AdSense ad targeting

Trying to figure out targeting, index page vs subpage

[mayor]

I recently put AdSense on a site for the first time. I put the code on the index page and one subpage

Ads displayed on the index page are exceptionally targeted. Ads displayed on the subpage are the same as those on the index page and they are exceptionally un-targeted for that page.

It's clear to me that Google can do an excellent job of targeting ads for the content of the page. So why aren't they serving targeted ads for the subpage?

[danny]

Some fraction of my pages (not always the same pages) always have site-specific ads instead of page-specific ones. Could be a shortage of ads, a glitch with the mediapartners spider, or a deliberate feature.

[europeforvisitors]

Give it time. Others have reported that it can take a while for the MediaPartnerbot to work its way through a site and display targeted ads on inside pages. In my experience, new pages will display targeted ads quickly on sites that have been AdSense partners for a while, assuming that AdSense has identified the topic of each new page and that relevant ads are available.