Why does my index page show irrelevant ads?

Geo-targeting issue?

[HarryM]

I have a seperate channel for my index page. Naturally the index page has links (and therefore keywords) to all site themes. However I keep these keywords to a minimum, and the page is optimised for single keywords and two-word phrases relating to the main site theme. Yet the page often shows adds for other themes, even for keywords that occur only once.

If I set the Preview Tool's Geo-target to Auto, all the ads shown in the Extended Ad List are correctly targeted, and there are many of them. But if I set Geo-target to a specific region I also see other ads more appropriate to other areas of the site. I can understand this as the required ads may not be allowed to be shown in that region. But this even applies when Geo-target is set to my own region (the UK) where I would expect to see the same correctly targeted ads as with Auto. (Unless I am misunderstanding the Auto function.)

What I actually see on my page is sometimes the same as Geo-target=Auto (correct) and sometimes the same as Geo-target=UK (incorrect). If I refresh the page the ads usually swap to the other Geo-target setting.

Anyone know the reason? I may be able to get around this in a practical sense, but I'm trying to understand the mechanism of why this happens.

[Jon_King]

I've had this on and off for about 6 months. As long as you have on-topic copy around the ads I would say it will work itself out.

[HarryM]

Yes, I can probably ged rid of some of the unwanted ads and improve things by reworking the page. But what puzzles me is why 'Auto' and 'UK' Geo-target settings should be different, and why they cycle in and out. (It's a .com site but hosted in the UK.)