It may be a dumb seo questions, but can someone explain this to me?

Selected answers from the Dumb SEO Questions Facebook & G+ community.

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  Carter Lamere: I have an seo question. The other day I was doing Keyword research and came across a website with very low traffic (50-60k visitors per month) that was ranking at #1 in the search engine, while the site below it received 1M + visitors per month. It may be a dumb seo questions, but can someone explain this to me? Thanks!
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  Dave Elliott: Very very debatable weather traffic to a site is a ranking signal or not. Most(including me) say not, but there is high correlation, sites with high traffic are likely to get more shares and have better onsite SEO and are more likely to be linked to etc etc.
  
  Also, how were you getting the traffic figures? Most of the methods are ridiculously inaccurate. ;
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  Shawn Cohen: Agreeing w +Dave Elliott, you could also look at moz page authority to get a feel for how important that individual page is.
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  Carter Lamere: +Dave Elliott
   ;I see, well you learn something new everyday. I looked up the traffic on a website called https://www.compete.com . I was ; always under the impression that higher traffic means increased ranking (and higher page authority).
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  Michael Bird: co-relation and causation is a great concept to get your head around, I too was thinking the likes of SEMrush was super accurate too. Had me very confused at times. :)