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+--- Thread: q-----2? - goal13 (/showthread.php?tid=685363)
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q-----2? - goal13 - ArchivalUser - 06-30-2012
A med student gave his USMLE step 1 and found his score is 1.5 SD above the mean.What is his percentile.
0 - ArchivalUser - 06-30-2012
1 SD above mean=84
84+6.7=90.7
90.7
0 - ArchivalUser - 06-30-2012
so whats it
0 - ArchivalUser - 06-30-2012
yes sammi is correct
0 - ArchivalUser - 06-30-2012
i didnt knew the 84 stuff....
0 - ArchivalUser - 06-30-2012
84?
0 - ArchivalUser - 06-30-2012
1..5 SD above the mean means nearly (0.15+2.4+6.75) % of the observations are above this value =9.2 % ....he would be 91.8 percentile
sammi made probably a rough estimate
0 - ArchivalUser - 06-30-2012
for whoever wants to know simply
http://library.thinkquest.org/C0122162/standard_deviation.htm
0 - ArchivalUser - 06-30-2012
@goal13 - can you please explain where you got 0.15, 2.4 and 6.75 from please? i haven't brushed up on my biostats in a while and i cant seem to figure it out...??
0 - ArchivalUser - 06-30-2012
Below the mean=.15%+2.4%+13.5%+34%=50%
same values above the mean
Hence 1.5 SD above the mean=
50+34+13.5/2=90.75%
Or
100-0.15-2.4-13.5/2=90.7%