[quote author=hammer88 link=topic=7684.msg526'5#msg526'5 date=1251784'75]
i'm leaning towards clee's approach.
but erro... please specify where you might put some of those words like rehearsal, or running, brushing teeth, or pregnant. do you just have 5 top categories and a flat level of many keywords under that?
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I'm still working on my hierarchy, and so far only have the "who" top-level for peoples names. My idea is to use a "what" top-level to include keywords to describe important things in the image, such as boat, sea, flower, mountain... nouns mostly. Then also have a top-level for "why" to describe why the image was taken (what is happening in the image), such as your examples of rehersal, running, brushing... verbs mostly. Quite possible I will also use sub-levels within the catagories. Maybe also a top-level for "genre" where I can mark images as nature, streetphoto, art, architecture etc.
Another use of the top-levels is that they serve as an indication on wheter I've judged this image regarding "what" or "who" for instance. If I don't have the "who" top-level, how will I know what images I have left to tag for people? For this purpose I also have a "no-one" keyword within the "who" category, for the images where there are no people. This makes it easy to create a smart collection where "keywords doesn't contain who" to automatically see all images not tagged for people.