rba@allegra.UUCP (10/25/83)
The original citation for the magic number was: George A. Miller, The magical number seven, plus or minus two: Some limits on our capacity for processing information. Psychological Review, 1956, 63, 81-97. This was updated a few years ago by Donald Broadbent, in an article which asserted that the processing limit was closer to five: D.E. Broadbent. The magical number seven after fifteen years. In A. Kennedy and A. Wilkes (Eds.) Studies in long term memory. Wiley: NY, 1975, 3-18. However, while most psychologists believe that there is some limit to short-term memory, almost no serious researcher now takes either of the magic numbers literally. (Although there have been many jokes about the decline in intelligence -- because the magic number dropped from 7 to 5. And, there have been other jokes about continuing the series of magic numbers 7,5,3,1,-1...) Indeed a colleague of mine (Steve Hanson) told me he talked to George Miller (Steve teaches statistics at Princeton where Miller is a professor) and not even Miller accepts the 7+-2 model any more. In any case, as has been pointed out, even if there were a magic number for STM it isn't clear how that should be related to the number of items on a distribution list. Bob Allen, allegra!rba, BTL-CSO
israel@umcp-cs.UUCP (10/26/83)
I don't think that any length list of distribution levels will go over
the 5+-2 limit because I think the relative need is for two items.
Even if the list is very long, people will read along it and remember
the currently best choice. All they have to consider is the current
choice and the so-far best choice.
--
^-^ Bruce ^-^
University of Maryland, Computer Science
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