Posted by
Michelle Tan on
Jun 17, 2011; 8:02am
URL: http://spssx-discussion.165.s1.nabble.com/Margin-of-error-tp4481843p4498021.html
Thanks a lot!
I calculate MOE based on this formula: 1.645*â (padj *(1-padj)/
(n+1.645^2)) using adjusted Waldâs method where padj = (x+ zα/2 ^2/2)/(n+
zα/2 ^2);
My total population should be 1300 instead of 3100. Apologise for the
error. As some cases may be falls under more than one category based on the
criteria set, total pop = 1300 and not the sum of 1000+500+71
Since my population size is known, does it make sense to adjust the MOE
using finite population corrector as per below?
MOE after using FPC = 1.645*â (padj *(1-padj)/ (n+1.645^2)) *sqrt((N-n)/(N-
1))
Will there be issue of over adjustment if i use above?
If not, how else can I take population size into account when calculating
MOE?
It just doesnât make sense to tell people that regardless of size of my
total population, as long as my sample size is small, my margin of error is
high
e.g in my case,
for N3, I am sampling 94% (67/71) of the total population (but margin of
error is 5.45%) compared to N1 where Proportion of sampled cases in N1
=221/1000 but margin of error is 1.52%
=====================
To manage your subscription to SPSSX-L, send a message to
[hidden email] (not to SPSSX-L), with no body text except the
command. To leave the list, send the command
SIGNOFF SPSSX-L
For a list of commands to manage subscriptions, send the command
INFO REFCARD