Spam is the biggest threat to organic search engines, whose goal is to provide quality search results for keywords or phrases entered by their users. Google's PageRank algorithm update ("BigDaddy") in February 2006—the final stage of Google's major update ("Jagger") that began in mid-summer 2005—specifically targeted spamdexing with great success. This update thus enabled Google to remove a large amount of mostly computer-generated duplicate content from its index.[33]
At the other end of the spectrum is the small merchant who is only willing or able to work with a handful of affiliates. In this case, the merchant and affiliate may come to an agreement and utilize a “low tech” solution to determine commissions earned (e.g., a custom referral path and an earnings statement powered by Google Analytics). This type of affiliate relationship will typically develop when there is a logical affiliate relationship between two parties, but the merchant isn’t interested in opening up the affiliate program to a wide range of partners via an affiliate network.

As an affiliate for Boatbookings, you will receive 20% of their revenue - effectively meaning your commission will be about 4% of any sales from your referrals.  You also receive 10% of any commissions Boatbookings make on repeat customers who were your referrals. They do have a minimum charter value of 3,000 ($/€/£/etc) before commissions are earned.
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