I think Hitchcock had a thing about hills: think of the house on the hill in 'Psycho.' Then, in 'Vertigo,' Scottie is forever traversing the city, going downhill all the time as he goes deeper and deeper into himself. It's as if Hitchcock is using San Francisco as a psychological map.
Polanski's 'Chinatown' is a film that I have purposefully and consciously imitated, but 'Vertigo' is one that has got into my bloodstream. Every time I reappraise things that I've done, the influence is there, time and time again.