The charts on this page are great: http://reductionism.net.seanic.net/brucegary3/Speculations/innovations(t).html …pic.twitter.com/iIiE4PT7BJ
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Hal is right, but I lean the other way and wonder if there are other major sources of mismeasurement--IT has brought explosion in new product varieties that skew measurement (& contra Chad this is something new)
Price indices are almost certainly upward biased, there is a shift across the production boundary into home production (opposite of 2nd half of 20th century shift) and GDP measures are not invariant to new business models
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