Are There Too Many Polls?

[JR]

when do polls have enough data to become
statistically relevant?

how many users or votes does it take to make a
conclusion that is meaningful?

[PornoDoggy]

As a liberal, I feel I must speak out against the intolerance becoming rampant on the board. Earlier today it was the Jews ... now the polls ... who will be next?



And the answer to your question, JR, is "6".

[The Other Steve]

Originally posted by PornoDoggy@Feb 25 2003, 12:52 AM

And the answer to your question, JR, is "6".

I thought the correct answer was "it depends on which county in Florida the vote was caste in"

[HoneyBlond]

And the answer to your question, JR, is "6".

Damn and all these years I believed the answer was "42"
and digital watches were a pretty neat idea

[Vick]

Originally posted by HoneyBlond@Feb 25 2003, 04:25 AM
Damn and all these years I believed the answer was "42"
and digital watches were a pretty neat idea

Don't Panic

[JR]

but i lost my towel!

[Almighty Colin]

Originally posted by JR@Feb 25 2003, 01:37 AM
when do polls have enough data to become
statistically relevant?

how many users or votes does it take to make a
conclusion that is meaningful?

Depends on what one means by "statistically relevant".

If there were just two choices, results would be correct to within 3% after 1000 people voted. It goes as the square root of the number of people questioned. The square root of 1000 is 31. 31/1000 is about 3%. 100 people sampled is a 10% error.

Interestingly, the percentage of the population in question that is polled is not significant. Polling 1000 completely random people out of a population of 250 million is a better measure of the results one would obtain by polling all 250 million people than a poll of 100 people out of a population of 1000 would be.

----------------
A little more in-depth discussion if interested. The 3% number above is the standard deviation. 67% of a population in a normal distribution falls within one standard deviation of the mean.

This means that if we poll 1000 completely random people as to who they will vote for president, there is a 67% chance that will be accurate to within 3% if we had polled ALL of the population.

95% of a population falls within two standard deviations of the mean. So if we poll 1000 completely random people as to who they will vote for president, there is a 95% chance that will be accurate to within 6% if we had polled ALL of the population.

It's important to note that distinction. When we see polls on television or in the newspaper that say "Error +/- 3%", it doesn't mean that if we had polled everyone it WOULD be correct to within 3%, it only means that it will be that accurate 67% of the time.

3 standard deviations is 99.7%. So if on election night, a poll of 1000 says a candidate has 59% of the votes, there is a 99.7% chance that candidate will win .. and a 3 in 1000 chance the trailing candidate will pull it out.

[Vick]

See you at Milliways

So long and thanks for all the fish