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Raffle! Win Big Prizes! (And help fund LPF!)

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@Niko
twhite828 did the calculations perfectly. Unless someone has some reason we have completely overlooked that his calculations are not correct, there is more than 99.9% chance that I would win at least one of the first 60 prizes.
Here's the chances of not being chosen
The 0.0919% number is utterly incorrect. You can't just multiply the results like that. To calculate a range of values you need to use a distribution and a range.

You're worrying too much on the fact that you had 40 tickets, but the total of tickets was, as I said up there, 389. That's 349 tickets that are NOT yours. No need for complicated math to see that 349 tickets could have been drawn before your 40 tickets came in, even if it was randomly.


EDIT: Dude, I'm not trying to shut you off, but I'm actually studying this right now (I have all the papers lying on my desk if you want me to take a picture of the mess :p). But that's the way it works...
 
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jayrob

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Thanks Dave! (and Glenn)

I have sent PM's to both of the persons who have won my donations...

* Tmar - 18650 Kit
* Nemo2423 - Pocket Mini Kit

Just get back to me with your shipping addresses! :)
 
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daguin

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@Niko
twhite828 did the calculations perfectly. Unless someone has some reason we have completely overlooked that his calculations are not correct, there is more than 99.9% chance that I would win at least one of the first 60 prizes.
So the .1% expressed itself admirably, I think. (I don't even care if the math is correct or not)

.1% is NOT 0%


MATH -- It's everywhere . . . . . .

Peace,
dave
 
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Krutz

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OH! MY! GOD! woooooooaaa!
thats the first time ever I win some main price! *dances around* awesome! :)
*speechless*

i'll put that WL laser to good use! ..or at least much use, that is :)

manuel
 

Trevor

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I'm sorry, where did you get that number from?
Say you have three 10% chances in a row. Winning any *one* of them is a 10% chance. Winning *any* two of them turns into a 1% chance, because it's multiplicative. Winning *the first two* is also a 1% chance because those are "any two," they just happen to be the first two. I based my calculations on this premise. I have not taken statistics. Correct me if I'm wrong, this math intrigues me. :)

I used Excel for this. My first column was the drawing number. The second was 40/(394 - X), X being the number of tickets already drawn. X started at zero, obviously. The third column was the probability *not* to win - one minus the second column.

The fourth column was the chance to lose all of the previous drawings, up to and including the current one. Based on the premise I first mentioned, all of them were multiplied together to yield my stated number - the the chance for all of those successive probabilities to come true.

However, it's a nonzero probability. Meaning that it is possible. Sith may be unlikely, but Sith happens. As Dave said, that nonzero chance seems to have expressed itself quite admirably indeed.

-Trevor
 
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OH! MY! GOD! woooooooaaa!
thats the first time ever I win some main price! *dances around* awesome! :)
*speechless*

i'll put that WL laser to good use! ..or at least much use, that is :)

manuel
Congrats Krutz, you are finally here :p Some good luck here, well you had chances, with 10 tickets :D
 
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Say you have three 10% chances in a row. Winning any *one* of them is a 10% chance. Winning *any* two of them turns into a 1% chance, because it's multiplicative. Winning *the first two* is also a 1% chance because those are "any two," they just happen to be the first two. I based my calculations on this premise. I have not taken statistics. Correct me if I'm wrong, this math intrigues me. :)

I used Excel for this. My first column was the drawing number. The second was 40/(394 - X), X being the number of tickets already drawn. X started at zero, obviously. The third column was the probability *not* to win - one minus the second column.

The fourth column was the chance to lose all of the previous drawings, up to and including the current one. Based on the premise I first mentioned, all of them were multiplied together to yield my stated number - the the chance for all of those successive probabilities to come true.

However, it's a nonzero probability. Meaning that it is possible. Sith may be unlikely, but Sith happens. As Dave said, that nonzero chance seems to have expressed itself quite admirably indeed.

-Trevor
The calculation is incorrect. This is a raffle, where drawn tickets are thrown away. You need to use a hypergeometric model (should be called like that in English :p) where the combinatory number appears.
Then you go to special distributions where you need to get the median and standard deviation (or variance) (sorry if some terms are incorrect, I didn't study this subject in English yet) and use a full sum to get the final answer.

