I take online surveys. For each one I take, I get entered into a sweepstakes. I'm not sure what my odds are, let's just say 1:1000. My question is: do my odds of winning go up with each survey I take, or are my odds always the same, starting over each time?
2006-06-13 18:26:53 · 9 answers · asked by Anonymous in Science & Mathematics ➔ Mathematics
I belong to three sites like this. Does that up the odds?
And once I did get a small sweepstakes check from one. So, they do actually pay off.
I'm not asking if these sites are for real, I'm asking about my probability of winning, strictly out of curiosity.
2006-06-13 18:34:06 · update #1
A good analogy here is flipping a fair coin. So like if you have flipped a coin 5 times and each time came up heads. What is the probability that the 6th time will be heads as well?
Answer: the same as it was the 1st, 2nd, 3rd... 50/50. Each event is independent of every other event, so the probability is always the same for each individual event.
Now, if you flip 6 coins simultaneously, and you want to know what the probability of getting at least one head then you use the Binomial Distribution formula:
b(k;n,p) = (n choose k)(p^k)(1-p)^(n-k)
Where n = the total number of possible outcomes
and k = the amount of desired outcomes
and p = the probability of k occurring
and 1 - p = the probability of k not occurring
Note: "n choose k" is found using the general formula (n!/[(n-k)!k!]
which is like...well say n =5 then n! is 5x4x3x2x1 (in the numerator) and say k = 3 then the denominator is (2x1)(3x2x1).
Is that clear as mud?
2006-06-14 03:22:38 · answer #1 · answered by cb.howell 1 · 6⤊ 1⤋
Your odds of winning each individual survey remain the same no matter how many surveys you have taken before it.
Now, your odds of winning at least one survey of all those you take do increase with the number of surveys, specifically 1-(1-P)^n, where P is the probability of winning any given survey and n is the number of surveys. However, this is calculated before you start taking the surveys. If you have already taken, (and failed to win) 999 surveys, and you asked what your probability of winning the thousandth survey was then, it is 0.001, not 0.632.
2006-06-13 18:39:43 · answer #2 · answered by Pascal 7 · 0⤊ 0⤋
my personal opinion says that u will never win taking those online surveys. theyre rigged just like everything else on the internet. but for probability's sake, yes your odds do go up after many failed attempts... if you look at each one individually... theres always a 1 in 1000 chance. however, if you try 1000 times, probability says u will win once.
2006-06-13 18:31:40 · answer #3 · answered by Anonymous · 0⤊ 0⤋
well depends is it the same survey? the 1:100000 go up every time because there are more people entering so.
at one moment it will be 1:100000 then it will be 2:00043
2006-06-13 18:32:42 · answer #4 · answered by xveritas_et_aequitasx 2 · 0⤊ 0⤋
Those surveys are just a con to get your name, address, telephone number so they can sell you some thing.
2006-06-15 13:34:59 · answer #5 · answered by Anonymous · 0⤊ 0⤋
No, you are not starting over each time...
2006-06-13 18:31:10 · answer #6 · answered by london_calling 2 · 0⤊ 0⤋
You have no probability at all to win
2006-06-14 07:22:49 · answer #7 · answered by Okay 1 · 0⤊ 0⤋
thats what theyd like u to think so u keep playing
2006-06-13 18:32:36 · answer #8 · answered by sball124 3 · 0⤊ 0⤋
no
2006-06-13 18:29:23 · answer #9 · answered by Tasso 1 · 0⤊ 0⤋