Confidence Intervals Flashcards
1
Q
What is a confidence interval?
A
It is a range of values in which the population mean is thought to lie.
2
Q
How do you write confidence intervals?
A
U+-ksigma/rootn.
3
Q
What does a P % confidence interval represents?
A
It represents that 90 percent of the time the population mean lies within such intervals.
4
Q
How do you unbias a sample variance?
A
You multiply it by n/n-1 to get the population variance.If the sample size is large.
5
Q
What is the width of the confidence interval related to?
A
A larger sample size leads to a narrower interval,Increasing the population variability or confidence level increases the width.
