This is something I am not decided on. Do affiliate links that are dofollow affect search engine rankings for your page? If not, then why do article directory services like Ezine not allow affiliate links in your articles? What about nofollow? Can that negatively affect search engine rankings?
As far as I know, "no", affiliate links don't affect search rankings. As far as Google is considered, a Clickbank affiliate link is the same as any other dofollow outbound link. Ezine doesn't allow affiliate links because they think it makes an article look spammy.
^ Agreed with dlm, just take a look around peoples landing pages and blogs on here or on the WF and you will see a lot of pages built entirely around clickbank affiliate programs and they manage to get ranked in google fine (if the person knows what they are doing). As dlm said Ezines don't allow it simply as it lowers the quality - they would get 1000s more people submitting poor quality articles - this just raises the standard a little
Why not just do a php redirect to be safe> Plus, you can cloak your traffic too. Check out tracking202.
Yes, I don't think it matters too much I think as dlm says the main reason Ezine articles does not accept affiliate links is so you have to spend a bit more time getting a landing page in place - which in turn gives more content for their site. Or at the very least you have to purchase a domain and forward it to your affiliate link. Also i think if you are using an anchor link as long as the actual site you are linking too is not spammy it should be fine.
This may not be as plain as you guys are saying here! Most SEO gurus (even some I trust) usually recommend that people reduce the number of affiliate links on their sites when they loose or go down on their rankings. However, I have so many websites filled with affiliate links, and have ranked first positions on very competitive keywords. Google ranking is affected by 200 or more signals!!! Your inbound links are just one of them. So if it affected rankings, it wont be that much anyways. We are talking about a (1/200) or a 0.005, everything being equal. But the various signals are not equally weighted though.
If you are scared that an affiliate link would lower your on page seo than make the link domain.com/affiliate.php and make it a no follow. This will make the search engine think its just another page on ur site and, if they follow the no follow rule, won't follow it. Even though no follow is only for indexing SEs that are meant to follow that rule may check out whats on the other side of the link just in case. Personally... I dont think it matters. Just dont have more than a few affiliate links each page (within the content, not inclduing sidebar, footer etc.).