The Importance of Perceived Speed

"Page speed is in the eye of the beholder" - me.

As I was browsing youtube recently, I was struck by just how fast clicking through pages seemed.
Now obviously, Google should have the fastest servers on the planet, but it got me thinking about that red loading bar youtube introduced last year.

Does this loading bar effect the 'perceived' speed of the page? does it seem faster than other design patterns? My guess is yes, but I wanted to test this hypothesis myself.

Below are three design patterns for content loading, in each case the content is loaded at exactly the same speed. See for yourself which one feels fastest.

Top Loading Bar

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Ajax Spinner

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No Loader

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