Will adding another ad network reduce Adsense RPM/CTR?

I just added Lijit and I'm seeing a drop in CTR.

[littlecubpanda]

So all of my Adsense ads are toward the TOP of my page, while I put some Lijit ads on the bottom.

I've noticed a drop in CTR for my Adsense ads, especially on the main page where the Lijit ads are getting a fill rate of about 50%.

Now, Lijit only makes pennies a day. It's not much. Now I'm wondering if it's worth it at all.

I just don't see how it would effect Adsense, since the ads are so far apart on the page, people who visit the page see all the Adsense ads FIRST -- but something isn't right.

[ember]

You would think that doubling the number of ads on a page would double the revenue, but it does not work that way. The more ads, the more they start to cannibalize each other. You're losing some adsense clicks, which pay more, to the other network, which pays less. If it is way less, you will start to see an overall revenue drop.

[littlecubpanda]

2,800 impressions through lijit today = $1.58 lol

I'm just going to put it on my non-Adsense sites.

[littlecubpanda]

I'm surprised by the quality of ads Lijit shows -- excellent ads -- but either nobody is clicking on them or they just pay per thousand impressions. I'm not sure how it works or what it is. They just pay awful, though!

[matbennett]

Have you thought about serving them together through DFP? That way you can avoid unfilled inventory and actually use the second network to drive up the price of AdSense?

[littlecubpanda]

I just loaded up DFP for the first time -- any tips? Can you give me an idea of why this would work with Adsense and Lijit put together? How it works?

Adsense serves ads 100% of the time, according to the performance data (except on one site that has some "bad words" on it, where the fill rate is 33%).

[matbennett]

DFP is a pretty big topic. As a general approach though, adding other networks in as price priority items can force AdSense to up its bid to beat them.

Set the price priority to around the CPM that you receive (including passback) and just keep updating that figure as it changes.

except on one site that has some "bad words" on it, where the fill rate is 33%)

That generally just shows up that the publisher doesn't agree to what they have signed up for. Most networks are not 100% fill. Managing fill rates is an art in itself.

The other mistake people make is to then just set the other network to have "first bite" of the impression and backfill to adsense. That can result in lower Adsense performance, as adsense doesn't check a chance to compete on a level playing field.

[ember]

DFP's learning curve is steep. You really need to research how it works with Adsense. Matbennett is right that it can increase adsense revenue, but it depends on which networks compete with adsense in the same slots. DFP also lets you show 4 adsense units on a page if you want. That, too, has to be done correctly (and I don't do it since, again, cannibalization starts to factor in).