We test everything with t-bars in very tightly controlled environments. For arbitrage, that is not as elegant a solution as an A/B or multivariate test.
I measure average Adsense payout per click versus the money I paid for the click. So if I start with the standard 50% CTR template and you pay $0.10 per click in 7search, then you need to make over $0.20 per click in Adsense to break even. This is my first factor.
If Adsense payout is really good, but for some reason CTR is low, I keep the niche, but my script changes the template. If CTR is still low, I'll dump the niche. This is second factor. Some niches are just that you can't get CTR up. Almost all computer related niches are like this, or at least for me. I just can't get good CTR from those.
And how long to test.. I usually test for 50 Adsense clicks. Then you'll see pretty much accurate average Adsense CPC.
Please remember that if you are going to do split testing, the keyword better pay REALLY well because other than that, it's just waste of time.
Yeah, I said I have automated script that changes the template, but I still drop niches if they don't produce enough ROI.Unless you automate your split testing...
For T-bars: Ack Really mathematical...Start here Wiki on T-Testing
Basically it is a graphical way to visualize error ranges on testing. Once a gap opens between the top of one test bar and the bottom of the other, you can usually stop testing the poorer performer. All of the functions are available in excel, so once you understand what it is and what the limitations are, you just need to give the spreadsheet data.
I actually have a script that checks CTR per keyword, but I haven't found the time to write a script that would remove bad keywords from 7search. So at the moment I drop the whole niche. Maybe in the future I'll optimize the script finallyDo you test ctr on each keyword? you can optimize a campaign nicely that way.
How would one test ctr for a specific url? I guess I could extract the keyword from referrer URL, but how would I measure the CTR? Some javascript magic to test if the user clicked an adsense link?
Do you know some good books or online tutorials on using excel for statistical analysis? It's one thing I need to get better at.