US Patent 7895293 Web page experiments with fragmented section variations

In one general aspect, a page identifier of a test page having code defining a content section, the content section comprising a plurality of content section fragments, is received. A content item group is selected from a collection of content item groups, each content item group defining an association of content items with content section fragments of the content section. Each identified content item in the selected content item group is transmitted for placement on the test page in the associated content section fragment.