Margin of error demystified

There's a lot of nonsense on social media, especially in relation to polls, and even more in relation to the margin of error – some people seem to have made it their method of choice for dismissing inconvenient poll moves. But it does serve a serious purpose – to quantify uncertainty in sample-based estimates due to random statistical variation.
There are, of course, plenty of non-random sources of error in polls, and I've looked at some of them in my margin-of-error explainer for CapX.
Of course, this is a heavily simplified version of reality. I didn’t talk about differences depending on levels of party support, the effects of stratification, weighting, don’t knows, turnout adjustments, correlations in a multi-party system or asymmetric margins of error near the arithmetic bounds, but you get the picture.

Get it before it’s on the website – sign up for this briefing: <style type="text/css"
#mc_embed_signup{background:#eeeeee; clear:left; font:14px Helvetica,Arial,sans-serif; }
/* Add your own MailChimp form style overrides in your site stylesheet or in this style block.
We recommend moving this block and the preceding CSS link to the HEAD of your HTML file. */

Please send me (select as required):

Email Format

About The Author

Related Posts