I was searching on google for anti-wrinkle stuff..and saw this adword ads came up on the side http://www.wrinkle-treatment-guide.com/ and i looked into the site it doesn't sell any products but it does have it's own adsense ads displayed ...so it made me wonder does the owner actually pays adwords to his site so he can make some from adsense...is that worthwhile or is that really pointless?
Whether it is worthwhile would depend on your CTR. I've seen it said on these forums that people who visit a site through adwords is more likely to leave through adsense. You'd need to do your own sums to see if it's worthwhile. You know your CTR, and you'd know your adwords expenditure. So it's pretty simple math.
It depends on more than just your CTR. What you need to know is your average earnings per visitor. If each visitor to your site earns you $0.20 on average, then you can make a great profit spending $0.05 on AdWords to get visitors. If you only make $0.01 for each average visitor, AdWords is going to be a losing proposition.
Here is the empirical formula: If your site's overall effective CPM is > $50.00, start bidding the minimum on AdWords
I'd agree with the thought that people entering from an ad are more likely to leave by an ad. I buy traffic from Google Adwords and Yahoo (Overture) and several tier two providers like 7search and Searchfeed. One thing you can look for is a wide spread of bids on a set of keywords. If top bids is 10 time the 5th bid or bids on related keywords, you can do well by buying for a dime and a dollar. These are people that are searching, they are coming to your site to click on something not coming to stay and chat. Another thing I've noticed is that many of the people that come in through the top ad networks will hit one of my Adsense ads and then hit the back button and visit another Adsense ad. Some do more than two clicks. I'd advise trying it out if you have a site with a good eCPM and use some tracking software to see what these visitors do. Also, append your link from the ad network with something easily interpreted like www.mysite.com?ysm (Yahoo Search Marketing) or www.mysite.com?adwords.
Overall effective CPM is equal to the total revenue generated by your site per 1000 impressions (adsense + affiliate + whatever else) In AdSense, select aggregate data and your AdSense only effective CPM is in the column called 'Page eCPM'
You would have to bid on keywords cheaper than the ones displayed on your site. If you are bidding on keywords that are the same as what you show on your site you will lose money. If you bid on other keywords that are cheaper and not as targetted to your content the CTR will be lower on your site than your CTR from your ads and again, you will lose money. It can be done but it isn't easy.
i tested it on one of my sites. my ad gets virtually no impressions and therefore clicks for the price that i am willing to pay per click (around $.15). because of this i am not feeding adsense revenue at all.