Question

News stories reporting poll results often include the statement "results for subgroups have a larger margin of error." This is because O people in the subgroups probably lie. O people in the subgroups may not understand the question, O subgroups have a smaller sample size. O as usual; news reports are wrong.

Answer 1

Sol:

as sample size increases ,margin of error decreaes.

use confidence .t to get the margin of error in excel

case:

n=10

sd=10

alpha=0.05

moe1=CONFIDENCE.T(0.05;10;10)=7.15356906

case2"

n=100

sd=10

alpha=0.05

moe2==CONFIDENCE.T(0.05;10;100)=1.984216952

margin of error reduced from 7.15 to 1.98 when sample size increased from 10 to 100.

MARK ANSWER:

subgroups have a smaller sample size.

OPTION C