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crow
01-23-2011, 12:36 PM
When your are assigning skill points, what does (Roll) mean? Also I wonder if I have come across a bug. I need one more training point to level up to the next skill level on a skill, the percentage of getting it is 44%. It has missed now 12 or 13 times in a row. If it is 44% then I should have gotten it at least 5 or 6 times, What is going on.

Arkham
01-23-2011, 02:29 PM
You seem you are experiencing the most evil of probablility laws, the Law of Large Numbers. The moral of the story is you have been unlucky. I'm sure Nate has a pretty tested true RNG managing the virtual world.

With that said, your assumption is right. The 'roll' is your 1-100 random number used to determine if you have managed to make your roll needed to increase. Early skills (arond 1-3) are always 100%. Skill/Stat ups around 4 start needing rolls at or under the required %.

Nate
01-24-2011, 02:11 AM
Hi Crow,

Arkham is correct, the value of 'roll" needs to be less than or equal to the percent chance you have to train. The term "roll" is from old school games like Dungeons & Dragons when people used to actually meet at a friend's house for some all day or night face to face gaming where they would "roll" dice to attack and deal damage all the while using their imagination to play and envision what was going on. :)

When dealing with probabilities as Arkham has eluded to nothing is a sure thing except 0% and 100%. If you think of a coin flip it can be heads or tails right? So you have a 50% chance to get either when you flip the coin in the air. It is possible though to get 100 heads in a row even though you have a 50% chance to get tails. It isn't likely to happen, but in theory I could flip a coin for a 1000 years and never get heads. Alternatively i could have a 0.000000001% chance to do do something and succeed on my first try.

So, the Law of Large numbers when dealing with Probability theory states that if you do something enough times the average of the results should be the expected value (44% in your case). Probably a lot more info then you cared to know. ;)

If you would like more details, you can read more on it here if you are interested: http://en.wikipedia.org/wiki/Law_of_large_numbers

Good Luck!

-Nate-

gmarster
01-24-2011, 02:01 PM
I have always looked at LLN from the point of view that the improbable becomes common.

Such as being struck by lightning is a very rare event. With billions of people in the world, there are many people who get struck once, quite a few who get struck twice, etc.

With modern media, the one person that gets struck, say, five times, is found and featured on local news so everyone now "knows a guy" who swears God is out to get him because that can't possibly be random.

Another great LLN story was a stock scam where emails were sent out to millions of people about a well know index. 50% said a stocks would go up, 50% said it would go down. The next day a prediction went out to those who recieved the correct prior "prediction" again 50% saying it would go up, 50% it would go down. After a week, some 10's of thousands of people had recieved 5 correct predictions in 5 days. A lot of people thought that couldn't be "chance" and invested with the firm.

Relevant? Maybe. If a thousand people playing a computer game, someone is going to roll a large number of "fail" in a row. And they can then post about it convinced that it can't be a correct result.

Then again, even with good pseudo random number generators, unintended beat frequencies and initialization quirks can crop up.

Not that Nate hasn't seen *that* before... LOL!