See what we can offer to your school
"SimpleStudy just makes sense...โ
Get the best plan for your school
10 cards from this deck
xห=โxin\bar{x} = \frac{\sum x_i}{n}xห=nโxiโโ
s2=1nโ1โ(xiโxห)2s^2 = \frac{1}{n-1}\sum(x_i - \bar{x})^2s2=nโ11โโ(xiโโxห)2
Bessel's correction; makes it an unbiased estimator
sn\frac{s}{\sqrt{n}}nโsโ
XหโผN(ฮผ,ฯ2n)\bar{X} \sim N\left(\mu, \frac{\sigma^2}{n}\right)XหโผN(ฮผ,nฯ2โ)
xหยฑzรsn\bar{x} \pm z \times \frac{s}{\sqrt{n}}xหยฑzรnโsโ
1.96
No, only before sampling; after, ฮผ\muฮผ is or isn't in interval
Decreases width (smaller standard error)
Use sss when population variance unknown; ฯ\sigmaฯ when known
Select your subjects, and get access to A+ resources today.