alt Hacker NewsAlmost all polls are worthless, because the decision to respond to the poll is itself a major portion of the signal.
It takes extensive work to get around that problem alone, let alone "viral" and other worthless push-polls - work that even the very best in the industry, at the highest level, can make major mistakes on.
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This is totally wrong. Accounting for partisan non-response bias is a standard part of a pollsters job, not some insurmountable gotcha. Some are better than others at this. Polls aren't oracular, nor are they claiming to be. It's almost always better to look at an average of polls rather than a single one.
There is a lot of public data on past elections that anyone can analyze and see exactly how accurate polls have been in the past. If you're expecting polls to be a perfectly accurate prediction then you are misunderstanding their purpose. What they are great at is giving a probabilistic estimate of the outcome, within a certain range.
It's likely that any key race you care about next week will end up within 4 points of the current polling average. It's extremely likely that it will end up within 8 points. That's useful information!
"because the decision to respond to the poll is itself a major portion of the signa"
Yes - they are aware of that.
> Almost all polls are worthless
Do you have one example of a poll that isn't?
Most professional pollers do a good job.
When they are 3 or 4 percentage points off they are ripped to shreds.
The polls for the recent Brazil elections were about 49% for Lula, the result was 52%, that's a 3 point difference, not a massive error margin. With brexit the polling pointed to about 52% for remain, actual result was 48%.
But those are proper polling companies, not worthless online ones.
>Almost all polls are worthless [...] because the decision to respond to the poll is itself a major portion of the signal.
But most polls I see are from professional pollsters like Pew or YouGov? For them, correcting for this is opinion polls 101. That's why you see "representative sample". They're not just randomly polling 1000 people and taking the average. They're adjusting for a bunch of other demographic factors as well.