If you want to learn about this then please use Wikipedia, because I'm studying this right now and I can't calculate results for the raffle anymore, I need to go back to studying. If you REALLY want to learn probability calculations send me a PM on January and I'll teach you :)
 

daguin

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Could we please just wait for Glenn to reply to this? He must be able to check or remember if he did in fact put in 40 tickets for me.. I'm sure it was hell to go through to cut all those out.

I'm not looking to spoil the fun and I do not want the raffle redone, I just think that, even being a non-zero possibility, 0.0919% is still so tiny a number that a simple human mistake is far more likely. I mean, who'd have expected some jackass to buy 40 tickets anyway?
Glenn -- Don't let him "guilt" you into doing something . . . . .

Peace,
dave
 
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Didnt think it would end like this..:undecided: No matter how you calculate, 40 tickets does not guarantee you winning anything. I dont see the problem here. We offered to give you something, but somehow its not enough. You lost buddy, it's a fact if you like or not.
 
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Woohoo! I was secretly wishing to get one of them LPMs... I will be metering those photons real time!!! Million thanks to Glenn for all his hard work and to Laserbee for the great prize!!!
- Awesomeness!
- Robert
 
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I regret to inform you that I learned how to calculate probability 3 years ago, and got 98% on my exam.. As far as I can see none of the variables you have mentioned are valid for this calculation and twhite was completely correct. Maybe it's because I am stressed at the moment and cannot do maths at all any more, but I cannot see anything wrong in what he calculated.

@Dave
Seriously.. do you think I would try to con Glenn out of anything? I just want to know it was a mistake or if I really did hit that 0.0919%. If Glenn still has the tickets he should be able to quickly check if there are 4 or 40 tickets for me there.. that is all I am asking for.

Seb
As I originally said in my first post regarding this subject, there could be a mistake in my calculations. Again, I'm still studying this and not everything's clear yet.
 

Trevor

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The calculation is incorrect. This is a raffle, where drawn tickets are thrown away. You need to use a hypergeometric model (should be called like that in English :p) where the combinatory number appears.
Then you go to special distributions where you need to get the median and standard deviation (or variance) (sorry if some terms are incorrect, I didn't study this subject in English yet) and use a full sum to get the final answer.

If you want to learn about this then please use Wikipedia, because I'm studying this right now and I can't calculate results for the raffle anymore, I need to go back to studying. If you REALLY want to learn probability calculations send me a PM on January and I'll teach you :)
Ahh. I'll defer to your formal background and poke around on Wikipedia.

Just out of curiosity, what would you consider the likelihood of two occurrences, each with a probability of 10%, occurring in a row? I'd always assumed it was 1%, because I thought concrete percent chances (I mean like a die) were multiplicative. It makes sense that way when I think about it.

-Trevor
 
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Just wondering but who do i need to send my information to
f22warzone 44 SF-AW210 red diode Donor anonymous
 

Dusty

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Dusty 12 selection of loose optics, (lenses, filters & diffraction gratings, etc), Donated by Jack

Dusty 33 Blu-ray Blocking Goggles Donated by Glenn, (scopeguy20

:san::san:

Very pleased... Thanks Glenn for organising this raffle, it was a great idea...:thanks: :gj:
 

daguin

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@Dave
Seriously.. do you think I would try to con Glenn out of anything? I just want to know it was a mistake or if I really did hit that 0.0919%. If Glenn still has the tickets he should be able to quickly check if there are 4 or 40 tickets for me there.. that is all I am asking for.

Seb

You guys make it sound like I think I deserve all the main prizes or something..
It has nothing to do with you.

You do not know Glenn like I do. He is probably the nicest man I have ever met. When he sees your stress over this, he is going to want to do something to help relieve it.

WE are not making it sound like anything. You are making it sound like Glenn must have screwed it up in order for you not to have won something. You believe you SHOULD HAVE won something. That's not how raffles work.

You COULD HAVE bought 100 out of 165 tickets and still have lost. Yes. It is possible that your 100 tickets could all be the ones left in the bowl after the 65 tickets were drawn.

It might suck to be you right now . . . . but you are still you

Peace,
dave
 




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