Has it all really come to this - > From: Kevin Marks <[EMAIL PROTECTED]> > This is completely statistically illiterate. > > Firstly, the average of a 1-5 rating is 1+2+3+4+5/5 = 3, NOT 3.5. For > it to be 2.5 you'd need to use a zero to five scale. > > Your sample is 35 of 500, so expressing averages to 11 decimal places > is not techie, it's foolish. Assuming a normal ditribution, the > standard estimate of error is 1/sqrt(n) = about 17%. So your mean is > 3.25 +/- 0.5. > > (You could calculate a proper standard deviation from your data and > quote that; the point is that the difference between 3.25 and 3 is > well within the margin of error) > > > Your bins are not the same size (1-2 has 3 datapoints on, the others > have 2.) In any case, binning on an arbitrary scale is not really > helpful. You'd be better off giving quintiles (rank the scores in > order, break them into even-sized numbers of users, and report the > means of those). ============SPONSORED BY REALNETWORKS================ New RealSystem iQ - Bringing Intelligence to Internet Media Delivery Featuring the breakthrough quality of RealAudio 8 & RealVideo 8 ====> To learn more please visit: http://www.realnetworks.com/iq --- To register for Streaming Media Asia/Berlin/West/Europe/East 2001: http://www.streamingmedia.com/upcoming.asp --- You are currently subscribed to skunkworks To unsubscribe send a blank email to [EMAIL PROTECTED] To switch to digest mode, send email to: [EMAIL PROTECTED]
