attribute and any perks you have, among other things, that affect that statistic. Let's take carrying weight, for example. Let's say you started the game with 6 points in strength and therefore can carry 210 pounds. You then level up to level 8 and pick the Strong Back Perk and you can now carry 260 pounds. That affect is permanent. Then you eat a Bighorner Steak and your strength increases by 3 points and so now you can carry 290 pounds. However, this bonus won't last forever, and once the steak wears off, your max carrying weight will return to 260. The Bighorner steak is a temporary derived statistic modifier. That should give you an idea on how derived statistics work, so without any more delaying, here's all the derived statistics:

**Derived Statistics**

**Action Points**
Description: Action Points are required to do anything in VATS. For example, firing a .357 magnum revolver requires 20 AP. Therefore, if you don't have at least 20 points of AP left then you can't fire the revolver in VATS. AP regenerates over time, and it takes 16.66 seconds to recover the AP bar to full, regardless if you have 95 AP or 80 AP. However, this doesn't include perks you receive that increase your AP, meaning that if you have 2 ranks in the Action Boy/Girl perk it will actually take over 23 seconds to raise your AP bar to full. The perk Nerves of Steel decreases the base regeneration rate to 13.33 seconds. The base value of Action Points is 65 and the formula for the amount of AP you have is: Initial Level=65+(3xAgility)+Modifiers(Perks, clothing etc.) For example, if you start out with 10 Agility and get two levels in the Action Boy/Girl perk, your total AP would be found like this: 65+(3x10)=95+30(from Action Boy/Girl)=115 AP. The formula for AP regeneration is: (1/.060=16.66 seconds)
Attribute that affects it: Agility
Action Points Gained Per Point in Agility:3
Permanent Modifiers: Math Wrath(Perk, -10% AP costs),Plasma Spaz(Perk,-10% AP costs for plasma weapons), Action Boy/Girl(Perk,+15 AP per rank), and Kamikaze(Trait,+10 AP).
Temporary Modifiers: General Oliver's Uniform(+20 AP when equipped), Nuka Cola Victory(+30 AP when consumed, lasts 1 hour), Rocket(+30 AP when consumed, lasts 1 hour), Dixon's Jet(+10 AP when consumed, lasts 1 hour), Jet(+15 AP when consumed, lasts 1 hour), Ultra Jet(+40 AP when consumed, lasts one hour), Trail Mix(+6 AP when consumed,(must check duration)), Mushroom Cloud(+7 AP when consumed,(must check duration)), 400 Rads of Radiation(AP-2 until cured), 600 Rads of Radiation(AP-4 until cured), 800 Rads of Radiation(-4 until cured.) Note that the Radiation affects are cumulative, meaning that if you have 600 Rads of Radiation that you actually have AP-6 until cured.
Special Cases: Nerves of Steel, which the time it takes to bring your AP bar to full by 20%, and Grim Reaper's Sprint, which restores 20 AP every time you kill something in VATS.
Maximum Permanent AP:115 with 10 Agility and 2 ranks in the Action Boy/Girl perk.
Maximum Temporary AP:Around 218 AP if the player has 115 permanent AP, wears General Oliver's Uniform and cosumes a Nuka Cola Victory, Ultra Jet, Trail Mix, and Mushroom Cloud. I'll have to check if the different forms of Jet stack, such as taking Ultra Jet with Rocket.

**Carrying Weight**
Description: Carrying weight is the total amount of weight you can carry before becoming over-encumbered. Almost all items weight something, and if all those item's weights start to add up as long as you keep them in your personal inventory. Eventually you will become over-encumbered if you do not drop some of those items at your house, which is why it's a good reason to get a house early on at, say, Novac. When you're over-encumbered you can not run or fast travel(unless you have the Long Haul perk.) You'll want to drop your stuff off or sell it after every location you fully explore. Anyway, back to carrying weight. The formula for carrying weight is: 150+(Strengthx10)+Modifiers(such as Strong Back)=Carrying Weight. For example, if the player has 10 strength and the Strong Back perk, this is how you would find his carrying weight: 150+(10x10)+50=300 lbs
Attribute that affects it: Strength
Max Carrying Weight Gained Per Point in Strength:10 lbs
Permanent Modifiers: Strong Back(Perk, +50 lbs max carrying weight)
Temporary Modifiers: Whole bunch of food and alcohol(+specified number to Strength), whole bunch of uncooked food in Hardcore Mode(-specified number to Strength), Buffout(+2 Strength), Ant Nectar(+4 Strength), 600 Rads of Radiation(-1 Strength), 800 Rads of Radiation(-2 Strength), Buffout and Steady withdrawal(-10 Strength), and Nectar withdrawal(-2 Strength.)
Special Cases: Pack Rat(Perk, items less than 2 lbs weigh half as much) and Long Haul(Perk, can fast travel when over-encumbered.)
Maximum Permanent Carrying Weight: 300 lbs
Maximum Temporary Carrying Weight: 300 lbs

