ChiSquared hypothesis testing  Hypothesis Testing
ChiSquared hypothesis testing
Lessons
Notes:
If a claim is made about population variance, we can test this claim using our sample variance using a ChiSquared distribution,
• ChiSquared: $X^2=\frac{(n1)s^2}{\sigma ^2}$
$n$: sample size
$s$: sample standard deviation
$\sigma$: population standard deviation
$(n1)$: is also called “degrees of freedom”
• ChiSquare table gives critical value area to the right

1.
Variance Hypothesis Testing
A sample of 10 dumbbells is weighted. The variance of this sample is 25 grams. With a 90% confidence level what can be said about the following claims: