Very easy: double the visits to halve the ranking.
I just blogged at upnaira.blogspot.com about finding the connection, and how rewarding to end up with such a neat graph:
|Relationship between Alexa rank and monthly visitors|
|Site||%Traffic Reach||Est. Monthly Visitors*||Alexa rank|
*The monthly visitors numbers are estimated by assuming jobberman has 1million visitors per month (I think that corresponds to a ranking around 5k) and that the traffic reach percentage (data given by alexa for each site) is simply number of visitors for this site / a fixed number corresponding to all traffic. That is, take the traffic to be proportional to the traffic reach percentage.
Well, who wants to do this experiment on a large scale?
Plot Global rank against Traffic-reach % or Traffic-Reach-estimate-of-Monthly-Visitors and see how well the data fit this law.
Alexa.com ranks at least 10million sites, so you could test with that many datapoints.
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