**Critical Chance**
Description: When you score a critical hit you do extra damage. See the Luck part of the Attributes section for a little more detail.
Attribute that affects it: Luck
Percent Gained in Critical Chance Per Luck Point: 1%
Permanent Modifiers: Built to Destroy(Trait, +3%), Finesse(Perk, +5%), Ninja(Perk, +15% with unarmed and melee weapons), Laser Commander(Perk, +10% with laser weapons), and Set Lasers to Fun(Challenge Perk, +2%/4% with lasers.)
Temporary Modifiers: 1st Recon Beret(+5% while equipped), Naughty Nightwear(+1 Luck while equipped), True Police Stories(Magazine,+5%(+10% with the Comprehension perk), VATS(+5 critical chance while using VATS), individual weapon modifiers(+ specified %), and Lucky Shades(+1 Luck.)
Maximum Permanent Critical Chance: Without taking individual weapon modifiers into account, 33% melee and unarmed weapons and 32% for Laser Weapons. All other weapons: 18%
Maximum Temporary Critical Chance: Without taking individual weapon modifiers into account, 48% without VATS, 53% with for melee and unarmed weapons and 47% without VATS and 52% with for laser weapons. 33% without VATS and 38% with for all other weapons.

**Damage Threshold**
Description: Damage Threshold(or DT, as you will see it in game) is a value that determines how much damage is subtracted from the total you receive. In other words if you have a DT of 10 and are hit with an attack that does 20 damage than only 10 points in damage will actually affect your character. However, no armor is completely bullet proof, meaning if you're wearing Remnants Power Armor and you're attacked with a 9mm pistol it'll do at least it's minimum damage, which is 20% of the regular damage. The combination of the armor's DT and DR determines the damage reduction, however, as mentioned, at least 20% of the regular damage hit the player. The formula for determining the damage reduction is: max((Shot Damage-DT)x(100%-DR%),(Shot Damagex20%)=Damage Inflicted. It's kinda of complicated, but the game has a good way of showing if you and your enemies hits are doing good damage or minimum damage. Damage which is reduced to minimum value is indicated by a red shield on your enemies health bar if your the one attacking, and a red shield on your health bar if the enemy is attacking. A broken red shield by the enemies health bar indicates you over came all of the enemies DT and DR(unless there DT is at 0 already.) The base value for DT is 0, modified by apparel, perks, consumables, traits, and ammunition.
Attribute that affects it: None
Permanent Modifiers: Toughness 1/2(Perk,+3% DT with rank 1, +6% DT with rank 2), Nerd Rage!(Perk, +15% DT when health reaches 20% or lower), Stone Wall(Perk,+5% DT against melee and unarmed weapons), Hit the Deck(Perk, +50% DT against all explosives), Sub Dermal Armor(Implant, +4 DT), Whiskey Rose(Companion Perk, raises DT from 2-6, depending on the player's survival skill, when consuming whiskey, and Kamikaze(-2 DT.)
Temporary Modifiers: Almost all apparel(+specified number), Nuka-Cola Quartz(+6% DT), and Whiskey(+6% DT)

**Damage Resistance**
Description: The other part in the damage reduction equation that determines the total damage you take. It is known as DR in game. DR is calculated after DT and it's almost like it was removed as far as the main character is concerned. The maximum DR the game considers in equations is 85%. Anything higher the game ignores.
Attribute that affects it: None
Permanent modifiers: None
Temporary modifiers: Med-X(+25 DR when consumed), Slasher(+25 DR when consumed), Rebreather(+3 DR when equipped), and the Trenchcoat(+5 DR, although this item is flagged non-playable so it cannot be equipped.)
Max Temporary DR: +53 DR

**Fatigue**
Description: Fatigue is nonfatal damage. If your fatigue reaches below 0 it will automatically lower to -30 and your character will go unconscious. Fatigue restores at the rate of +1 fatigue point per second until it is at maximum. For NPCs, the range of fatigue is 50(for creatures such as mole rats) to 760(Legate Lanius.) The value is modified by endurance and level, but each NPC has a base level. The formula for fatigue is: Fatigue=Base Fatigue x(1+(Endurance x 0.2)+(Level x 0.1).
Attribute that affects it: Endurance
Permanent Modifiers: Level(explained above)
Temporary: Boxing Gloves(-35 Fatigue per hit), Boxing Tape(-20 Fatigue per hit), Golden Gloves(-50 Fatigue per hit), Cattle Prod(-50 Fatigue per hit), and Bean Bag(Ammunition for 12 gauge shot guns, -250 Fatigue per hit.)

