UNIT5 Confidence Intervals Flashcards
1
Q
Are population meand and sample mean the same thing?
A
No
2
Q
What is the confiedence interval for the mean?
A
Rnage of value within which the population means U lies with a certain probability
3
Q
What is a confidence limit?
A
Upper and lower limits of the interval
4
Q
What is the normal confidence level in chemistry?
A
95%
5
Q
As you increase the number of samples, what happens to uncertainty and distribution?
A
Reduction of uncertainty and distribution
6
Q
__ CI in more precise
A
Smaller
7
Q
What is the significance level of the confidence interval is 95%?
A
5%
8
Q
When do you use t and z test?
A
t- small sample <20
z- large sample >20
9
Q
What do you use to calculate an outlier?
A
Qtest
10
Q
When can you reject an outlier?
A
Q>Qcrit
11
Q
If there is retention with the Q test, what is the better center to use?
A
Median