**Hit Points**
Description: Also known as HP in pretty much every game. Determines how much damage you can take before your character dies and you have to reload an old save. The formula for your total hit points is: 95+(Endurance x 20)+(Level x 5)+modifiers(such as the Life Giver perk)=Total HP. Here's an example for a player who starts out with 10 Endurance and has the Life Giver Perk and is level 30: 95+(10x20)+(30x5)+30=475. A heart beat sound effect can be heard once your health starts to reach dangerous levels. As your health gets lower the sound gets faster.
Attribute that affects it: Endurance
Permanent Modifiers: Life Giver(Perk, +30 HP)
Temporary Modifiers: Buffout(Maximum HP +60 and +4 in Endurance when consumed.)
Maximum Permanent HP: 475
Maximum Temporary HP: 535

**Poison Resistance**
Description: Determines how much poison damage you take. If you have 45% poison resistance you take that much less poison damage. The formula for poison resistance is: (Endurance-1)x5+modifiers=% of resistance. For example if you have an endurance of 6 and ate Spore Plant Pods, the formula would be:(6-1)x5+75%=100%. Some of the hardest enemies, such as Cazadors, have a very high poison damage so 100% poison resistance can be quite useful if used properly.
Attribute that affects it: Endurance
Permanent Modifiers: None
Temporary Modifiers: Spore Plant Pods(+75% Poison resistance) and Antivenom(Cures animal poison
Maximum Permanent Poison Resistance: 45%
Maximum Temporary Poison Resistance: Technically 120% although only 100% of it matters

**Radiation Resistance**
Description: Rad Resistance determines how much radiation you'll resist when you receive radiation. Radiation will be discussed in its own section. For now all you need to know is the formula for radiation resistance is:(Endurance-1)x2+modifiers=total radiation resistance. For example, if your character had 10 points in Endurance and is wearing a radiation suite the formula would be: (10-1)x2+40=58% radiation resistance. I'm not exactly sure if there is a limit in the maximum radiation resistance, but in Fallout 3 it was 85%, in Fallout 1 it was 100%, and in the rest it's 95%. Out of those it's probably the same as Fallout 3.
Attribute that affects it: Endurance
Permanent Modifiers: Rad Resistance(Perk, +25% Rad Res.) and Rad Absorption(Radiation-1 every 20s if not gaining Rads.)
Temporary Modifiers: Rad-x(+75% radiation resistance when consumed with 100 Medicine), T-45d Power Armor(+10% Rad resistance when equipped), T-51b Power Armor(+25% Rad resistance when equipped), T-51B Power Armor Helmet(+8% Rad resistance when equipped), Remnants Power Armor(+15% Rad resistance when equipped), Remnants Power Armor Helmet(+5% Rad resistance when equipped), Radiation Suite(+30% Rad resistance when equipped), and Advanced Radiation Suit(+40% Rad resistance when equipped.)
Special Cases: RadAway(-180 Rads at 100 Medicine and with the Free Radical perk), Free Radical(RadAway does 3x its normal effects), and Rad Child(Radiation=HP regeneration.)
Maximum Permanent Radiation Resistance: 43%
Maximum Temporary Radiation Resistance:Technically 158% although only somewhere between 85% to 100% of it matters.

**Skill Points Gained Per Level**
Description: Pretty much the most important derived statistic to maximize so what time better than now to explain how to do just that. You use skill points to improve skill(pretty obvious I suppose, but this is a complete guide so...) and the formula for the amount of skill points you gain per level is: (Intelligence/2)+10+Modifiers=Skill Points Gained Per Level. In other words if you have an intelligence of 10 and the Educated perk the formula is:(10/2)+10+2=17 Skill Points Per Level. That's good, but if you want to find how many skill points you gain in total the formula is a little different. If you get the Educated Perk at level 4 the formula goes like this:(10/2+10)x4=60 points. Okay, now do the formula for the Educated perk x 26 which is:(10/2+10+2)x26=442. Now add those two together and you get 502, the maximum number of skill points you can allocate. However, were not done yet. There's a thing called skill books that raise your skills by 3 without the Comprehension perk and 4 with the Comprehension perk. There are 52 skill books in the game and almost all skills have 4 books. The exceptions are the Repair skill, which has 3, and the Science skill, which has 5. If you don't have the Comprehension perk that's 156 extra skill points, or 658 maximum skill points. If you have the Comprehension perk it's 208 skill points, or 710 maximum. Quite a difference, huh? If you plan to get the Comprehension perk(which you should), don't read any skill books to maximize the value of the perk, and you also shouldn't read any skill books until you have gotten that skill at the max level you want to raise it to, such as 60 with the Science skill since 20 points can be gained from reading books and 80 is the maximum you want because you can just read skill magazine to use those few very hard terminals. If you do plan to read before hand, **make sure you write down the books you read so you don't screw up! ** Any back to calculating how many skill points you have. Okay, so were at 710 and 1,300 is the total skill points it would take to max every skill, so right now were at about 50 for every skill. Not that good but there is one other thing I forgot to mention: Your base skill level. Those skill modifiers in the attributes add up and if you went with my attribute picks in the attributes section of the guide than your base skill points should add up to 243. That's 843 total skill points...but don't worry there's still one more thing to add: Tagged skills. That adds an extra 45 skill points with a total now at 888. That's enough to get all your skills to 68. Still not that good so you're going to have to choose a few skills to ignore. Which ones to ignore will be discussed in the skills section.
Attribute that affects it: Intelligence
Permanent Modifiers: Educated(+2 skill points every level) and Comprehension(+4 skill points when reading books and double the normal value when reading skill magazines.)
Temporary Modifiers: Seeing as attributes affect the total number of skill points, any item that raises an attribute. I discussed at the end how to temporarily(basically for 1 minute) raise all your attributes to 10 so that's like 325 total base skill points, which brings the total to 1035, which is very, very good, although it only lasts for one minute. Skill magazines also boost skills by +10(+20 with the comprehension perk), so that's around 1,295, which almost maxes out every skill, but again this period is so short that you'll only experience this perfect character for a short amount of time.
Maximum Permanent Skill Points: Around 888
Maximum Temporary Skill Points: Around 1,295

**Unarmed Damage**
Description: Determines the base damage of all unarmed attacks. The formula for base unarmed damage is: Strength/2=Unarmed Damage. For example, with a strength of 10 your unarmed damage is found with this formula: 10/2=5. This base damage is added on to the damage an unarmed weapon deals.
Permanent Modifiers: Anything that increases Strength permanently.
Temporary Modifiers: Anything that increases Strength temporarily.
Maximum Permanent Base Unarmed Damage: 5
Maximum Temporary Base Unarmed Damage: 5

Final notes on derived statistics: The order of usefulness out of those is this (from best to worst):Skill Points Gained Per Level, Maximum Hit Points, Critical Chance, Damage Threshold/Damage Resistance, Poison Resistance, Action Points, Carrying Weight,Fatigue, Radiation Resistance, and Unarmed Damage. Some people may find it weird that I put Poison Resistance higher than Action Points and Carrying weight. The reason why is you can get a house early on in Novac and the containers in your house can hold a limitless number of items. Then you've got companions who make Carrying Weight even less useful. Since I play lots of First Person Shooters, and since Fallout New Vegas has iron sights, I find Action Points less useful, although I could understand why you'd like them a lot so that one is just personal preference. I like Poison Resistance a lot because the hard enemies like Cazadors and Giant Rad Scorpions do a ton of poison damage so having 100% poison resistance, even temporarily, is quite useful. Skill points should be obvious, as with HP. I like having a high critical chance because there's something satisfying in reading the message on the screen that I got a critical hit, not to mention how useful it is. DT and DR are very important because when you're fighting a difficult enemy on very hard you're going to want to block out all the damage you can. Fatigue is useful in some situations, like against a Death Claw, but it doesn't have the overall usefulness of the other derived statistics. Radiation Resistance can be raised easily and is only needed in certain occasions, and +5 max base unarmed damage is puny, so even if you used unarmed weapons only it's not that useful. Anyway, a final thing a should note is that there is one more statistic: Speed. It's such a small derived attribute that I didn't give it a section, and besides that I don't have enough information on it. However, I do know a few things that will increase/decrease your speed. 1.The higher your Agility the faster you run. 2.Holstering your weapon if it's two-handed makes you run faster. There is no difference with one-handed weapons. 3.You run faster in Light Armor than Heavy Armor and even faster with no armor on at all. You can fin if an item is Heavy/Light Armor in its statistic thing in the PitBoy. 4.You're not over-encumbered. If you're encumbered you can't run making this the biggest burden on your speed.